From 447eecd1af7ba3e3a46098d93b88964c0f71ca41 Mon Sep 17 00:00:00 2001 From: Rickard Green Date: Tue, 3 Apr 2012 19:53:52 +0200 Subject: Add switch controlling scheduler busy wait --- erts/doc/src/erl.xml | 10 ++++++ erts/emulator/beam/erl_init.c | 12 +++++++ erts/emulator/beam/erl_process.c | 76 ++++++++++++++++++++++++++++++++++++---- erts/emulator/beam/erl_process.h | 1 + erts/etc/common/erlexec.c | 1 + 5 files changed, 94 insertions(+), 6 deletions(-) diff --git a/erts/doc/src/erl.xml b/erts/doc/src/erl.xml index cfbc38f176..0df16a551c 100644 --- a/erts/doc/src/erl.xml +++ b/erts/doc/src/erl.xml @@ -766,6 +766,16 @@ erlang:system_info(scheduler_bindings).

+ +sbwt none|very_short|short|medium|long|very_long + +

Set scheduler busy wait threshold. Default is medium. + The threshold determines how long schedulers should busy + wait when running out of work before going to sleep. +

+

NOTE: This flag may be removed or changed at any time + without prior notice. +

+ +scl true|false

Enable or disable scheduler compaction of load. By default diff --git a/erts/emulator/beam/erl_init.c b/erts/emulator/beam/erl_init.c index ca4385dd3a..5236f41c8f 100644 --- a/erts/emulator/beam/erl_init.c +++ b/erts/emulator/beam/erl_init.c @@ -511,6 +511,8 @@ void erts_usage(void) erts_fprintf(stderr, "-rg amount set reader groups limit\n"); erts_fprintf(stderr, "-sbt type set scheduler bind type, valid types are:\n"); erts_fprintf(stderr, " u|ns|ts|ps|s|nnts|nnps|tnnps|db\n"); + erts_fprintf(stderr, "-sbwt val set scheduler busy wait threshold, valid values are:\n"); + erts_fprintf(stderr, " none|very_short|short|medium|long|very_long.\n"); erts_fprintf(stderr, "-scl bool enable/disable compaction of scheduler load,\n"); erts_fprintf(stderr, " see the erl(1) documentation for more info.\n"); erts_fprintf(stderr, "-sct cput set cpu topology,\n"); @@ -1198,6 +1200,16 @@ erl_start(int argc, char **argv) erts_usage(); } } + else if (has_prefix("bwt", sub_param)) { + arg = get_arg(sub_param+3, argv[i+1], &i); + if (erts_sched_set_busy_wait_threshold(arg) != 0) { + erts_fprintf(stderr, "bad scheduler busy wait threshold: %s\n", + arg); + erts_usage(); + } + VERBOSE(DEBUG_SYSTEM, + ("scheduler wakup threshold: %s\n", arg)); + } else if (has_prefix("cl", sub_param)) { arg = get_arg(sub_param+2, argv[i+1], &i); if (sys_strcmp("true", arg) == 0) diff --git a/erts/emulator/beam/erl_process.c b/erts/emulator/beam/erl_process.c index 95d408f79d..651e48da46 100644 --- a/erts/emulator/beam/erl_process.c +++ b/erts/emulator/beam/erl_process.c @@ -52,10 +52,20 @@ #define ERTS_SCHED_SPIN_UNTIL_YIELD 100 -#define ERTS_SCHED_SYS_SLEEP_SPINCOUNT 10 +#define ERTS_SCHED_SYS_SLEEP_SPINCOUNT_VERY_LONG 40 +#define ERTS_SCHED_AUX_WORK_SLEEP_SPINCOUNT_FACT_VERY_LONG 1000 +#define ERTS_SCHED_SYS_SLEEP_SPINCOUNT_LONG 20 +#define ERTS_SCHED_AUX_WORK_SLEEP_SPINCOUNT_FACT_LONG 1000 +#define ERTS_SCHED_SYS_SLEEP_SPINCOUNT_MEDIUM 10 +#define ERTS_SCHED_AUX_WORK_SLEEP_SPINCOUNT_FACT_MEDIUM 1000 +#define ERTS_SCHED_SYS_SLEEP_SPINCOUNT_SHORT 10 +#define ERTS_SCHED_AUX_WORK_SLEEP_SPINCOUNT_FACT_SHORT 0 +#define ERTS_SCHED_SYS_SLEEP_SPINCOUNT_VERY_SHORT 5 +#define ERTS_SCHED_AUX_WORK_SLEEP_SPINCOUNT_FACT_VERY_SHORT 0 +#define ERTS_SCHED_SYS_SLEEP_SPINCOUNT_NONE 0 +#define ERTS_SCHED_AUX_WORK_SLEEP_SPINCOUNT_FACT_NONE 0 + #define ERTS_SCHED_TSE_SLEEP_SPINCOUNT_FACT 1000 -#define ERTS_SCHED_TSE_SLEEP_SPINCOUNT \ - (ERTS_SCHED_SYS_SLEEP_SPINCOUNT*ERTS_SCHED_TSE_SLEEP_SPINCOUNT_FACT) #define ERTS_SCHED_SUSPEND_SLEEP_SPINCOUNT 0 #define ERTS_WAKEUP_OTHER_LIMIT_VERY_HIGH (200*CONTEXT_REDS) @@ -131,6 +141,12 @@ int erts_sched_thread_suggested_stack_size = -1; ErtsLcPSDLocks erts_psd_required_locks[ERTS_PSD_SIZE]; #endif +static struct { + int aux_work; + int tse; + int sys_schedule; +} sched_busy_wait; + #ifdef ERTS_SMP int erts_disable_proc_not_running_opt; @@ -2046,7 +2062,7 @@ scheduler_wait(int *fcalls, ErtsSchedulerData *esdp, ErtsRunQueue *rq) erts_smp_runq_unlock(rq); - spincount = ERTS_SCHED_TSE_SLEEP_SPINCOUNT; + spincount = sched_busy_wait.tse; tse_wait: @@ -2097,7 +2113,7 @@ scheduler_wait(int *fcalls, ErtsSchedulerData *esdp, ErtsRunQueue *rq) } flgs = sched_prep_cont_spin_wait(ssi); - spincount = ERTS_SCHED_TSE_SLEEP_SPINCOUNT; + spincount = sched_busy_wait.aux_work; if (!(flgs & ERTS_SSI_FLG_WAITING)) { ASSERT(!(flgs & ERTS_SSI_FLG_SLEEPING)); @@ -2134,7 +2150,9 @@ scheduler_wait(int *fcalls, ErtsSchedulerData *esdp, ErtsRunQueue *rq) ASSERT(working); sched_wall_time_change(esdp, working = 0); - spincount = ERTS_SCHED_SYS_SLEEP_SPINCOUNT; + spincount = sched_busy_wait.sys_schedule; + if (spincount == 0) + goto sys_aux_work; while (spincount-- > 0) { @@ -3565,6 +3583,12 @@ erts_early_init_scheduling(int no_schedulers) { aux_work_timeout_early_init(no_schedulers); wakeup_other_limit = ERTS_WAKEUP_OTHER_LIMIT_MEDIUM; + + 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); + sched_busy_wait.aux_work = (ERTS_SCHED_SYS_SLEEP_SPINCOUNT_MEDIUM + * ERTS_SCHED_AUX_WORK_SLEEP_SPINCOUNT_FACT_MEDIUM); } int @@ -3585,6 +3609,46 @@ erts_sched_set_wakeup_limit(char *str) return 0; } +int +erts_sched_set_busy_wait_threshold(char *str) +{ + int sys_sched; + int aux_work_fact; + + if (sys_strcmp(str, "very_long") == 0) { + sys_sched = ERTS_SCHED_SYS_SLEEP_SPINCOUNT_VERY_LONG; + aux_work_fact = ERTS_SCHED_AUX_WORK_SLEEP_SPINCOUNT_FACT_VERY_LONG; + } + else if (sys_strcmp(str, "long") == 0) { + sys_sched = ERTS_SCHED_SYS_SLEEP_SPINCOUNT_LONG; + aux_work_fact = ERTS_SCHED_AUX_WORK_SLEEP_SPINCOUNT_FACT_LONG; + } + else if (sys_strcmp(str, "medium") == 0) { + sys_sched = ERTS_SCHED_SYS_SLEEP_SPINCOUNT_MEDIUM; + aux_work_fact = ERTS_SCHED_AUX_WORK_SLEEP_SPINCOUNT_FACT_MEDIUM; + } + else if (sys_strcmp(str, "short") == 0) { + sys_sched = ERTS_SCHED_SYS_SLEEP_SPINCOUNT_SHORT; + aux_work_fact = ERTS_SCHED_AUX_WORK_SLEEP_SPINCOUNT_FACT_SHORT; + } + else if (sys_strcmp(str, "very_short") == 0) { + sys_sched = ERTS_SCHED_SYS_SLEEP_SPINCOUNT_VERY_SHORT; + aux_work_fact = ERTS_SCHED_AUX_WORK_SLEEP_SPINCOUNT_FACT_VERY_SHORT; + } + else if (sys_strcmp(str, "none") == 0) { + sys_sched = ERTS_SCHED_SYS_SLEEP_SPINCOUNT_NONE; + aux_work_fact = ERTS_SCHED_AUX_WORK_SLEEP_SPINCOUNT_FACT_NONE; + } + else { + return EINVAL; + } + + sched_busy_wait.sys_schedule = sys_sched; + sched_busy_wait.tse = sys_sched*ERTS_SCHED_TSE_SLEEP_SPINCOUNT_FACT; + sched_busy_wait.aux_work = sys_sched*aux_work_fact; + + return 0; +} static void init_aux_work_data(ErtsAuxWorkData *awdp, ErtsSchedulerData *esdp) { diff --git a/erts/emulator/beam/erl_process.h b/erts/emulator/beam/erl_process.h index cff0783bc4..92ff99db6e 100644 --- a/erts/emulator/beam/erl_process.h +++ b/erts/emulator/beam/erl_process.h @@ -1097,6 +1097,7 @@ void erts_proclist_destroy(ErtsProcList *); int erts_proclist_same(ErtsProcList *, Process *); int erts_sched_set_wakeup_limit(char *str); +int erts_sched_set_busy_wait_threshold(char *str); #if defined(ERTS_SMP) && defined(ERTS_ENABLE_LOCK_CHECK) int erts_dbg_check_halloc_lock(Process *p); diff --git a/erts/etc/common/erlexec.c b/erts/etc/common/erlexec.c index 19b3bb82ef..a49d10d6f3 100644 --- a/erts/etc/common/erlexec.c +++ b/erts/etc/common/erlexec.c @@ -121,6 +121,7 @@ static char *plusM_other_switches[] = { /* +s arguments with values */ static char *pluss_val_switches[] = { "bt", + "bwt", "cl", "ct", "wt", -- cgit v1.2.3