|
Check-in Number:
|
4738 | |
| Date: |
2004-Oct-08 18:17:02 (local)
2004-Oct-08 16:17:02 (UTC) |
| User: | rse |
| Branch: | |
| Comment: |
Added PTH_CTRL_FAVOURNEW control which allows the user
to disable the favouring of new threads on scheduling
to get more strict priority based scheduling behavior.
Triggered by: Vinu V <Vinu_V@mindtree.com> |
| Tickets: |
|
| Inspections: |
|
| Files: |
|
ossp-pkg/pth/ChangeLog 1.625 -> 1.626
--- ChangeLog 2004/09/25 21:14:44 1.625
+++ ChangeLog 2004/10/08 16:17:02 1.626
@@ -21,6 +21,11 @@
Changes between 2.0.2 and 2.0.3 (12-Sep-2004 to xx-xxx-2004)
+ *) Added PTH_CTRL_FAVOURNEW control which allows the user
+ to disable the favouring of new threads on scheduling
+ to get more strict priority based scheduling behavior.
+ [Ralf S. Engelschall, Vinu V <Vinu_V@mindtree.com>]
+
*) Upgraded build environment to GNU libtool 1.5.10
[Ralf S. Engelschall]
|
|
ossp-pkg/pth/THANKS 1.96 -> 1.97
--- THANKS 2004/09/12 11:45:09 1.96
+++ THANKS 2004/10/08 16:17:02 1.97
@@ -107,6 +107,7 @@
o David Scott Urban <urban@ast.lmco.com>
o Laurent Vaucher <laurent.vaucher@ficsgrp.com>
o Martin Vernard <vernard@cc.gatech.edu>
+ o Vinu V <Vinu_V@mindtree.com>
o Olaf Wasmuth <olaf.wasmuth@europe.eds.com>
o Chia-Hsing Yu <davidyu@oio.cx>
|
|
ossp-pkg/pth/pth.h.in 1.142 -> 1.143
--- pth.h.in 2004/09/12 11:36:13 1.142
+++ pth.h.in 2004/10/08 16:17:02 1.143
@@ -124,6 +124,7 @@
PTH_CTRL_GETTHREADS_SUSPENDED|\
PTH_CTRL_GETTHREADS_DEAD)
#define PTH_CTRL_DUMPSTATE _BIT(10)
+#define PTH_CTRL_FAVOURNEW _BIT(11)
/* the time value structure */
typedef struct timeval pth_time_t;
|
|
ossp-pkg/pth/pth.pod 1.163 -> 1.164
--- pth.pod 2004/07/13 10:50:49 1.163
+++ pth.pod 2004/10/08 16:17:02 1.164
@@ -679,6 +679,15 @@
of the internal B<Pth> library state is written to. The main information
which is currently written out is the current state of the thread pool.
+=item C<PTH_CTRL_FAVOURNEW>
+
+This requires a second argument of type `C<int>' which specified whether
+the B<GNU Pth> scheduler favours new threads on startup, i.e., whether
+they are moved from the new queue to the top (argument is C<TRUE>) or
+middle (argument is C<FALSE>) of the ready queue. The default is to
+favour new threads to make sure they do not starve already at startup,
+although this slightly violates the strict priority based scheduling.
+
=back
The function returns C<-1> on error.
|
|
ossp-pkg/pth/pth_lib.c 1.57 -> 1.58
--- pth_lib.c 2004/07/13 10:50:49 1.57
+++ pth_lib.c 2004/10/08 16:17:02 1.58
@@ -193,6 +193,10 @@
FILE *fp = va_arg(ap, FILE *);
pth_dumpstate(fp);
}
+ else if (query & PTH_CTRL_FAVOURNEW) {
+ int favournew = va_arg(ap, int);
+ pth_favournew = (favournew ? 1 : 0);
+ }
else
rc = -1;
va_end(ap);
|
|
ossp-pkg/pth/pth_sched.c 1.91 -> 1.92
--- pth_sched.c 2004/07/13 10:50:49 1.91
+++ pth_sched.c 2004/10/08 16:17:02 1.92
@@ -35,6 +35,7 @@
intern pth_pqueue_t pth_WQ; /* queue of threads waiting for an event */
intern pth_pqueue_t pth_SQ; /* queue of suspended threads */
intern pth_pqueue_t pth_DQ; /* queue of terminated threads */
+intern int pth_favournew; /* favour new threads on startup */
intern float pth_loadval; /* average scheduler load value */
static int pth_sigpipe[2]; /* internal signal occurrence pipe */
@@ -68,6 +69,9 @@
pth_pqueue_init(&pth_SQ);
pth_pqueue_init(&pth_DQ);
+ /* initialize scheduling hints */
+ pth_favournew = 1; /* the default is the original behaviour */
+
/* initialize load support */
pth_loadval = 1.0;
pth_time_set(&pth_loadticknext, PTH_TIME_NOW);
@@ -179,13 +183,16 @@
*/
for (;;) {
/*
- * Move threads from new queue to ready queue and give
- * them maximum priority so they start immediately
+ * Move threads from new queue to ready queue and optionally
+ * give them maximum priority so they start immediately.
*/
while ((t = pth_pqueue_tail(&pth_NQ)) != NULL) {
pth_pqueue_delete(&pth_NQ, t);
t->state = PTH_STATE_READY;
- pth_pqueue_insert(&pth_RQ, pth_pqueue_favorite_prio(&pth_RQ), t);
+ if (pth_favournew)
+ pth_pqueue_insert(&pth_RQ, pth_pqueue_favorite_prio(&pth_RQ), t);
+ else
+ pth_pqueue_insert(&pth_RQ, PTH_PRIO_STD, t);
pth_debug2("pth_scheduler: new thread \"%s\" moved to top of ready queue", t->name);
}
|
|
