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-rw-r--r--erts/doc/src/erl.xml11
-rw-r--r--erts/emulator/beam/erl_init.c16
-rw-r--r--erts/emulator/beam/erl_process.c255
-rw-r--r--erts/emulator/beam/erl_process.h3
-rw-r--r--erts/etc/common/erlexec.c1
5 files changed, 244 insertions, 42 deletions
diff --git a/erts/doc/src/erl.xml b/erts/doc/src/erl.xml
index 0df16a551c..72cbf1f3b2 100644
--- a/erts/doc/src/erl.xml
+++ b/erts/doc/src/erl.xml
@@ -911,6 +911,17 @@
<p>For more information, see
<seealso marker="erlang#system_info_cpu_topology">erlang:system_info(cpu_topology)</seealso>.</p>
</item>
+ <tag><marker id="+sws"><c>+sws default|legacy|proposal</c></marker></tag>
+ <item>
+ <p>Set scheduler wakeup strategy. Default is <c>legacy</c> (has been
+ used since OTP-R13B). The <c>proposal</c> strategy is the currently
+ proposed strategy for OTP-R16. Note that the <c>proposal</c> strategy
+ might change during OTP-R15.
+ </p>
+ <p><em>NOTE:</em> This flag may be removed or changed at any time
+ without prior notice.
+ </p>
+ </item>
<tag><marker id="+swt"><c>+swt very_low|low|medium|high|very_high</c></marker></tag>
<item>
<p>Set scheduler wakeup threshold. Default is <c>medium</c>.
diff --git a/erts/emulator/beam/erl_init.c b/erts/emulator/beam/erl_init.c
index 5236f41c8f..8bcba9de15 100644
--- a/erts/emulator/beam/erl_init.c
+++ b/erts/emulator/beam/erl_init.c
@@ -517,6 +517,8 @@ void erts_usage(void)
erts_fprintf(stderr, " see the erl(1) documentation for more info.\n");
erts_fprintf(stderr, "-sct cput set cpu topology,\n");
erts_fprintf(stderr, " see the erl(1) documentation for more info.\n");
+ erts_fprintf(stderr, "-sws val set scheduler wakeup strategy, valid values are:\n");
+ erts_fprintf(stderr, " default|legacy|proposal.\n");
erts_fprintf(stderr, "-swt val set scheduler wakeup threshold, valid values are:\n");
erts_fprintf(stderr, " very_low|low|medium|high|very_high.\n");
erts_fprintf(stderr, "-sss size suggested stack size in kilo words for scheduler threads,\n");
@@ -1270,13 +1272,23 @@ erl_start(int argc, char **argv)
erts_use_sender_punish = 0;
else if (sys_strcmp("wt", sub_param) == 0) {
arg = get_arg(sub_param+2, argv[i+1], &i);
- if (erts_sched_set_wakeup_limit(arg) != 0) {
+ if (erts_sched_set_wakeup_other_thresold(arg) != 0) {
erts_fprintf(stderr, "scheduler wakeup threshold: %s\n",
arg);
erts_usage();
}
VERBOSE(DEBUG_SYSTEM,
- ("scheduler wakup threshold: %s\n", arg));
+ ("scheduler wakeup threshold: %s\n", arg));
+ }
+ else if (sys_strcmp("ws", sub_param) == 0) {
+ arg = get_arg(sub_param+2, argv[i+1], &i);
+ if (erts_sched_set_wakeup_other_type(arg) != 0) {
+ erts_fprintf(stderr, "scheduler wakeup strategy: %s\n",
+ arg);
+ erts_usage();
+ }
+ VERBOSE(DEBUG_SYSTEM,
+ ("scheduler wakeup threshold: %s\n", arg));
}
else if (has_prefix("ss", sub_param)) {
/* suggested stack size (Kilo Words) for scheduler threads */
diff --git a/erts/emulator/beam/erl_process.c b/erts/emulator/beam/erl_process.c
index 651e48da46..09ca536188 100644
--- a/erts/emulator/beam/erl_process.c
+++ b/erts/emulator/beam/erl_process.c
@@ -68,15 +68,6 @@
#define ERTS_SCHED_TSE_SLEEP_SPINCOUNT_FACT 1000
#define ERTS_SCHED_SUSPEND_SLEEP_SPINCOUNT 0
-#define ERTS_WAKEUP_OTHER_LIMIT_VERY_HIGH (200*CONTEXT_REDS)
-#define ERTS_WAKEUP_OTHER_LIMIT_HIGH (50*CONTEXT_REDS)
-#define ERTS_WAKEUP_OTHER_LIMIT_MEDIUM (10*CONTEXT_REDS)
-#define ERTS_WAKEUP_OTHER_LIMIT_LOW (CONTEXT_REDS)
-#define ERTS_WAKEUP_OTHER_LIMIT_VERY_LOW (CONTEXT_REDS/10)
-
-#define ERTS_WAKEUP_OTHER_DEC 10
-#define ERTS_WAKEUP_OTHER_FIXED_INC (CONTEXT_REDS/10)
-
#if 0 || defined(DEBUG)
#define ERTS_FAKE_SCHED_BIND_PRINT_SORTED_CPU_DATA
#endif
@@ -133,8 +124,6 @@ Uint erts_no_schedulers;
Uint erts_max_processes = ERTS_DEFAULT_MAX_PROCESSES;
Uint erts_process_tab_index_mask;
-static int wakeup_other_limit;
-
int erts_sched_thread_suggested_stack_size = -1;
#ifdef ERTS_ENABLE_LOCK_CHECK
@@ -3578,12 +3567,192 @@ erts_debug_nbalance(void)
#endif
}
+/* Wakeup other schedulers */
+
+typedef enum {
+ ERTS_SCHED_WAKEUP_OTHER_THRESHOLD_VERY_HIGH,
+ ERTS_SCHED_WAKEUP_OTHER_THRESHOLD_HIGH,
+ ERTS_SCHED_WAKEUP_OTHER_THRESHOLD_MEDIUM,
+ ERTS_SCHED_WAKEUP_OTHER_THRESHOLD_LOW,
+ ERTS_SCHED_WAKEUP_OTHER_THRESHOLD_VERY_LOW
+} ErtsSchedWakeupOtherThreshold;
+
+typedef enum {
+ ERTS_SCHED_WAKEUP_OTHER_TYPE_PROPOSAL,
+ ERTS_SCHED_WAKEUP_OTHER_TYPE_LEGACY
+} ErtsSchedWakeupOtherType;
+
+/* First proposal */
+
+#define ERTS_WAKEUP_OTHER_LIMIT_VERY_HIGH (200*CONTEXT_REDS)
+#define ERTS_WAKEUP_OTHER_LIMIT_HIGH (50*CONTEXT_REDS)
+#define ERTS_WAKEUP_OTHER_LIMIT_MEDIUM (10*CONTEXT_REDS)
+#define ERTS_WAKEUP_OTHER_LIMIT_LOW (CONTEXT_REDS)
+#define ERTS_WAKEUP_OTHER_LIMIT_VERY_LOW (CONTEXT_REDS/10)
+
+#define ERTS_WAKEUP_OTHER_DEC_SHIFT_VERY_HIGH 3
+#define ERTS_WAKEUP_OTHER_DEC_SHIFT_HIGH 1
+#define ERTS_WAKEUP_OTHER_DEC_SHIFT_MEDIUM 0
+#define ERTS_WAKEUP_OTHER_DEC_SHIFT_LOW -2
+#define ERTS_WAKEUP_OTHER_DEC_SHIFT_VERY_LOW -5
+
+#define ERTS_WAKEUP_OTHER_DEC_SHIFT 2
+#define ERTS_WAKEUP_OTHER_FIXED_INC (CONTEXT_REDS/10)
+
+/* To be legacy */
+
+#define ERTS_WAKEUP_OTHER_LIMIT_VERY_HIGH_LEGACY (200*CONTEXT_REDS)
+#define ERTS_WAKEUP_OTHER_LIMIT_HIGH_LEGACY (50*CONTEXT_REDS)
+#define ERTS_WAKEUP_OTHER_LIMIT_MEDIUM_LEGACY (10*CONTEXT_REDS)
+#define ERTS_WAKEUP_OTHER_LIMIT_LOW_LEGACY (CONTEXT_REDS)
+#define ERTS_WAKEUP_OTHER_LIMIT_VERY_LOW_LEGACY (CONTEXT_REDS/10)
+
+#define ERTS_WAKEUP_OTHER_DEC_LEGACY 10
+#define ERTS_WAKEUP_OTHER_FIXED_INC_LEGACY (CONTEXT_REDS/10)
+
+#ifdef ERTS_SMP
+
+static struct {
+ ErtsSchedWakeupOtherThreshold threshold;
+ ErtsSchedWakeupOtherType type;
+ int limit;
+ int dec_shift;
+ int dec_mask;
+ void (*check)(ErtsRunQueue *rq);
+} wakeup_other;
+
+static void
+wakeup_other_check(ErtsRunQueue *rq)
+{
+ int wo_reds = rq->wakeup_other_reds;
+ if (wo_reds) {
+ int left_len = rq->len - 1;
+ if (left_len < 1) {
+ int wo_reduce = wo_reds << wakeup_other.dec_shift;
+ wo_reduce &= wakeup_other.dec_mask;
+ rq->wakeup_other -= wo_reduce;
+ if (rq->wakeup_other < 0)
+ rq->wakeup_other = 0;
+ }
+ else {
+ rq->wakeup_other += (left_len*wo_reds
+ + ERTS_WAKEUP_OTHER_FIXED_INC);
+ if (rq->wakeup_other > wakeup_other.limit) {
+ int empty_rqs =
+ erts_smp_atomic32_read_acqb(&no_empty_run_queues);
+ if (empty_rqs != 0)
+ wake_scheduler_on_empty_runq(rq);
+ rq->wakeup_other = 0;
+ }
+ }
+ rq->wakeup_other_reds = 0;
+ }
+}
+
+static void
+wakeup_other_set_limit(void)
+{
+ switch (wakeup_other.threshold) {
+ case ERTS_SCHED_WAKEUP_OTHER_THRESHOLD_VERY_HIGH:
+ wakeup_other.limit = ERTS_WAKEUP_OTHER_LIMIT_VERY_HIGH;
+ wakeup_other.dec_shift = ERTS_WAKEUP_OTHER_DEC_SHIFT_VERY_HIGH;
+ break;
+ case ERTS_SCHED_WAKEUP_OTHER_THRESHOLD_HIGH:
+ wakeup_other.limit = ERTS_WAKEUP_OTHER_LIMIT_HIGH;
+ wakeup_other.dec_shift = ERTS_WAKEUP_OTHER_DEC_SHIFT_HIGH;
+ break;
+ case ERTS_SCHED_WAKEUP_OTHER_THRESHOLD_MEDIUM:
+ wakeup_other.limit = ERTS_WAKEUP_OTHER_LIMIT_MEDIUM;
+ wakeup_other.dec_shift = ERTS_WAKEUP_OTHER_DEC_SHIFT_MEDIUM;
+ break;
+ case ERTS_SCHED_WAKEUP_OTHER_THRESHOLD_LOW:
+ wakeup_other.limit = ERTS_WAKEUP_OTHER_LIMIT_LOW;
+ wakeup_other.dec_shift = ERTS_WAKEUP_OTHER_DEC_SHIFT_LOW;
+ break;
+ case ERTS_SCHED_WAKEUP_OTHER_THRESHOLD_VERY_LOW:
+ wakeup_other.limit = ERTS_WAKEUP_OTHER_LIMIT_VERY_LOW;
+ wakeup_other.dec_shift = ERTS_WAKEUP_OTHER_DEC_SHIFT_VERY_LOW;
+ break;
+ }
+ if (wakeup_other.dec_shift < 0)
+ wakeup_other.dec_mask = (1 << (sizeof(wakeup_other.dec_mask)*8
+ + wakeup_other.dec_shift)) - 1;
+ else {
+ wakeup_other.dec_mask = 0;
+ wakeup_other.dec_mask = ~wakeup_other.dec_mask;
+ }
+}
+
+static void
+wakeup_other_check_legacy(ErtsRunQueue *rq)
+{
+ int wo_reds = rq->wakeup_other_reds;
+ if (wo_reds) {
+ if (rq->len < 2) {
+ rq->wakeup_other -= ERTS_WAKEUP_OTHER_DEC_LEGACY*wo_reds;
+ if (rq->wakeup_other < 0)
+ rq->wakeup_other = 0;
+ }
+ else if (rq->wakeup_other < wakeup_other.limit)
+ rq->wakeup_other += rq->len*wo_reds + ERTS_WAKEUP_OTHER_FIXED_INC_LEGACY;
+ else {
+ if (erts_smp_atomic32_read_acqb(&no_empty_run_queues) != 0) {
+ wake_scheduler_on_empty_runq(rq);
+ rq->wakeup_other = 0;
+ }
+ rq->wakeup_other = 0;
+ }
+ }
+ rq->wakeup_other_reds = 0;
+}
+
+static void
+wakeup_other_set_limit_legacy(void)
+{
+ switch (wakeup_other.threshold) {
+ case ERTS_SCHED_WAKEUP_OTHER_THRESHOLD_VERY_HIGH:
+ wakeup_other.limit = ERTS_WAKEUP_OTHER_LIMIT_VERY_HIGH_LEGACY;
+ break;
+ case ERTS_SCHED_WAKEUP_OTHER_THRESHOLD_HIGH:
+ wakeup_other.limit = ERTS_WAKEUP_OTHER_LIMIT_HIGH_LEGACY;
+ break;
+ case ERTS_SCHED_WAKEUP_OTHER_THRESHOLD_MEDIUM:
+ wakeup_other.limit = ERTS_WAKEUP_OTHER_LIMIT_MEDIUM_LEGACY;
+ break;
+ case ERTS_SCHED_WAKEUP_OTHER_THRESHOLD_LOW:
+ wakeup_other.limit = ERTS_WAKEUP_OTHER_LIMIT_LOW_LEGACY;
+ break;
+ case ERTS_SCHED_WAKEUP_OTHER_THRESHOLD_VERY_LOW:
+ wakeup_other.limit = ERTS_WAKEUP_OTHER_LIMIT_VERY_LOW_LEGACY;
+ break;
+ }
+}
+
+static void
+set_wakeup_other_data(void)
+{
+ switch (wakeup_other.type) {
+ case ERTS_SCHED_WAKEUP_OTHER_TYPE_PROPOSAL:
+ wakeup_other.check = wakeup_other_check;
+ wakeup_other_set_limit();
+ break;
+ case ERTS_SCHED_WAKEUP_OTHER_TYPE_LEGACY:
+ wakeup_other.check = wakeup_other_check_legacy;
+ wakeup_other_set_limit_legacy();
+ break;
+ }
+}
+
+#endif
+
void
erts_early_init_scheduling(int no_schedulers)
{
aux_work_timeout_early_init(no_schedulers);
- wakeup_other_limit = ERTS_WAKEUP_OTHER_LIMIT_MEDIUM;
-
+#ifdef ERTS_SMP
+ wakeup_other.threshold = ERTS_SCHED_WAKEUP_OTHER_THRESHOLD_MEDIUM;
+ wakeup_other.type = ERTS_SCHED_WAKEUP_OTHER_TYPE_LEGACY;
+#endif
sched_busy_wait.sys_schedule = ERTS_SCHED_SYS_SLEEP_SPINCOUNT_MEDIUM;
sched_busy_wait.tse = (ERTS_SCHED_SYS_SLEEP_SPINCOUNT_MEDIUM
* ERTS_SCHED_TSE_SLEEP_SPINCOUNT_FACT);
@@ -3592,20 +3761,43 @@ erts_early_init_scheduling(int no_schedulers)
}
int
-erts_sched_set_wakeup_limit(char *str)
+erts_sched_set_wakeup_other_thresold(char *str)
{
+ ErtsSchedWakeupOtherThreshold threshold;
if (sys_strcmp(str, "very_high") == 0)
- wakeup_other_limit = ERTS_WAKEUP_OTHER_LIMIT_VERY_HIGH;
+ threshold = ERTS_SCHED_WAKEUP_OTHER_THRESHOLD_VERY_HIGH;
else if (sys_strcmp(str, "high") == 0)
- wakeup_other_limit = ERTS_WAKEUP_OTHER_LIMIT_HIGH;
+ threshold = ERTS_SCHED_WAKEUP_OTHER_THRESHOLD_HIGH;
else if (sys_strcmp(str, "medium") == 0)
- wakeup_other_limit = ERTS_WAKEUP_OTHER_LIMIT_MEDIUM;
+ threshold = ERTS_SCHED_WAKEUP_OTHER_THRESHOLD_MEDIUM;
else if (sys_strcmp(str, "low") == 0)
- wakeup_other_limit = ERTS_WAKEUP_OTHER_LIMIT_LOW;
+ threshold = ERTS_SCHED_WAKEUP_OTHER_THRESHOLD_LOW;
else if (sys_strcmp(str, "very_low") == 0)
- wakeup_other_limit = ERTS_WAKEUP_OTHER_LIMIT_VERY_LOW;
+ threshold = ERTS_SCHED_WAKEUP_OTHER_THRESHOLD_VERY_LOW;
+ else
+ return EINVAL;
+#ifdef ERTS_SMP
+ wakeup_other.threshold = threshold;
+ set_wakeup_other_data();
+#endif
+ return 0;
+}
+
+int
+erts_sched_set_wakeup_other_type(char *str)
+{
+ ErtsSchedWakeupOtherType type;
+ if (sys_strcmp(str, "proposal") == 0)
+ type = ERTS_SCHED_WAKEUP_OTHER_TYPE_PROPOSAL;
+ else if (sys_strcmp(str, "default") == 0)
+ type = ERTS_SCHED_WAKEUP_OTHER_TYPE_LEGACY;
+ else if (sys_strcmp(str, "legacy") == 0)
+ type = ERTS_SCHED_WAKEUP_OTHER_TYPE_LEGACY;
else
return EINVAL;
+#ifdef ERTS_SMP
+ wakeup_other.type = type;
+#endif
return 0;
}
@@ -3677,6 +3869,10 @@ erts_init_scheduling(int no_schedulers, int no_schedulers_online)
init_misc_op_list_alloc();
+#ifdef ERTS_SMP
+ set_wakeup_other_data();
+#endif
+
ASSERT(no_schedulers_online <= no_schedulers);
ASSERT(no_schedulers_online >= 1);
ASSERT(no_schedulers >= 1);
@@ -6566,26 +6762,7 @@ Process *schedule(Process *p, int calls)
exec_misc_ops(rq);
#ifdef ERTS_SMP
- {
- int wo_reds = rq->wakeup_other_reds;
- if (wo_reds) {
- if (rq->len < 2) {
- rq->wakeup_other -= ERTS_WAKEUP_OTHER_DEC*wo_reds;
- if (rq->wakeup_other < 0)
- rq->wakeup_other = 0;
- }
- else if (rq->wakeup_other < wakeup_other_limit)
- rq->wakeup_other += rq->len*wo_reds + ERTS_WAKEUP_OTHER_FIXED_INC;
- else {
- if (erts_smp_atomic32_read_acqb(&no_empty_run_queues) != 0) {
- wake_scheduler_on_empty_runq(rq);
- rq->wakeup_other = 0;
- }
- rq->wakeup_other = 0;
- }
- }
- rq->wakeup_other_reds = 0;
- }
+ wakeup_other.check(rq);
#endif
/*
diff --git a/erts/emulator/beam/erl_process.h b/erts/emulator/beam/erl_process.h
index 92ff99db6e..2683b8540d 100644
--- a/erts/emulator/beam/erl_process.h
+++ b/erts/emulator/beam/erl_process.h
@@ -1096,7 +1096,8 @@ ErtsProcList *erts_proclist_create(Process *);
void erts_proclist_destroy(ErtsProcList *);
int erts_proclist_same(ErtsProcList *, Process *);
-int erts_sched_set_wakeup_limit(char *str);
+int erts_sched_set_wakeup_other_thresold(char *str);
+int erts_sched_set_wakeup_other_type(char *str);
int erts_sched_set_busy_wait_threshold(char *str);
#if defined(ERTS_SMP) && defined(ERTS_ENABLE_LOCK_CHECK)
diff --git a/erts/etc/common/erlexec.c b/erts/etc/common/erlexec.c
index a49d10d6f3..c9aee16def 100644
--- a/erts/etc/common/erlexec.c
+++ b/erts/etc/common/erlexec.c
@@ -125,6 +125,7 @@ static char *pluss_val_switches[] = {
"cl",
"ct",
"wt",
+ "ws",
"ss",
NULL
};
generated by cgit v1.2.3 (git 2.25.1) at 2024-11-20 15:37:40 +0000