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Matthieu Schaller authoredMatthieu Schaller authored
engine.c 75.02 KiB
/*******************************************************************************
* This file is part of SWIFT.
* Copyright (c) 2012 Pedro Gonnet (pedro.gonnet@durham.ac.uk)
* 2015 Peter W. Draper (p.w.draper@durham.ac.uk)
*
* This program is free software: you can redistribute it and/or modify
* it under the terms of the GNU Lesser General Public License as published
* by the Free Software Foundation, either version 3 of the License, or
* (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public License
* along with this program. If not, see <http://www.gnu.org/licenses/>.
*
******************************************************************************/
/* Config parameters. */
#include "../config.h"
/* Some standard headers. */
#include <float.h>
#include <limits.h>
#include <sched.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>
#include <stdbool.h>
/* MPI headers. */
#ifdef WITH_MPI
#include <mpi.h>
#endif
#ifdef HAVE_LIBNUMA
#include <numa.h>
#endif
/* This object's header. */
#include "engine.h"
/* Local headers. */
#include "atomic.h"
#include "cell.h"
#include "clocks.h"
#include "cycle.h"
#include "debug.h"
#include "error.h"
#include "hydro.h"
#include "minmax.h"
#include "part.h"
#include "partition.h"
#include "timers.h"
#define engine_redistribute_alloc_margin 1.2
const char *engine_policy_names[12] = {
"none", "rand", "steal", "keep",
"block", "fix_dt", "cpu_tight", "mpi",
"numa_affinity", "hydro", "self_gravity", "external_gravity"};
/** The rank of the engine as a global variable (for messages). */
int engine_rank;
/**
* @brief Link a density/force task to a cell. *
* @param e The #engine.
* @param l The #link.
* @param t The #task.
*
* @return The new #link pointer.
*/
struct link *engine_addlink(struct engine *e, struct link *l, struct task *t) {
const int ind = atomic_inc(&e->nr_links);
if (ind >= e->size_links) {
error("Link table overflow.");
}
struct link *res = &e->links[ind];
res->next = l;
res->t = t;
return res;
}
/**
* @brief Generate the ghosts all the O(Npart) tasks for a hierarchy of cells.
*
* Tasks are only created here. The dependencies will be added later on.
*
* @param e The #engine.
* @param c The #cell.
* @param super The super #cell.
*/
void engine_make_ghost_tasks(struct engine *e, struct cell *c,
struct cell *super) {
struct scheduler *s = &e->sched;
/* Am I the super-cell? */
if (super == NULL && c->nr_tasks > 0) {
/* Remember me. */
super = c;
/* Local tasks only... */
if (c->nodeID == e->nodeID) {
/* Generate the ghost task. */
c->ghost = scheduler_addtask(s, task_type_ghost, task_subtype_none, 0, 0,
c, NULL, 0);
/* Add the drift task. */
c->drift = scheduler_addtask(s, task_type_drift, task_subtype_none, 0, 0,
c, NULL, 0);
/* Add the init task. */
c->init = scheduler_addtask(s, task_type_init, task_subtype_none, 0, 0, c,
NULL, 0);
/* Add the kick task. */
c->kick = scheduler_addtask(s, task_type_kick, task_subtype_none, 0, 0, c,
NULL, 0);
}
}
/* Set the super-cell. */
c->super = super;
/* Recurse. */
if (c->split)
for (int k = 0; k < 8; k++)
if (c->progeny[k] != NULL)
engine_make_ghost_tasks(e, c->progeny[k], super);
}
/** * @brief Redistribute the particles amongst the nodes according
* to their cell's node IDs.
*
* The strategy here is as follows:
* 1) Each node counts the number of particles it has to send to each other
* node.
* 2) The number of particles of each type is then exchanged.
* 3) The particles to send are placed in a temporary buffer in which the
* part-gpart links are preserved.
* 4) Each node allocates enough space for the new particles.
* 5) (Asynchronous) communications are issued to transfer the data.
*
*
* @param e The #engine.
*/
void engine_redistribute(struct engine *e) {
#ifdef WITH_MPI
const int nr_nodes = e->nr_nodes;
const int nodeID = e->nodeID;
struct space *s = e->s;
struct cell *cells = s->cells;
const int nr_cells = s->nr_cells;
const int *cdim = s->cdim;
const double ih[3] = {s->ih[0], s->ih[1], s->ih[2]};
const double dim[3] = {s->dim[0], s->dim[1], s->dim[2]};
struct part *parts = s->parts;
struct xpart *xparts = s->xparts;
struct gpart *gparts = s->gparts;
ticks tic = getticks();
/* Allocate temporary arrays to store the counts of particles to be sent
and the destination of each particle */
int *counts, *g_counts;
if ((counts = (int *)malloc(sizeof(int) *nr_nodes *nr_nodes)) == NULL)
error("Failed to allocate count temporary buffer.");
if ((g_counts = (int *)malloc(sizeof(int) *nr_nodes *nr_nodes)) == NULL)
error("Failed to allocate gcount temporary buffer.");
bzero(counts, sizeof(int) * nr_nodes * nr_nodes);
bzero(g_counts, sizeof(int) * nr_nodes * nr_nodes);
// MATTHIEU: Should be int and not size_t once Pedro's changes are merged.
size_t *dest, *g_dest;
if((dest = (size_t *)malloc(sizeof(size_t) * s->nr_parts)) == NULL)
error("Failed to allocate dest temporary buffer.");
if((g_dest = (size_t *)malloc(sizeof(size_t) * s->nr_gparts)) == NULL)
error("Failed to allocate g_dest temporary buffer.");
/* The counts array is indexed as count[from * nr_nodes + to]. */
for (size_t k = 0; k < s->nr_parts; k++) {
/* Periodic boundary conditions */
for (int j = 0; j < 3; j++) {
if (parts[k].x[j] < 0.0)
parts[k].x[j] += dim[j];
else if (parts[k].x[j] >= dim[j])
parts[k].x[j] -= dim[j];
}
const int cid = cell_getid(cdim, parts[k].x[0] * ih[0],
parts[k].x[1] * ih[1], parts[k].x[2] * ih[2]);
/* if (cid < 0 || cid >= s->nr_cells)
error("Bad cell id %i for part %i at [%.3e,%.3e,%.3e].",
cid, k, parts[k].x[0], parts[k].x[1], parts[k].x[2]); */
dest[k] = cells[cid].nodeID;
counts[nodeID * nr_nodes + dest[k]] += 1;
}
/* Sort the particles according to their cell index. */ space_parts_sort(s, dest, s->nr_parts, 0, nr_nodes - 1, e->verbose);
/* Now, do the same for the gparts */
for (size_t k = 0; k < s->nr_gparts; k++) {
/* Periodic boundary conditions */
for (int j = 0; j < 3; j++) {
if (gparts[k].x[j] < 0.0)
gparts[k].x[j] += dim[j];
else if (gparts[k].x[j] >= dim[j])
gparts[k].x[j] -= dim[j];
}
const int cid = cell_getid(cdim, gparts[k].x[0] * ih[0],
gparts[k].x[1] * ih[1], gparts[k].x[2] * ih[2]);
/* if (cid < 0 || cid >= s->nr_cells)
error("Bad cell id %i for part %i at [%.3e,%.3e,%.3e].",
cid, k, g_parts[k].x[0], g_parts[k].x[1], g_parts[k].x[2]); */
g_dest[k] = cells[cid].nodeID;
g_counts[nodeID * nr_nodes + dest[k]] += 1;
}
/* Sort the gparticles according to their cell index. */
space_gparts_sort(gparts, g_dest, s->nr_gparts, 0, nr_nodes - 1);
/* Get all the counts from all the nodes. */
if (MPI_Allreduce(MPI_IN_PLACE, counts, nr_nodes * nr_nodes, MPI_INT, MPI_SUM,
MPI_COMM_WORLD) != MPI_SUCCESS)
error("Failed to allreduce particle transfer counts.");
/* Get all the g_counts from all the nodes. */
if (MPI_Allreduce(MPI_IN_PLACE, g_counts, nr_nodes * nr_nodes, MPI_INT,
MPI_SUM, MPI_COMM_WORLD) != MPI_SUCCESS)
error("Failed to allreduce gparticle transfer counts.");
/* Each node knows how many parts and gparts will be transferred to every
other node. We can start preparing to receive data */
/* Get the new number of parts and gparts for this node */
size_t nr_parts = 0, nr_gparts = 0;
for (int k = 0; k < nr_nodes; k++) nr_parts += counts[k * nr_nodes + nodeID];
for (int k = 0; k < nr_nodes; k++)
nr_gparts += g_counts[k * nr_nodes + nodeID];
/* Allocate the new arrays with some extra margin */
struct part *parts_new = NULL;
struct xpart *xparts_new = NULL;
struct gpart *gparts_new = NULL;
if (posix_memalign((void **)&parts_new, part_align,
sizeof(struct part) * nr_parts *
engine_redistribute_alloc_margin) != 0)
error("Failed to allocate new part data.");
if (posix_memalign((void **)&xparts_new, xpart_align,
sizeof(struct xpart) * nr_parts *
engine_redistribute_alloc_margin) != 0)
error("Failed to allocate new xpart data.");
if (posix_memalign((void **)&gparts_new, gpart_align,
sizeof(struct gpart) * nr_gparts *
engine_redistribute_alloc_margin) != 0)
error("Failed to allocate new gpart data.");
/* Prepare MPI requests for the asynchronous communications */
MPI_Request *reqs;
if ((reqs = (MPI_Request *)malloc(sizeof(MPI_Request) * 6 * nr_nodes)) ==
NULL)
error("Failed to allocate MPI request list.");
for (int k = 0; k < 6 * nr_nodes; k++) reqs[k] = MPI_REQUEST_NULL;
/* Emit the sends and recvs for the particle and gparticle data. */
size_t offset_send = 0, offset_recv = 0;
size_t g_offset_send = 0, g_offset_recv = 0; for (int k = 0; k < nr_nodes; k++) {
/* Indices in the count arrays of the node of interest */
const int ind_send = nodeID * nr_nodes + k;
const int ind_recv = k * nr_nodes + nodeID;
/* Are we sending any part/xpart ? */
if (counts[ind_send] > 0) {
/* If the send is to the same node, just copy */
if (k == nodeID) {
memcpy(&parts_new[offset_recv], &s->parts[offset_send],
sizeof(struct part) * counts[ind_recv]);
memcpy(&xparts_new[offset_recv], &s->xparts[offset_send],
sizeof(struct xpart) * counts[ind_recv]);
offset_send += counts[ind_send];
offset_recv += counts[ind_recv];
/* Else, emit some communications */
} else {
if (MPI_Isend(&s->parts[offset_send], counts[ind_send],
e->part_mpi_type, k, 3 * ind_send + 0, MPI_COMM_WORLD,
&reqs[6 * k]) != MPI_SUCCESS)
error("Failed to isend parts to node %i.", k);
if (MPI_Isend(&s->xparts[offset_send], counts[ind_send],
e->xpart_mpi_type, k, 3 * ind_send + 1, MPI_COMM_WORLD,
&reqs[6 * k + 1]) != MPI_SUCCESS)
error("Failed to isend xparts to node %i.", k);
offset_send += counts[ind_send];
}
}
/* Are we sending any gpart ? */
if (g_counts[ind_send] > 0) {
/* If the send is to the same node, just copy */
if (k == nodeID) {
memcpy(&gparts_new[g_offset_recv], &s->gparts[offset_send],
sizeof(struct gpart) * g_counts[ind_recv]);
g_offset_send += g_counts[ind_send];
g_offset_recv += g_counts[ind_recv];
/* Else, emit some communications */
} else {
if (MPI_Isend(&s->gparts[g_offset_send], g_counts[ind_send],
e->gpart_mpi_type, k, 3 * ind_send + 2, MPI_COMM_WORLD,
&reqs[6 * k + 2]) != MPI_SUCCESS)
error("Failed to isend gparts to node %i.", k);
g_offset_send += counts[ind_send];
}
}
/* Now emit the corresponding Irecv() */
/* Are we receiving any part/xpart from this node ? */
if (k != nodeID && counts[ind_recv] > 0) {
if (MPI_Irecv(&parts_new[offset_recv], counts[ind_recv], e->part_mpi_type,
k, 3 * ind_recv + 0, MPI_COMM_WORLD,
&reqs[6 * k + 3]) != MPI_SUCCESS)
error("Failed to emit irecv of parts from node %i.", k);
if (MPI_Irecv(&xparts_new[offset_recv], counts[ind_recv],
e->xpart_mpi_type, k, 3 * ind_recv + 1, MPI_COMM_WORLD,
&reqs[6 * k + 4]) != MPI_SUCCESS)
error("Failed to emit irecv of xparts from node %i.", k);
offset_recv += counts[ind_recv];
}
/* Are we receiving any gpart from this node ? */
if (k != nodeID && g_counts[ind_recv] > 0) {
if (MPI_Irecv(&gparts_new[g_offset_recv], g_counts[ind_recv], e->gpart_mpi_type, k, 3 * ind_recv + 2, MPI_COMM_WORLD,
&reqs[6 * k + 5]) != MPI_SUCCESS)
error("Failed to emit irecv of gparts from node %i.", k);
g_offset_recv += g_counts[ind_recv];
}
}
/* Wait for all the sends and recvs to tumble in. */
MPI_Status stats[6 * nr_nodes];
int res;
if ((res = MPI_Waitall(6 * nr_nodes, reqs, stats)) != MPI_SUCCESS) {
for (int k = 0; k < 6 * nr_nodes; k++) {
char buff[MPI_MAX_ERROR_STRING];
int res;
MPI_Error_string(stats[k].MPI_ERROR, buff, &res);
message("request %i has error '%s'.", k, buff);
}
error("Failed during waitall for part data.");
}
/* Verify that all parts are in the right place. */
/* for ( k = 0 ; k < nr_parts ; k++ ) {
cid = cell_getid( cdim , parts_new[k].x[0]*ih[0] , parts_new[k].x[1]*ih[1]
, parts_new[k].x[2]*ih[2] );
if ( cells[ cid ].nodeID != nodeID )
error( "Received particle (%i) that does not belong here (nodeID=%i)."
, k , cells[ cid ].nodeID );
} */
/* Set the new part data, free the old. */
free(parts);
free(xparts);
free(gparts);
s->parts = parts_new;
s->xparts = xparts_new;
s->gparts = gparts_new;
s->nr_parts = nr_parts;
s->nr_gparts = nr_gparts;
s->size_parts = engine_redistribute_alloc_margin * nr_parts;
s->size_gparts = engine_redistribute_alloc_margin * nr_gparts;
/* Clean up the temporary stuff. */
free(reqs);
free(counts);
free(dest);
/* Be verbose about what just happened. */
if (e->verbose) {
int my_cells = 0;
for (int k = 0; k < nr_cells; k++)
if (cells[k].nodeID == nodeID) my_cells += 1;
message("node %i now has %zi parts in %i cells.", nodeID, nr_parts,
my_cells);
}
if (e->verbose)
message("took %.3f %s.", clocks_from_ticks(getticks() - tic),
clocks_getunit());
#else
error("SWIFT was not compiled with MPI support.");
#endif
}
/**
* @brief Repartition the cells amongst the nodes.
*
* @param e The #engine.
*/
void engine_repartition(struct engine *e) {
#if defined(WITH_MPI) && defined(HAVE_METIS)
ticks tic = getticks();
/* Clear the repartition flag. */
enum repartition_type reparttype = e->forcerepart;
e->forcerepart = REPART_NONE;
/* Nothing to do if only using a single node. Also avoids METIS
* bug that doesn't handle this case well. */
if (e->nr_nodes == 1) return;
/* Do the repartitioning. */
partition_repartition(reparttype, e->nodeID, e->nr_nodes, e->s,
e->sched.tasks, e->sched.nr_tasks);
/* Now comes the tricky part: Exchange particles between all nodes.
This is done in two steps, first allreducing a matrix of
how many particles go from where to where, then re-allocating
the parts array, and emitting the sends and receives.
Finally, the space, tasks, and proxies need to be rebuilt. */
/* Redistribute the particles between the nodes. */
engine_redistribute(e);
/* Make the proxies. */
engine_makeproxies(e);
/* Tell the engine it should re-build whenever possible */
e->forcerebuild = 1;
if (e->verbose)
message("took %.3f %s.", clocks_from_ticks(getticks() - tic),
clocks_getunit());
#else
error("SWIFT was not compiled with MPI and METIS support.");
#endif
}
/**
* @brief Add up/down gravity tasks to a cell hierarchy.
*
* @param e The #engine.
* @param c The #cell
* @param up The upward gravity #task.
* @param down The downward gravity #task.
*/
void engine_addtasks_grav(struct engine *e, struct cell *c, struct task *up,
struct task *down) {
/* Link the tasks to this cell. */
c->grav_up = up;
c->grav_down = down;
/* Recurse? */
if (c->split)
for (int k = 0; k < 8; k++)
if (c->progeny[k] != NULL)
engine_addtasks_grav(e, c->progeny[k], up, down);
}
/**
* @brief Add send tasks to a hierarchy of cells.
*
* @param e The #engine.
* @param ci The sending #cell.
* @param cj The receiving #cell
*/
void engine_addtasks_send(struct engine *e, struct cell *ci, struct cell *cj) {
#ifdef WITH_MPI
struct link *l = NULL;
struct scheduler *s = &e->sched;
/* Check if any of the density tasks are for the target node. */
for (l = ci->density; l != NULL; l = l->next)
if (l->t->ci->nodeID == cj->nodeID ||
(l->t->cj != NULL && l->t->cj->nodeID == cj->nodeID))
break;
/* If so, attach send tasks. */
if (l != NULL) {
/* Create the tasks. */
struct task *t_xv = scheduler_addtask(s, task_type_send, task_subtype_none,
2 * ci->tag, 0, ci, cj, 0);
struct task *t_rho = scheduler_addtask(s, task_type_send, task_subtype_none,
2 * ci->tag + 1, 0, ci, cj, 0);
/* The send_rho task depends on the cell's ghost task. */
scheduler_addunlock(s, ci->super->ghost, t_rho);
/* The send_rho task should unlock the super-cell's kick task. */
scheduler_addunlock(s, t_rho, ci->super->kick);
/* The send_xv task should unlock the super-cell's ghost task. */
scheduler_addunlock(s, t_xv, ci->super->ghost);
}
/* Recurse? */
else if (ci->split)
for (int k = 0; k < 8; k++)
if (ci->progeny[k] != NULL) engine_addtasks_send(e, ci->progeny[k], cj);
#else
error("SWIFT was not compiled with MPI support.");
#endif
}
/**
* @brief Add recv tasks to a hierarchy of cells.
*
* @param e The #engine.
* @param c The #cell.
* @param t_xv The recv_xv #task, if it has already been created.
* @param t_rho The recv_rho #task, if it has already been created.
*/
void engine_addtasks_recv(struct engine *e, struct cell *c, struct task *t_xv,
struct task *t_rho) {
#ifdef WITH_MPI
struct scheduler *s = &e->sched;
/* Do we need to construct a recv task? */
if (t_xv == NULL && c->nr_density > 0) {
/* Create the tasks. */
t_xv = c->recv_xv = scheduler_addtask(s, task_type_recv, task_subtype_none,
2 * c->tag, 0, c, NULL, 0);
t_rho = c->recv_rho = scheduler_addtask(
s, task_type_recv, task_subtype_none, 2 * c->tag + 1, 0, c, NULL, 0);
}
/* Add dependencies. */
for (struct link *l = c->density; l != NULL; l = l->next) { scheduler_addunlock(s, t_xv, l->t);
scheduler_addunlock(s, l->t, t_rho);
}
for (struct link *l = c->force; l != NULL; l = l->next)
scheduler_addunlock(s, t_rho, l->t);
if (c->sorts != NULL) scheduler_addunlock(s, t_xv, c->sorts);
/* Recurse? */
if (c->split)
for (int k = 0; k < 8; k++)
if (c->progeny[k] != NULL)
engine_addtasks_recv(e, c->progeny[k], t_xv, t_rho);
#else
error("SWIFT was not compiled with MPI support.");
#endif
}
/**
* @brief Exchange cell structures with other nodes.
*
* @param e The #engine.
*/
void engine_exchange_cells(struct engine *e) {
#ifdef WITH_MPI
struct space *s = e->s;
struct cell *cells = s->cells;
const int nr_cells = s->nr_cells;
const int nr_proxies = e->nr_proxies;
int offset[nr_cells];
MPI_Request reqs_in[engine_maxproxies];
MPI_Request reqs_out[engine_maxproxies];
MPI_Status status;
ticks tic = getticks();
/* Run through the cells and get the size of the ones that will be sent off.
*/
int count_out = 0;
for (int k = 0; k < nr_cells; k++) {
offset[k] = count_out;
if (cells[k].sendto)
count_out += (cells[k].pcell_size = cell_getsize(&cells[k]));
}
/* Allocate the pcells. */
struct pcell *pcells;
if ((pcells = (struct pcell *)malloc(sizeof(struct pcell) * count_out)) ==
NULL)
error("Failed to allocate pcell buffer.");
/* Pack the cells. */
cell_next_tag = 0;
for (int k = 0; k < nr_cells; k++)
if (cells[k].sendto) {
cell_pack(&cells[k], &pcells[offset[k]]);
cells[k].pcell = &pcells[offset[k]];
}
/* Launch the proxies. */
for (int k = 0; k < nr_proxies; k++) {
proxy_cells_exch1(&e->proxies[k]);
reqs_in[k] = e->proxies[k].req_cells_count_in;
reqs_out[k] = e->proxies[k].req_cells_count_out;
}
/* Wait for each count to come in and start the recv. */
for (int k = 0; k < nr_proxies; k++) { int pid;
if (MPI_Waitany(nr_proxies, reqs_in, &pid, &status) != MPI_SUCCESS ||
pid == MPI_UNDEFINED)
error("MPI_Waitany failed.");
// message( "request from proxy %i has arrived." , pid );
proxy_cells_exch2(&e->proxies[pid]);
}
/* Wait for all the sends to have finished too. */
if (MPI_Waitall(nr_proxies, reqs_out, MPI_STATUSES_IGNORE) != MPI_SUCCESS)
error("MPI_Waitall on sends failed.");
/* Set the requests for the cells. */
for (int k = 0; k < nr_proxies; k++) {
reqs_in[k] = e->proxies[k].req_cells_in;
reqs_out[k] = e->proxies[k].req_cells_out;
}
/* Wait for each pcell array to come in from the proxies. */
for (int k = 0; k < nr_proxies; k++) {
int pid;
if (MPI_Waitany(nr_proxies, reqs_in, &pid, &status) != MPI_SUCCESS ||
pid == MPI_UNDEFINED)
error("MPI_Waitany failed.");
// message( "cell data from proxy %i has arrived." , pid );
for (int count = 0, j = 0; j < e->proxies[pid].nr_cells_in; j++)
count += cell_unpack(&e->proxies[pid].pcells_in[count],
e->proxies[pid].cells_in[j], e->s);
}
/* Wait for all the sends to have finished too. */
if (MPI_Waitall(nr_proxies, reqs_out, MPI_STATUSES_IGNORE) != MPI_SUCCESS)
error("MPI_Waitall on sends failed.");
/* Count the number of particles we need to import and re-allocate
the buffer if needed. */
int count_in = 0;
for (int k = 0; k < nr_proxies; k++)
for (int j = 0; j < e->proxies[k].nr_cells_in; j++)
count_in += e->proxies[k].cells_in[j]->count;
if (count_in > s->size_parts_foreign) {
if (s->parts_foreign != NULL) free(s->parts_foreign);
s->size_parts_foreign = 1.1 * count_in;
if (posix_memalign((void **)&s->parts_foreign, part_align,
sizeof(struct part) * s->size_parts_foreign) != 0)
error("Failed to allocate foreign part data.");
}
/* Unpack the cells and link to the particle data. */
struct part *parts = s->parts_foreign;
for (int k = 0; k < nr_proxies; k++) {
for (int j = 0; j < e->proxies[k].nr_cells_in; j++) {
cell_link(e->proxies[k].cells_in[j], parts);
parts = &parts[e->proxies[k].cells_in[j]->count];
}
}
s->nr_parts_foreign = parts - s->parts_foreign;
/* Is the parts buffer large enough? */
if (s->nr_parts_foreign > s->size_parts_foreign)
error("Foreign parts buffer too small.");
/* Free the pcell buffer. */
free(pcells);
if (e->verbose)
message("took %.3f %s.", clocks_from_ticks(getticks() - tic),
clocks_getunit());
#else error("SWIFT was not compiled with MPI support.");
#endif
}
/**
* @brief Exchange straying parts with other nodes.
*
* @param e The #engine.
* @param offset The index in the parts array as of which the foreign parts
*reside.
* @param ind The ID of the foreign #cell.
* @param N The number of stray parts.
*
* @return The number of arrived parts copied to parts and xparts.
*/
int engine_exchange_strays(struct engine *e, int offset, size_t *ind,
size_t N) {
#ifdef WITH_MPI
struct space *s = e->s;
ticks tic = getticks();
/* Re-set the proxies. */
for (int k = 0; k < e->nr_proxies; k++) e->proxies[k].nr_parts_out = 0;
/* Put the parts into the corresponding proxies. */
for (size_t k = 0; k < N; k++) {
const int node_id = e->s->cells[ind[k]].nodeID;
if (node_id < 0 || node_id >= e->nr_nodes)
error("Bad node ID %i.", node_id);
const int pid = e->proxy_ind[node_id];
if (pid < 0)
error(
"Do not have a proxy for the requested nodeID %i for part with "
"id=%llu, x=[%e,%e,%e].",
node_id, s->parts[offset + k].id, s->parts[offset + k].x[0],
s->parts[offset + k].x[1], s->parts[offset + k].x[2]);
proxy_parts_load(&e->proxies[pid], &s->parts[offset + k],
&s->xparts[offset + k], 1);
}
/* Launch the proxies. */
MPI_Request reqs_in[2 * engine_maxproxies];
MPI_Request reqs_out[2 * engine_maxproxies];
for (int k = 0; k < e->nr_proxies; k++) {
proxy_parts_exch1(&e->proxies[k]);
reqs_in[k] = e->proxies[k].req_parts_count_in;
reqs_out[k] = e->proxies[k].req_parts_count_out;
}
/* Wait for each count to come in and start the recv. */
for (int k = 0; k < e->nr_proxies; k++) {
int pid;
if (MPI_Waitany(e->nr_proxies, reqs_in, &pid, MPI_STATUS_IGNORE) !=
MPI_SUCCESS ||
pid == MPI_UNDEFINED)
error("MPI_Waitany failed.");
// message( "request from proxy %i has arrived." , pid );
proxy_parts_exch2(&e->proxies[pid]);
}
/* Wait for all the sends to have finished too. */
if (MPI_Waitall(e->nr_proxies, reqs_out, MPI_STATUSES_IGNORE) != MPI_SUCCESS)
error("MPI_Waitall on sends failed.");
/* Count the total number of incoming particles and make sure we have
enough space to accommodate them. */
size_t count_in = 0; for (int k = 0; k < e->nr_proxies; k++) count_in += e->proxies[k].nr_parts_in;
if (e->verbose) message("sent out %zi particles, got %zi back.", N, count_in);
if (offset + count_in > s->size_parts) {
s->size_parts = (offset + count_in) * 1.05;
struct part *parts_new = NULL;
struct xpart *xparts_new = NULL;
if (posix_memalign((void **)&parts_new, part_align,
sizeof(struct part) * s->size_parts) != 0 ||
posix_memalign((void **)&xparts_new, part_align,
sizeof(struct xpart) * s->size_parts) != 0)
error("Failed to allocate new part data.");
memcpy(parts_new, s->parts, sizeof(struct part) * offset);
memcpy(xparts_new, s->xparts, sizeof(struct xpart) * offset);
free(s->parts);
free(s->xparts);
s->parts = parts_new;
s->xparts = xparts_new;
}
/* Collect the requests for the particle data from the proxies. */
int nr_in = 0, nr_out = 0;
for (int k = 0; k < e->nr_proxies; k++) {
if (e->proxies[k].nr_parts_in > 0) {
reqs_in[2 * k] = e->proxies[k].req_parts_in;
reqs_in[2 * k + 1] = e->proxies[k].req_xparts_in;
nr_in += 1;
} else
reqs_in[2 * k] = reqs_in[2 * k + 1] = MPI_REQUEST_NULL;
if (e->proxies[k].nr_parts_out > 0) {
reqs_out[2 * k] = e->proxies[k].req_parts_out;
reqs_out[2 * k + 1] = e->proxies[k].req_xparts_out;
nr_out += 1;
} else
reqs_out[2 * k] = reqs_out[2 * k + 1] = MPI_REQUEST_NULL;
}
/* Wait for each part array to come in and collect the new
parts from the proxies. */
size_t count = 0;
for (int k = 0; k < 2 * (nr_in + nr_out); k++) {
int err, pid;
if ((err = MPI_Waitany(2 * e->nr_proxies, reqs_in, &pid,
MPI_STATUS_IGNORE)) != MPI_SUCCESS) {
char buff[MPI_MAX_ERROR_STRING];
int res;
MPI_Error_string(err, buff, &res);
error("MPI_Waitany failed (%s).", buff);
}
if (pid == MPI_UNDEFINED) break;
// message( "request from proxy %i has arrived." , pid );
if (reqs_in[pid & ~1] == MPI_REQUEST_NULL &&
reqs_in[pid | 1] == MPI_REQUEST_NULL) {
struct proxy *p = &e->proxies[pid >> 1];
memcpy(&s->parts[offset + count], p->parts_in,
sizeof(struct part) * p->nr_parts_in);
memcpy(&s->xparts[offset + count], p->xparts_in,
sizeof(struct xpart) * p->nr_parts_in);
/* for (int k = offset; k < offset + count; k++)
message(
"received particle %lli, x=[%.3e %.3e %.3e], h=%.3e, from node %i.",
s->parts[k].id, s->parts[k].x[0], s->parts[k].x[1],
s->parts[k].x[2], s->parts[k].h, p->nodeID); */
count += p->nr_parts_in;
}
}
/* Wait for all the sends to have finished too. */
if (nr_out > 0)
if (MPI_Waitall(2 * e->nr_proxies, reqs_out, MPI_STATUSES_IGNORE) !=
MPI_SUCCESS) error("MPI_Waitall on sends failed.");
if (e->verbose)
message("took %.3f %s.", clocks_from_ticks(getticks() - tic),
clocks_getunit());
/* Return the number of harvested parts. */
return count;
#else
error("SWIFT was not compiled with MPI support.");
return 0;
#endif
}
/**
* @brief Constructs the top-level pair tasks for the first hydro loop over
*neighbours
*
* Here we construct all the tasks for all possible neighbouring non-empty
* local cells in the hierarchy. No dependencies are being added thus far.
* Additional loop over neighbours can later be added by simply duplicating
* all the tasks created by this function.
*
* @param e The #engine.
*/
void engine_make_hydroloop_tasks(struct engine *e) {
struct space *s = e->s;
struct scheduler *sched = &e->sched;
const int nodeID = e->nodeID;
const int *cdim = s->cdim;
struct cell *cells = s->cells;
/* Run through the highest level of cells and add pairs. */
for (int i = 0; i < cdim[0]; i++) {
for (int j = 0; j < cdim[1]; j++) {
for (int k = 0; k < cdim[2]; k++) {
/* Get the cell */
const int cid = cell_getid(cdim, i, j, k);
struct cell *ci = &cells[cid];
/* Skip cells without hydro particles */
if (ci->count == 0) continue;
/* If the cells is local build a self-interaction */
if (ci->nodeID == nodeID)
scheduler_addtask(sched, task_type_self, task_subtype_density, 0, 0,
ci, NULL, 0);
/* Now loop over all the neighbours of this cell */
for (int ii = -1; ii < 2; ii++) {
int iii = i + ii;
if (!s->periodic && (iii < 0 || iii >= cdim[0])) continue;
iii = (iii + cdim[0]) % cdim[0];
for (int jj = -1; jj < 2; jj++) {
int jjj = j + jj;
if (!s->periodic && (jjj < 0 || jjj >= cdim[1])) continue;
jjj = (jjj + cdim[1]) % cdim[1];
for (int kk = -1; kk < 2; kk++) {
int kkk = k + kk;
if (!s->periodic && (kkk < 0 || kkk >= cdim[2])) continue;
kkk = (kkk + cdim[2]) % cdim[2];
/* Get the neighbouring cell */
const int cjd = cell_getid(cdim, iii, jjj, kkk);
struct cell *cj = &cells[cjd];
/* Is that neighbour local and does it have particles ? */ if (cid >= cjd || cj->count == 0 ||
(ci->nodeID != nodeID && cj->nodeID != nodeID))
continue;
/* Construct the pair task */
const int sid =
sortlistID[(kk + 1) + 3 * ((jj + 1) + 3 * (ii + 1))];
scheduler_addtask(sched, task_type_pair, task_subtype_density,
sid, 0, ci, cj, 1);
}
}
}
}
}
}
}
/**
* @brief Counts the tasks associated with one cell and constructs the links
*
* For each hydrodynamic task, construct the links with the corresponding cell.
* Similarly, construct the dependencies for all the sorting tasks.
*
* @param e The #engine.
*/
void engine_count_and_link_tasks(struct engine *e) {
struct scheduler *sched = &e->sched;
const int nr_tasks = sched->nr_tasks;
for (int k = 0; k < nr_tasks; k++) {
/* Get the current task. */
struct task *t = &sched->tasks[k];
if (t->skip) continue;
/* Link sort tasks together. */
if (t->type == task_type_sort && t->ci->split)
for (int j = 0; j < 8; j++)
if (t->ci->progeny[j] != NULL && t->ci->progeny[j]->sorts != NULL) {
t->ci->progeny[j]->sorts->skip = 0;
scheduler_addunlock(sched, t->ci->progeny[j]->sorts, t);
}
/* Link density tasks to cells. */
if (t->type == task_type_self) {
atomic_inc(&t->ci->nr_tasks);
if (t->subtype == task_subtype_density) {
t->ci->density = engine_addlink(e, t->ci->density, t);
atomic_inc(&t->ci->nr_density);
}
} else if (t->type == task_type_pair) {
atomic_inc(&t->ci->nr_tasks);
atomic_inc(&t->cj->nr_tasks);
if (t->subtype == task_subtype_density) {
t->ci->density = engine_addlink(e, t->ci->density, t);
atomic_inc(&t->ci->nr_density);
t->cj->density = engine_addlink(e, t->cj->density, t);
atomic_inc(&t->cj->nr_density);
}
} else if (t->type == task_type_sub) {
atomic_inc(&t->ci->nr_tasks);
if (t->cj != NULL) atomic_inc(&t->cj->nr_tasks);
if (t->subtype == task_subtype_density) {
t->ci->density = engine_addlink(e, t->ci->density, t);
atomic_inc(&t->ci->nr_density);
if (t->cj != NULL) {
t->cj->density = engine_addlink(e, t->cj->density, t);
atomic_inc(&t->cj->nr_density);
} }
}
/* /\* Link gravity multipole tasks to the up/down tasks. *\/ */
/* if (t->type == task_type_grav_mm || */
/* (t->type == task_type_sub && t->subtype == task_subtype_grav)) { */
/* atomic_inc(&t->ci->nr_tasks); */
/* scheduler_addunlock(sched, t->ci->grav_up, t); */
/* scheduler_addunlock(sched, t, t->ci->grav_down); */
/* if (t->cj != NULL && t->ci->grav_up != t->cj->grav_up) { */
/* scheduler_addunlock(sched, t->cj->grav_up, t); */
/* scheduler_addunlock(sched, t, t->cj->grav_down); */
/* } */
/* } */
}
}
/**
* @brief Duplicates the first hydro loop and construct all the
* dependencies for the hydro part
*
* This is done by looping over all the previously constructed tasks
* and adding another task involving the same cells but this time
* corresponding to the second hydro loop over neighbours.
* With all the relevant tasks for a given cell available, we construct
* all the dependencies for that cell.
*
* @param e The #engine.
*/
void engine_make_extra_hydroloop_tasks(struct engine *e) {
struct scheduler *sched = &e->sched;
const int nodeID = e->nodeID;
const int nr_tasks = sched->nr_tasks;
for (int k = 0; k < nr_tasks; k++) {
/* Get a pointer to the task. */
struct task *t = &sched->tasks[k];
/* Skip? */
if (t->skip) continue;
/* Self-interaction? */
if (t->type == task_type_self && t->subtype == task_subtype_density) {
/* Start by constructing the task for the second hydro loop */
struct task *t2 = scheduler_addtask(
sched, task_type_self, task_subtype_force, 0, 0, t->ci, NULL, 0);
/* Add the link between the new loop and the cell */
t->ci->force = engine_addlink(e, t->ci->force, t2);
atomic_inc(&t->ci->nr_force);
/* Now, build all the dependencies for the hydro */
/* init --> t (density loop) --> ghost --> t2 (force loop) --> kick */
scheduler_addunlock(sched, t->ci->super->init, t);
scheduler_addunlock(sched, t, t->ci->super->ghost);
scheduler_addunlock(sched, t->ci->super->ghost, t2);
scheduler_addunlock(sched, t2, t->ci->super->kick);
}
/* Otherwise, pair interaction? */
else if (t->type == task_type_pair && t->subtype == task_subtype_density) {
/* Start by constructing the task for the second hydro loop */
struct task *t2 = scheduler_addtask(
sched, task_type_pair, task_subtype_force, 0, 0, t->ci, t->cj, 0);
/* Add the link between the new loop and both cells */ t->ci->force = engine_addlink(e, t->ci->force, t2);
atomic_inc(&t->ci->nr_force);
t->cj->force = engine_addlink(e, t->cj->force, t2);
atomic_inc(&t->cj->nr_force);
/* Now, build all the dependencies for the hydro for the cells */
/* that are local and are not descendant of the same super-cells */
/* init --> t (density loop) --> ghost --> t2 (force loop) --> kick */
if (t->ci->nodeID == nodeID) {
scheduler_addunlock(sched, t->ci->super->init, t);
scheduler_addunlock(sched, t, t->ci->super->ghost);
scheduler_addunlock(sched, t->ci->super->ghost, t2);
scheduler_addunlock(sched, t2, t->ci->super->kick);
}
if (t->cj->nodeID == nodeID && t->ci->super != t->cj->super) {
scheduler_addunlock(sched, t->cj->super->init, t);
scheduler_addunlock(sched, t, t->cj->super->ghost);
scheduler_addunlock(sched, t->cj->super->ghost, t2);
scheduler_addunlock(sched, t2, t->cj->super->kick);
}
}
/* Otherwise, sub interaction? */
else if (t->type == task_type_sub && t->subtype == task_subtype_density) {
/* Start by constructing the task for the second hydro loop */
struct task *t2 =
scheduler_addtask(sched, task_type_sub, task_subtype_force, t->flags,
0, t->ci, t->cj, 0);
/* Add the link between the new loop and both cells */
t->ci->force = engine_addlink(e, t->ci->force, t2);
atomic_inc(&t->ci->nr_force);
if (t->cj != NULL) {
t->cj->force = engine_addlink(e, t->cj->force, t2);
atomic_inc(&t->cj->nr_force);
}
/* Now, build all the dependencies for the hydro for the cells */
/* that are local and are not descendant of the same super-cells */
/* init --> t (density loop) --> ghost --> t2 (force loop) --> kick */
if (t->ci->nodeID == nodeID) {
scheduler_addunlock(sched, t, t->ci->super->ghost);
scheduler_addunlock(sched, t->ci->super->ghost, t2);
scheduler_addunlock(sched, t2, t->ci->super->kick);
}
if (t->cj != NULL && t->cj->nodeID == nodeID &&
t->ci->super != t->cj->super) {
scheduler_addunlock(sched, t, t->cj->super->ghost);
scheduler_addunlock(sched, t->cj->super->ghost, t2);
scheduler_addunlock(sched, t2, t->cj->super->kick);
}
}
/* /\* Kick tasks should rely on the grav_down tasks of their cell. *\/ */
/* else if (t->type == task_type_kick && t->ci->grav_down != NULL) */
/* scheduler_addunlock(sched, t->ci->grav_down, t); */
}
}
/**
* @brief Constructs the top-level pair tasks for the gravity M-M interactions
*
* Correct implementation is still lacking here.
*
* @param e The #engine.
*/
void engine_make_gravityinteraction_tasks(struct engine *e) {
struct space *s = e->s; struct scheduler *sched = &e->sched;
const int nr_cells = s->nr_cells;
struct cell *cells = s->cells;
/* Loop over all cells. */
for (int i = 0; i < nr_cells; i++) {
/* If it has gravity particles, add a self-task */
if (cells[i].gcount > 0) {
scheduler_addtask(sched, task_type_grav_mm, task_subtype_none, -1, 0,
&cells[i], NULL, 0);
/* Loop over all remainding cells */
for (int j = i + 1; j < nr_cells; j++) {
/* If that other cell has gravity parts, add a pair interaction */
if (cells[j].gcount > 0) {
scheduler_addtask(sched, task_type_grav_mm, task_subtype_none, -1, 0,
&cells[i], &cells[j], 0);
}
}
}
}
}
/**
* @brief Constructs the gravity tasks building the multipoles and propagating
*them to the children
*
* Correct implementation is still lacking here.
*
* @param e The #engine.
*/
void engine_make_gravityrecursive_tasks(struct engine *e) {
struct space *s = e->s;
struct scheduler *sched = &e->sched;
const int nodeID = e->nodeID;
const int nr_cells = s->nr_cells;
struct cell *cells = s->cells;
for (int k = 0; k < nr_cells; k++) {
/* Only do this for local cells containing gravity particles */
if (cells[k].nodeID == nodeID && cells[k].gcount > 0) {
/* Create tasks at top level. */
struct task *up =
scheduler_addtask(sched, task_type_grav_up, task_subtype_none, 0, 0,
&cells[k], NULL, 0);
struct task *down =
scheduler_addtask(sched, task_type_grav_down, task_subtype_none, 0, 0,
&cells[k], NULL, 0);
/* Push tasks down the cell hierarchy. */
engine_addtasks_grav(e, &cells[k], up, down);
}
}
}
/**
* @brief Fill the #space's task list.
*
* @param e The #engine we are working with.
*/
void engine_maketasks(struct engine *e) {
struct space *s = e->s;
struct scheduler *sched = &e->sched;
struct cell *cells = s->cells; const int nr_cells = s->nr_cells;
const ticks tic = getticks();
/* Re-set the scheduler. */
scheduler_reset(sched, s->tot_cells * engine_maxtaskspercell);
/* Add the space sorting tasks. */
for (int i = 0; i < e->nr_threads; i++)
scheduler_addtask(sched, task_type_psort, task_subtype_none, i, 0, NULL,
NULL, 0);
/* Construct the firt hydro loop over neighbours */
engine_make_hydroloop_tasks(e);
/* Add the gravity mm tasks. */
if ((e->policy & engine_policy_self_gravity) == engine_policy_self_gravity)
engine_make_gravityinteraction_tasks(e);
/* Split the tasks. */
scheduler_splittasks(sched);
/* Allocate the list of cell-task links. The maximum number of links
is the number of cells (s->tot_cells) times the number of neighbours (27)
times the number of interaction types (2, density and force). */
if (e->links != NULL) free(e->links);
e->size_links = s->tot_cells * 27 * 2;
if ((e->links = malloc(sizeof(struct link) * e->size_links)) == NULL)
error("Failed to allocate cell-task links.");
e->nr_links = 0;
/* Add the gravity up/down tasks at the top-level cells and push them down. */
if ((e->policy & engine_policy_self_gravity) == engine_policy_self_gravity)
engine_make_gravityrecursive_tasks(e);
/* Count the number of tasks associated with each cell and
store the density tasks in each cell, and make each sort
depend on the sorts of its progeny. */
engine_count_and_link_tasks(e);
/* Append a ghost task to each cell, and add kick tasks to the
super cells. */
for (int k = 0; k < nr_cells; k++)
engine_make_ghost_tasks(e, &cells[k], NULL);
/* Run through the tasks and make force tasks for each density task.
Each force task depends on the cell ghosts and unlocks the kick task
of its super-cell. */
engine_make_extra_hydroloop_tasks(e);
/* Add the communication tasks if MPI is being used. */
if ((e->policy & engine_policy_mpi) == engine_policy_mpi) {
/* Loop over the proxies. */
for (int pid = 0; pid < e->nr_proxies; pid++) {
/* Get a handle on the proxy. */
struct proxy *p = &e->proxies[pid];
/* Loop through the proxy's incoming cells and add the
recv tasks. */
for (int k = 0; k < p->nr_cells_in; k++)
engine_addtasks_recv(e, p->cells_in[k], NULL, NULL);
/* Loop through the proxy's outgoing cells and add the
send tasks. */
for (int k = 0; k < p->nr_cells_out; k++)
engine_addtasks_send(e, p->cells_out[k], p->cells_in[0]);
}
}
/* Set the unlocks per task. */
scheduler_set_unlocks(sched);
/* Rank the tasks. */
scheduler_ranktasks(sched);
/* Weight the tasks. */
scheduler_reweight(sched);
/* Set the tasks age. */
e->tasks_age = 0;
if (e->verbose)
message("took %.3f %s.", clocks_from_ticks(getticks() - tic),
clocks_getunit());
}
/**
* @brief Mark tasks to be skipped and set the sort flags accordingly.
*
* @return 1 if the space has to be rebuilt, 0 otherwise.
*/
int engine_marktasks(struct engine *e) {
struct scheduler *s = &e->sched;
const int ti_end = e->ti_current;
const int nr_tasks = s->nr_tasks;
const int *const ind = s->tasks_ind;
struct task *tasks = s->tasks;
const ticks tic = getticks();
/* Much less to do here if we're on a fixed time-step. */
if ((e->policy & engine_policy_fixdt) == engine_policy_fixdt) {
/* Run through the tasks and mark as skip or not. */
for (int k = 0; k < nr_tasks; k++) {
/* Get a handle on the kth task. */
struct task *t = &tasks[ind[k]];
/* Pair? */
if (t->type == task_type_pair ||
(t->type == task_type_sub && t->cj != NULL)) {
/* Local pointers. */
const struct cell *ci = t->ci;
const struct cell *cj = t->cj;
/* Too much particle movement? */
if (t->tight &&
(fmaxf(ci->h_max, cj->h_max) + ci->dx_max + cj->dx_max > cj->dmin ||
ci->dx_max > space_maxreldx * ci->h_max ||
cj->dx_max > space_maxreldx * cj->h_max))
return 1;
}
/* Sort? */
else if (t->type == task_type_sort) {
/* If all the sorts have been done, make this task implicit. */
if (!(t->flags & (t->flags ^ t->ci->sorted))) t->implicit = 1;
}
}
/* Multiple-timestep case */
} else {
/* Run through the tasks and mark as skip or not. */ for (int k = 0; k < nr_tasks; k++) {
/* Get a handle on the kth task. */
struct task *t = &tasks[ind[k]];
/* Sort-task? Note that due to the task ranking, the sorts
will all come before the pairs. */
if (t->type == task_type_sort) {
/* Re-set the flags. */
t->flags = 0;
t->skip = 1;
}
/* Single-cell task? */
else if (t->type == task_type_self || t->type == task_type_ghost ||
(t->type == task_type_sub && t->cj == NULL)) {
/* Set this task's skip. */
t->skip = (t->ci->ti_end_min > ti_end);
}
/* Pair? */
else if (t->type == task_type_pair ||
(t->type == task_type_sub && t->cj != NULL)) {
/* Local pointers. */
const struct cell *ci = t->ci;
const struct cell *cj = t->cj;
/* Set this task's skip. */
t->skip = (ci->ti_end_min > ti_end && cj->ti_end_min > ti_end);
/* Too much particle movement? */
if (t->tight &&
(fmaxf(ci->h_max, cj->h_max) + ci->dx_max + cj->dx_max > cj->dmin ||
ci->dx_max > space_maxreldx * ci->h_max ||
cj->dx_max > space_maxreldx * cj->h_max))
return 1;
/* Set the sort flags. */
if (!t->skip && t->type == task_type_pair) {
if (!(ci->sorted & (1 << t->flags))) {
ci->sorts->flags |= (1 << t->flags);
ci->sorts->skip = 0;
}
if (!(cj->sorted & (1 << t->flags))) {
cj->sorts->flags |= (1 << t->flags);
cj->sorts->skip = 0;
}
}
}
/* Kick? */
else if (t->type == task_type_kick) {
t->skip = (t->ci->ti_end_min > ti_end);
t->ci->updated = 0;
}
/* Drift? */
else if (t->type == task_type_drift)
t->skip = 0;
/* Init? */
else if (t->type == task_type_init) {
/* Set this task's skip. */
t->skip = (t->ci->ti_end_min > ti_end);
}
/* None? */
else if (t->type == task_type_none)
t->skip = 1;
}
}
if (e->verbose)
message("took %.3f %s.", clocks_from_ticks(getticks() - tic),
clocks_getunit());
/* All is well... */
return 0;
}
/**
* @brief Prints the number of tasks in the engine
*
* @param e The #engine.
*/
void engine_print_task_counts(struct engine *e) {
struct scheduler *sched = &e->sched;
/* Count and print the number of each task type. */
int counts[task_type_count + 1];
for (int k = 0; k <= task_type_count; k++) counts[k] = 0;
for (int k = 0; k < sched->nr_tasks; k++)
if (!sched->tasks[k].skip)
counts[(int)sched->tasks[k].type] += 1;
else
counts[task_type_count] += 1;
#ifdef WITH_MPI
printf("[%04i] %s engine_print_task_counts: task counts are [ %s=%i",
e->nodeID, clocks_get_timesincestart(), taskID_names[0], counts[0]);
#else
printf("%s engine_print_task_counts: task counts are [ %s=%i",
clocks_get_timesincestart(), taskID_names[0], counts[0]);
#endif
for (int k = 1; k < task_type_count; k++)
printf(" %s=%i", taskID_names[k], counts[k]);
printf(" skipped=%i ]\n", counts[task_type_count]);
fflush(stdout);
message("nr_parts = %zi.", e->s->nr_parts);
}
/**
* @brief Rebuild the space and tasks.
*
* @param e The #engine.
*/
void engine_rebuild(struct engine *e) {
const ticks tic = getticks();
/* Clear the forcerebuild flag, whatever it was. */
e->forcerebuild = 0;
/* Re-build the space. */
space_rebuild(e->s, 0.0, e->verbose);
/* If in parallel, exchange the cell structure. */
#ifdef WITH_MPI
engine_exchange_cells(e);
#endif
/* Re-build the tasks. */
engine_maketasks(e);
/* Run through the tasks and mark as skip or not. */
if (engine_marktasks(e))
error("engine_marktasks failed after space_rebuild.");
/* Print the status of the system */
engine_print_task_counts(e);
if (e->verbose)
message("took %.3f %s.", clocks_from_ticks(getticks() - tic),
clocks_getunit());
}
/**
* @brief Prepare the #engine by re-building the cells and tasks.
*
* @param e The #engine to prepare.
*/
void engine_prepare(struct engine *e) {
TIMER_TIC;
/* Run through the tasks and mark as skip or not. */
int rebuild = (e->forcerebuild || engine_marktasks(e));
/* Collect the values of rebuild from all nodes. */
#ifdef WITH_MPI
int buff;
if (MPI_Allreduce(&rebuild, &buff, 1, MPI_INT, MPI_MAX, MPI_COMM_WORLD) !=
MPI_SUCCESS)
error("Failed to aggregate the rebuild flag across nodes.");
rebuild = buff;
#endif
e->tic_step = getticks();
/* Did this not go through? */
if (rebuild) {
engine_rebuild(e);
}
/* Re-rank the tasks every now and then. */
if (e->tasks_age % engine_tasksreweight == 1) {
scheduler_reweight(&e->sched);
}
e->tasks_age += 1;
TIMER_TOC(timer_prepare);
if (e->verbose)
message("took %.3f %s.", clocks_from_ticks(getticks() - tic),
clocks_getunit());
}
/**
* @brief Implements a barrier for the #runner threads.
*
* @param e The #engine.
* @param tid The thread ID
*/
void engine_barrier(struct engine *e, int tid) {
/* First, get the barrier mutex. */
if (pthread_mutex_lock(&e->barrier_mutex) != 0)
error("Failed to get barrier mutex.");
/* This thread is no longer running. */
e->barrier_running -= 1;
/* If all threads are in, send a signal... */
if (e->barrier_running == 0)
if (pthread_cond_broadcast(&e->barrier_cond) != 0)
error("Failed to broadcast barrier full condition.");
/* Wait for the barrier to open. */
while (e->barrier_launch == 0 || tid >= e->barrier_launchcount)
if (pthread_cond_wait(&e->barrier_cond, &e->barrier_mutex) != 0)
error("Error waiting for barrier to close.");
/* This thread has been launched. */
e->barrier_running += 1;
e->barrier_launch -= 1;
/* If I'm the last one out, signal the condition again. */
if (e->barrier_launch == 0)
if (pthread_cond_broadcast(&e->barrier_cond) != 0)
error("Failed to broadcast empty barrier condition.");
/* Last but not least, release the mutex. */
if (pthread_mutex_unlock(&e->barrier_mutex) != 0)
error("Failed to get unlock the barrier mutex.");
}
/**
* @brief Mapping function to collect the data from the kick.
*/
void engine_collect_kick(struct cell *c) {
/* Skip super-cells (Their values are already set) */
if (c->kick != NULL) return;
/* Counters for the different quantities. */
int updated = 0;
double e_kin = 0.0, e_int = 0.0, e_pot = 0.0;
float mom[3] = {0.0f, 0.0f, 0.0f}, ang[3] = {0.0f, 0.0f, 0.0f};
int ti_end_min = max_nr_timesteps, ti_end_max = 0;
/* Only do something is the cell is non-empty */
if (c->count != 0) {
/* If this cell is not split, I'm in trouble. */
if (!c->split) error("Cell has no super-cell.");
/* Collect the values from the progeny. */
for (int k = 0; k < 8; k++) {
struct cell *cp = c->progeny[k];
if (cp != NULL) {
/* Recurse */
engine_collect_kick(cp);
/* And update */
ti_end_min = min(ti_end_min, cp->ti_end_min);
ti_end_max = max(ti_end_max, cp->ti_end_max);
updated += cp->updated;
e_kin += cp->e_kin;
e_int += cp->e_int;
e_pot += cp->e_pot;
mom[0] += cp->mom[0];
mom[1] += cp->mom[1];
mom[2] += cp->mom[2];
ang[0] += cp->ang[0];
ang[1] += cp->ang[1];
ang[2] += cp->ang[2];
}
}
}
/* Store the collected values in the cell. */
c->ti_end_min = ti_end_min;
c->ti_end_max = ti_end_max;
c->updated = updated;
c->e_kin = e_kin;
c->e_int = e_int;
c->e_pot = e_pot;
c->mom[0] = mom[0];
c->mom[1] = mom[1];
c->mom[2] = mom[2];
c->ang[0] = ang[0];
c->ang[1] = ang[1];
c->ang[2] = ang[2];
}
/**
* @brief Launch the runners.
*
* @param e The #engine.
* @param nr_runners The number of #runner to let loose.
* @param mask The task mask to launch.
* @param submask The sub-task mask to launch.
*/
void engine_launch(struct engine *e, int nr_runners, unsigned int mask,
unsigned int submask) {
/* Prepare the scheduler. */
atomic_inc(&e->sched.waiting);
/* Cry havoc and let loose the dogs of war. */
e->barrier_launch = nr_runners;
e->barrier_launchcount = nr_runners;
if (pthread_cond_broadcast(&e->barrier_cond) != 0)
error("Failed to broadcast barrier open condition.");
/* Load the tasks. */
pthread_mutex_unlock(&e->barrier_mutex);
scheduler_start(&e->sched, mask, submask);
pthread_mutex_lock(&e->barrier_mutex);
/* Remove the safeguard. */
pthread_mutex_lock(&e->sched.sleep_mutex);
atomic_dec(&e->sched.waiting);
pthread_cond_broadcast(&e->sched.sleep_cond);
pthread_mutex_unlock(&e->sched.sleep_mutex);
/* Sit back and wait for the runners to come home. */
while (e->barrier_launch || e->barrier_running)
if (pthread_cond_wait(&e->barrier_cond, &e->barrier_mutex) != 0)
error("Error while waiting for barrier.");
}
/**
* @brief Initialises the particles and set them in a state ready to move
*forward in time.
*
* @param e The #engine
*/
void engine_init_particles(struct engine *e) {
struct space *s = e->s;
if (e->nodeID == 0) message("Initialising particles");
/* Make sure all particles are ready to go */
/* i.e. clean-up any stupid state in the ICs */
space_map_cells_pre(s, 1, cell_init_parts, NULL);
engine_prepare(e);
engine_marktasks(e);
// printParticle(e->s->parts, 1000, e->s->nr_parts);
// printParticle(e->s->parts, 515050, e->s->nr_parts);
// message("\n0th DENSITY CALC\n");
/* Build the masks corresponding to the policy */
unsigned int mask = 0;
unsigned int submask = 0;
/* We always have sort tasks */
mask |= 1 << task_type_sort;
/* Add the tasks corresponding to hydro operations to the masks */
if ((e->policy & engine_policy_hydro) == engine_policy_hydro) {
mask |= 1 << task_type_init;
mask |= 1 << task_type_self;
mask |= 1 << task_type_pair;
mask |= 1 << task_type_sub;
mask |= 1 << task_type_ghost;
submask |= 1 << task_subtype_density;
}
/* Add the tasks corresponding to self-gravity to the masks */
if ((e->policy & engine_policy_self_gravity) == engine_policy_self_gravity) {
/* Nothing here for now */
}
/* Add the tasks corresponding to self-gravity to the masks */
if ((e->policy & engine_policy_external_gravity) ==
engine_policy_external_gravity) {
/* Nothing here for now */
}
/* Add MPI tasks if need be */
if ((e->policy & engine_policy_mpi) == engine_policy_mpi) {
mask |= 1 << task_type_send;
mask |= 1 << task_type_recv;
}
/* Now, launch the calculation */
TIMER_TIC;
engine_launch(e, e->nr_threads, mask, submask);
TIMER_TOC(timer_runners);
// message("\n0th ENTROPY CONVERSION\n")
/* Apply some conversions (e.g. internal energy -> entropy) */
space_map_cells_pre(s, 1, cell_convert_hydro, NULL);
// printParticle(e->s->parts, e->s->xparts,1000, e->s->nr_parts);
// printParticle(e->s->parts, e->s->xparts,515050, e->s->nr_parts);
/* Ready to go */
e->step = -1;
}
/**
* @brief Let the #engine loose to compute the forces.
*
* @param e The #engine.
*/
void engine_step(struct engine *e) {
int updates = 0;
int ti_end_min = max_nr_timesteps, ti_end_max = 0;
double e_pot = 0.0, e_int = 0.0, e_kin = 0.0;
float mom[3] = {0.0, 0.0, 0.0};
float ang[3] = {0.0, 0.0, 0.0};
struct space *s = e->s;
TIMER_TIC2;
struct clocks_time time1, time2;
clocks_gettime(&time1);
/* Collect the cell data. */
for (int k = 0; k < s->nr_cells; k++)
if (s->cells[k].nodeID == e->nodeID) {
struct cell *c = &s->cells[k];
/* Recurse */
engine_collect_kick(c);
/* And aggregate */
ti_end_min = min(ti_end_min, c->ti_end_min);
ti_end_max = max(ti_end_max, c->ti_end_max);
e_kin += c->e_kin;
e_int += c->e_int;
e_pot += c->e_pot;
updates += c->updated;
mom[0] += c->mom[0];
mom[1] += c->mom[1];
mom[2] += c->mom[2];
ang[0] += c->ang[0];
ang[1] += c->ang[1];
ang[2] += c->ang[2];
}
/* Aggregate the data from the different nodes. */
#ifdef WITH_MPI
{
int in_i[4], out_i[4];
out_i[0] = ti_end_min;
if (MPI_Allreduce(out_i, in_i, 1, MPI_INT, MPI_MIN, MPI_COMM_WORLD) !=
MPI_SUCCESS)
error("Failed to aggregate t_end_min.");
ti_end_min = in_i[0];
out_i[0] = ti_end_max;
if (MPI_Allreduce(out_i, in_i, 1, MPI_INT, MPI_MAX, MPI_COMM_WORLD) !=
MPI_SUCCESS)
error("Failed to aggregate t_end_max.");
ti_end_max = in_i[0];
}
{
double in_d[4], out_d[4];
out_d[0] = updates;
out_d[1] = e_kin;
out_d[2] = e_int;
out_d[3] = e_pot;
if (MPI_Allreduce(out_d, in_d, 4, MPI_DOUBLE, MPI_SUM, MPI_COMM_WORLD) !=
MPI_SUCCESS)
error("Failed to aggregate energies.");
updates = in_d[0];
e_kin = in_d[1];
e_int = in_d[2];
e_pot = in_d[3];
}
#endif
// message("\nDRIFT\n");
/* Move forward in time */ e->ti_old = e->ti_current;
e->ti_current = ti_end_min;
e->step += 1;
e->time = e->ti_current * e->timeBase + e->timeBegin;
e->timeOld = e->ti_old * e->timeBase + e->timeBegin;
e->timeStep = (e->ti_current - e->ti_old) * e->timeBase;
/* Drift everybody */
engine_launch(e, e->nr_threads, 1 << task_type_drift, 0);
// printParticle(e->s->parts, e->s->xparts, 1000, e->s->nr_parts);
// printParticle(e->s->parts, e->s->xparts, 515050, e->s->nr_parts);
// if(e->step == 2) exit(0);
if (e->nodeID == 0) {
/* Print some information to the screen */
printf("%d %e %e %d %.3f\n", e->step, e->time, e->timeStep, updates,
e->wallclock_time);
fflush(stdout);
/* Write some energy statistics */
fprintf(e->file_stats, "%d %f %f %f %f %f %f %f %f %f %f %f\n", e->step,
e->time, e_kin, e_int, e_pot, e_kin + e_int + e_pot, mom[0], mom[1],
mom[2], ang[0], ang[1], ang[2]);
fflush(e->file_stats);
}
// message("\nACCELERATION AND KICK\n");
/* Re-distribute the particles amongst the nodes? */
if (e->forcerepart != REPART_NONE) engine_repartition(e);
/* Prepare the space. */
engine_prepare(e);
/* Build the masks corresponding to the policy */
unsigned int mask = 0, submask = 0;
/* We always have sort tasks and kick tasks */
mask |= 1 << task_type_sort;
mask |= 1 << task_type_kick;
/* Add the tasks corresponding to hydro operations to the masks */
if ((e->policy & engine_policy_hydro) == engine_policy_hydro) {
mask |= 1 << task_type_init;
mask |= 1 << task_type_self;
mask |= 1 << task_type_pair;
mask |= 1 << task_type_sub;
mask |= 1 << task_type_ghost;
submask |= 1 << task_subtype_density;
submask |= 1 << task_subtype_force;
}
/* Add the tasks corresponding to self-gravity to the masks */
if ((e->policy & engine_policy_self_gravity) == engine_policy_self_gravity) {
/* Nothing here for now */
}
/* Add the tasks corresponding to self-gravity to the masks */
if ((e->policy & engine_policy_external_gravity) ==
engine_policy_external_gravity) {
/* Nothing here for now */
}
/* Add MPI tasks if need be */
if ((e->policy & engine_policy_mpi) == engine_policy_mpi) {
mask |= 1 << task_type_send;
mask |= 1 << task_type_recv;
}
/* Send off the runners. */
TIMER_TIC;
engine_launch(e, e->nr_threads, mask, submask);
TIMER_TOC(timer_runners);
TIMER_TOC2(timer_step);
clocks_gettime(&time2);
e->wallclock_time = (float)clocks_diff(&time1, &time2);
// printParticle(e->s->parts, e->s->xparts,1000, e->s->nr_parts);
// printParticle(e->s->parts, e->s->xparts,515050, e->s->nr_parts);
}
/**
* @brief Returns 1 if the simulation has reached its end point, 0 otherwise
*/
int engine_is_done(struct engine *e) {
return !(e->ti_current < max_nr_timesteps);
}
/**
* @brief Create and fill the proxies.
*
* @param e The #engine.
*/
void engine_makeproxies(struct engine *e) {
#ifdef WITH_MPI
const int *cdim = e->s->cdim;
const struct space *s = e->s;
struct cell *cells = s->cells;
struct proxy *proxies = e->proxies;
ticks tic = getticks();
/* Prepare the proxies and the proxy index. */
if (e->proxy_ind == NULL)
if ((e->proxy_ind = (int *)malloc(sizeof(int) * e->nr_nodes)) == NULL)
error("Failed to allocate proxy index.");
for (int k = 0; k < e->nr_nodes; k++) e->proxy_ind[k] = -1;
e->nr_proxies = 0;
/* The following loop is super-clunky, but it's necessary
to ensure that the order of the send and recv cells in
the proxies is identical for all nodes! */
/* Loop over each cell in the space. */
int ind[3];
for (ind[0] = 0; ind[0] < cdim[0]; ind[0]++)
for (ind[1] = 0; ind[1] < cdim[1]; ind[1]++)
for (ind[2] = 0; ind[2] < cdim[2]; ind[2]++) {
/* Get the cell ID. */
const int cid = cell_getid(cdim, ind[0], ind[1], ind[2]);
/* Loop over all its neighbours (periodic). */
for (int i = -1; i <= 1; i++) {
int ii = ind[0] + i;
if (ii >= cdim[0])
ii -= cdim[0];
else if (ii < 0)
ii += cdim[0]; for (int j = -1; j <= 1; j++) {
int jj = ind[1] + j;
if (jj >= cdim[1])
jj -= cdim[1];
else if (jj < 0)
jj += cdim[1];
for (int k = -1; k <= 1; k++) {
int kk = ind[2] + k;
if (kk >= cdim[2])
kk -= cdim[2];
else if (kk < 0)
kk += cdim[2];
/* Get the cell ID. */
const int cjd = cell_getid(cdim, ii, jj, kk);
/* Add to proxies? */
if (cells[cid].nodeID == e->nodeID &&
cells[cjd].nodeID != e->nodeID) {
int pid = e->proxy_ind[cells[cjd].nodeID];
if (pid < 0) {
if (e->nr_proxies == engine_maxproxies)
error("Maximum number of proxies exceeded.");
proxy_init(&proxies[e->nr_proxies], e->nodeID,
cells[cjd].nodeID);
e->proxy_ind[cells[cjd].nodeID] = e->nr_proxies;
pid = e->nr_proxies;
e->nr_proxies += 1;
}
proxy_addcell_in(&proxies[pid], &cells[cjd]);
proxy_addcell_out(&proxies[pid], &cells[cid]);
cells[cid].sendto |= (1ULL << pid);
}
if (cells[cjd].nodeID == e->nodeID &&
cells[cid].nodeID != e->nodeID) {
int pid = e->proxy_ind[cells[cid].nodeID];
if (pid < 0) {
if (e->nr_proxies == engine_maxproxies)
error("Maximum number of proxies exceeded.");
proxy_init(&proxies[e->nr_proxies], e->nodeID,
cells[cid].nodeID);
e->proxy_ind[cells[cid].nodeID] = e->nr_proxies;
pid = e->nr_proxies;
e->nr_proxies += 1;
}
proxy_addcell_in(&proxies[pid], &cells[cid]);
proxy_addcell_out(&proxies[pid], &cells[cjd]);
cells[cjd].sendto |= (1ULL << pid);
}
}
}
}
}
if (e->verbose)
message("took %.3f %s.", clocks_from_ticks(getticks() - tic),
clocks_getunit());
#else
error("SWIFT was not compiled with MPI support.");
#endif
}
/**
* @brief Split the underlying space into regions and assign to separate nodes.
*
* @param e The #engine.
* @param initial_partition structure defining the cell partition technique
*/
void engine_split(struct engine *e, struct partition *initial_partition) {
#ifdef WITH_MPI
struct space *s = e->s;
/* Do the initial partition of the cells. */
partition_initial_partition(initial_partition, e->nodeID, e->nr_nodes, s);
/* Make the proxies. */
engine_makeproxies(e);
/* Re-allocate the local parts. */
if (e->nodeID == 0)
message("Re-allocating parts array from %zi to %zi.", s->size_parts,
(size_t)(s->nr_parts * 1.2));
s->size_parts = s->nr_parts * 1.2;
struct part *parts_new = NULL;
struct xpart *xparts_new = NULL;
if (posix_memalign((void **)&parts_new, part_align,
sizeof(struct part) * s->size_parts) != 0 ||
posix_memalign((void **)&xparts_new, part_align,
sizeof(struct xpart) * s->size_parts) != 0)
error("Failed to allocate new part data.");
memcpy(parts_new, s->parts, sizeof(struct part) * s->nr_parts);
memcpy(xparts_new, s->xparts, sizeof(struct xpart) * s->nr_parts);
free(s->parts);
free(s->xparts);
s->parts = parts_new;
s->xparts = xparts_new;
#else
error("SWIFT was not compiled with MPI support.");
#endif
}
#if defined(HAVE_LIBNUMA) && defined(_GNU_SOURCE)
static bool hyperthreads_present(void) {
#ifdef __linux__
FILE *f =
fopen("/sys/devices/system/cpu/cpu0/topology/thread_siblings_list", "r");
int c;
while ((c = fgetc(f)) != EOF && c != ',')
;
fclose(f);
return c == ',';
#else
return true; // just guess
#endif
}
#endif
/**
* @brief init an engine with the given number of threads, queues, and
* the given policy.
*
* @param e The #engine.
* @param s The #space in which this #runner will run.
* @param dt The initial time step to use.
* @param nr_threads The number of threads to spawn.
* @param nr_queues The number of task queues to create.
* @param nr_nodes The number of MPI ranks.
* @param nodeID The MPI rank of this node.
* @param policy The queuing policy to use.
* @param timeBegin Time at the begininning of the simulation.
* @param timeEnd Time at the end of the simulation.
* @param dt_min Minimal allowed timestep (unsed with fixdt policy)
* @param dt_max Maximal allowed timestep
* @param verbose Is this #engine talkative ?
*/
void engine_init(struct engine *e, struct space *s, float dt, int nr_threads,
int nr_queues, int nr_nodes, int nodeID, int policy,
float timeBegin, float timeEnd, float dt_min, float dt_max,
int verbose) {
/* Store the values. */
e->s = s;
e->nr_threads = nr_threads;
e->policy = policy;
e->step = 0;
e->nullstep = 0;
e->nr_nodes = nr_nodes;
e->nodeID = nodeID;
e->proxy_ind = NULL;
e->nr_proxies = 0;
e->forcerebuild = 1;
e->forcerepart = REPART_NONE;
e->links = NULL;
e->nr_links = 0;
e->timeBegin = timeBegin;
e->timeEnd = timeEnd;
e->timeOld = timeBegin;
e->time = timeBegin;
e->ti_old = 0;
e->ti_current = 0;
e->timeStep = 0.;
e->dt_min = dt_min;
e->dt_max = dt_max;
e->file_stats = NULL;
e->verbose = verbose;
e->wallclock_time = 0.f;
engine_rank = nodeID;
/* Make the space link back to the engine. */
s->e = e;
#if defined(HAVE_SETAFFINITY)
const int nr_cores = sysconf(_SC_NPROCESSORS_ONLN);
int cpuid[nr_cores];
cpu_set_t cpuset;
if ((policy & engine_policy_cputight) == engine_policy_cputight) {
for (int k = 0; k < nr_cores; k++) cpuid[k] = k;
} else {
/* Get next highest power of 2. */
int maxint = 1;
while (maxint < nr_cores) maxint *= 2;
cpuid[0] = 0;
int k = 1;
for (int i = 1; i < maxint; i *= 2)
for (int j = maxint / i / 2; j < maxint; j += maxint / i)
if (j < nr_cores && j != 0) cpuid[k++] = j;
#if defined(HAVE_LIBNUMA) && defined(_GNU_SOURCE)
/* Ascending NUMA distance. Bubblesort(!) for stable equidistant CPUs. */
if (numa_available() >= 0) {
if (nodeID == 0) message("prefer NUMA-local CPUs");
const int home = numa_node_of_cpu(sched_getcpu());
const int half = nr_cores / 2;
const bool swap_hyperthreads = hyperthreads_present();
bool done = false;
if (swap_hyperthreads && nodeID == 0)
message("prefer physical cores to hyperthreads");
while (!done) {
done = true;
for (int i = 1; i < nr_cores; i++) {
const int node_a = numa_node_of_cpu(cpuid[i - 1]); const int node_b = numa_node_of_cpu(cpuid[i]);
/* Avoid using local hyperthreads over unused remote physical cores.
* Assume two hyperthreads, and that cpuid >= half partitions them.
*/
const int thread_a = swap_hyperthreads && cpuid[i - 1] >= half;
const int thread_b = swap_hyperthreads && cpuid[i] >= half;
bool swap = thread_a > thread_b;
if (thread_a == thread_b)
swap = numa_distance(home, node_a) > numa_distance(home, node_b);
if (swap) {
const int t = cpuid[i - 1];
cpuid[i - 1] = cpuid[i];
cpuid[i] = t;
done = false;
}
}
}
}
#endif
if (nodeID == 0) {
#ifdef WITH_MPI
printf("[%04i] %s engine_init: cpu map is [ ", nodeID,
clocks_get_timesincestart());
#else
printf("%s engine_init: cpu map is [ ", clocks_get_timesincestart());
#endif
for (int i = 0; i < nr_cores; i++) printf("%i ", cpuid[i]);
printf("].\n");
}
}
#endif
/* Are we doing stuff in parallel? */
if (nr_nodes > 1) {
#ifndef WITH_MPI
error("SWIFT was not compiled with MPI support.");
#else
e->policy |= engine_policy_mpi;
if ((e->proxies = (struct proxy *)malloc(sizeof(struct proxy) *
engine_maxproxies)) == NULL)
error("Failed to allocate memory for proxies.");
bzero(e->proxies, sizeof(struct proxy) * engine_maxproxies);
e->nr_proxies = 0;
#endif
}
/* Open some files */
if (e->nodeID == 0) {
e->file_stats = fopen("energy.txt", "w");
fprintf(e->file_stats,
"# Step Time E_kin E_int E_pot E_tot "
"p_x p_y p_z ang_x ang_y ang_z\n");
}
/* Print policy */
engine_print_policy(e);
/* Print information about the hydro scheme */
if (e->nodeID == 0) message("Hydrodynamic scheme: %s", SPH_IMPLEMENTATION);
/* Check we have sensible time bounds */
if (timeBegin >= timeEnd)
error(
"Final simulation time (t_end = %e) must be larger than the start time "
"(t_beg = %e)",
timeEnd, timeBegin);
/* Check we have sensible time step bounds */
if (e->dt_min > e->dt_max)
error(
"Minimal time step size must be smaller than maximal time step size ");
/* Deal with timestep */
e->timeBase = (timeEnd - timeBegin) / max_nr_timesteps;
e->ti_current = 0;
/* Fixed time-step case */
if ((e->policy & engine_policy_fixdt) == engine_policy_fixdt) {
e->dt_min = e->dt_max;
/* Find timestep on the timeline */
int dti_timeline = max_nr_timesteps;
while (e->dt_min < dti_timeline * e->timeBase) dti_timeline /= 2;
e->dt_min = e->dt_max = dti_timeline * e->timeBase;
if (e->nodeID == 0) message("Timestep set to %e", e->dt_max);
} else {
if (e->nodeID == 0) {
message("Absolute minimal timestep size: %e", e->timeBase);
float dt_min = timeEnd - timeBegin;
while (dt_min > e->dt_min) dt_min /= 2.f;
message("Minimal timestep size (on time-line): %e", dt_min);
float dt_max = timeEnd - timeBegin;
while (dt_max > e->dt_max) dt_max /= 2.f;
message("Maximal timestep size (on time-line): %e", dt_max);
}
}
if (e->dt_min < e->timeBase && e->nodeID == 0)
error(
"Minimal time-step size smaller than the absolute possible minimum "
"dt=%e",
e->timeBase);
if (e->dt_max > (e->timeEnd - e->timeBegin) && e->nodeID == 0)
error("Maximal time-step size larger than the simulation run time t=%e",
e->timeEnd - e->timeBegin);
/* Construct types for MPI communications */
#ifdef WITH_MPI
part_create_mpi_type(&e->part_mpi_type);
xpart_create_mpi_type(&e->xpart_mpi_type);
gpart_create_mpi_type(&e->gpart_mpi_type);
#endif
/* First of all, init the barrier and lock it. */
if (pthread_mutex_init(&e->barrier_mutex, NULL) != 0)
error("Failed to initialize barrier mutex.");
if (pthread_cond_init(&e->barrier_cond, NULL) != 0)
error("Failed to initialize barrier condition variable.");
if (pthread_mutex_lock(&e->barrier_mutex) != 0)
error("Failed to lock barrier mutex.");
e->barrier_running = 0;
e->barrier_launch = 0;
e->barrier_launchcount = 0;
/* Init the scheduler with enough tasks for the initial sorting tasks. */
int nr_tasks = 2 * s->tot_cells + e->nr_threads;
scheduler_init(&e->sched, e->s, nr_tasks, nr_queues, scheduler_flag_steal,
e->nodeID); s->nr_queues = nr_queues;
/* Create the sorting tasks. */
for (int i = 0; i < e->nr_threads; i++)
scheduler_addtask(&e->sched, task_type_psort, task_subtype_none, i, 0, NULL,
NULL, 0);
scheduler_ranktasks(&e->sched);
/* Allocate and init the threads. */
if ((e->runners =
(struct runner *)malloc(sizeof(struct runner) * nr_threads)) == NULL)
error("Failed to allocate threads array.");
for (int k = 0; k < nr_threads; k++) {
e->runners[k].id = k;
e->runners[k].e = e;
e->barrier_running += 1;
if (pthread_create(&e->runners[k].thread, NULL, &runner_main,
&e->runners[k]) != 0)
error("Failed to create runner thread.");
if ((e->policy & engine_policy_setaffinity) == engine_policy_setaffinity) {
#if defined(HAVE_SETAFFINITY)
/* Set a reasonable queue ID. */
e->runners[k].cpuid = cpuid[k % nr_cores];
if (nr_queues < nr_threads)
e->runners[k].qid = cpuid[k % nr_cores] * nr_queues / nr_cores;
else
e->runners[k].qid = k;
/* Set the cpu mask to zero | e->id. */
CPU_ZERO(&cpuset);
CPU_SET(cpuid[k % nr_cores], &cpuset);
/* Apply this mask to the runner's pthread. */
if (pthread_setaffinity_np(e->runners[k].thread, sizeof(cpu_set_t),
&cpuset) != 0)
error("Failed to set thread affinity.");
#else
error("SWIFT was not compiled with affinity enabled.");
#endif
} else {
e->runners[k].cpuid = k;
e->runners[k].qid = k * nr_queues / nr_threads;
}
// message( "runner %i on cpuid=%i with qid=%i." , e->runners[k].id ,
// e->runners[k].cpuid , e->runners[k].qid );
}
/* Wait for the runner threads to be in place. */
while (e->barrier_running || e->barrier_launch)
if (pthread_cond_wait(&e->barrier_cond, &e->barrier_mutex) != 0)
error("Error while waiting for runner threads to get in place.");
}
/**
* @brief Prints the current policy of an engine
*
* @param e The engine to print information about
*/
void engine_print_policy(struct engine *e) {
#ifdef WITH_MPI
if (e->nodeID == 0) {
printf("[0000] %s engine_policy: engine policies are [ ",
clocks_get_timesincestart());
for (int k = 1; k < 32; k++)
if (e->policy & (1 << k)) printf(" %s ", engine_policy_names[k + 1]);
printf(" ]\n"); fflush(stdout);
}
#else
printf("%s engine_policy: engine policies are [ ",
clocks_get_timesincestart());
for (int k = 1; k < 32; k++)
if (e->policy & (1 << k)) printf(" %s ", engine_policy_names[k + 1]);
printf(" ]\n");
fflush(stdout);
#endif
}