diff options
-rw-r--r-- | erts/doc/src/erl.xml | 14 | ||||
-rw-r--r-- | erts/emulator/beam/erl_init.c | 16 | ||||
-rw-r--r-- | erts/emulator/beam/erl_process.c | 85 | ||||
-rw-r--r-- | erts/emulator/beam/erl_process.h | 4 | ||||
-rw-r--r-- | erts/etc/common/erlexec.c | 3 | ||||
-rw-r--r-- | erts/vsn.mk | 2 |
6 files changed, 120 insertions, 4 deletions
diff --git a/erts/doc/src/erl.xml b/erts/doc/src/erl.xml index f931445a3e..12cdb4b628 100644 --- a/erts/doc/src/erl.xml +++ b/erts/doc/src/erl.xml @@ -907,6 +907,20 @@ <p>For more information, see <seealso marker="erlang#system_info_cpu_topology">erlang:system_info(cpu_topology)</seealso>.</p> </item> + <tag><marker id="+sfwi"><c>+sfwi Interval</c></marker></tag> + <item> + <p>Set scheduler forced wakeup interval. All run queues will + be scanned each <c>Interval</c> milliseconds. While there are + sleeping schedulers in the system, one scheduler will be woken + for each non-empty run queue found. An <c>Interval</c> of zero + disables this feature, which also is the default. + </p> + <p>This feature has been introduced as a temporary workaround + for lengthy executing native code, and native code that do not + bump reductions properly in OTP. When these bugs have be fixed + the <c>+sfwi</c> flag will be removed. + </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 diff --git a/erts/emulator/beam/erl_init.c b/erts/emulator/beam/erl_init.c index 1eb3dba240..7f52b111ac 100644 --- a/erts/emulator/beam/erl_init.c +++ b/erts/emulator/beam/erl_init.c @@ -1240,6 +1240,22 @@ erl_start(int argc, char **argv) ("suggested scheduler thread stack size %d kilo words\n", erts_sched_thread_suggested_stack_size)); } + else if (has_prefix("fwi", sub_param)) { + long val; + arg = get_arg(sub_param+3, argv[i+1], &i); + errno = 0; + val = strtol(arg, NULL, 10); + if (errno != 0 || val < 0) { + erts_fprintf(stderr, + "bad scheduler forced wakeup " + "interval %s\n", + arg); + erts_usage(); + } +#ifdef ERTS_SMP + erts_runq_supervision_interval = val; +#endif + } else { erts_fprintf(stderr, "bad scheduling option %s\n", argv[i]); erts_usage(); diff --git a/erts/emulator/beam/erl_process.c b/erts/emulator/beam/erl_process.c index 9425fa7088..d7d440d81a 100644 --- a/erts/emulator/beam/erl_process.c +++ b/erts/emulator/beam/erl_process.c @@ -218,6 +218,10 @@ static erts_smp_atomic32_t function_calls; #ifdef ERTS_SMP static erts_smp_atomic32_t doing_sys_schedule; static erts_smp_atomic32_t no_empty_run_queues; +long erts_runq_supervision_interval = 0; +static ethr_event runq_supervision_event; +static erts_tid_t runq_supervisor_tid; +static erts_atomic_t runq_supervisor_sleeping; #else /* !ERTS_SMP */ ErtsSchedulerData *erts_scheduler_data; #endif @@ -1885,7 +1889,13 @@ empty_runq(ErtsRunQueue *rq) */ ASSERT(0 <= empty && empty < 2*erts_no_run_queues); #endif - erts_smp_atomic32_inc_relb(&no_empty_run_queues); + if (!erts_runq_supervision_interval) + erts_smp_atomic32_inc_relb(&no_empty_run_queues); + else { + erts_smp_atomic32_inc_mb(&no_empty_run_queues); + if (erts_atomic_read_nob(&runq_supervisor_sleeping)) + ethr_event_set(&runq_supervision_event); + } } } @@ -1903,7 +1913,14 @@ non_empty_runq(ErtsRunQueue *rq) */ ASSERT(0 < empty && empty <= 2*erts_no_run_queues); #endif - erts_smp_atomic32_dec_relb(&no_empty_run_queues); + if (!erts_runq_supervision_interval) + erts_smp_atomic32_dec_relb(&no_empty_run_queues); + else { + erts_aint32_t no; + no = erts_smp_atomic32_dec_read_mb(&no_empty_run_queues); + if (no > 0 && erts_atomic_read_nob(&runq_supervisor_sleeping)) + ethr_event_set(&runq_supervision_event); + } } } @@ -2505,7 +2522,6 @@ try_inc_no_active_runqs(int active) return 0; } - static ERTS_INLINE int chk_wake_sched(ErtsRunQueue *crq, int ix, int activate) { @@ -3829,6 +3845,53 @@ set_wakeup_other_data(void) } } +static int +no_runqs_to_supervise(void) +{ + int used; + erts_aint32_t nerq = erts_smp_atomic32_read_acqb(&no_empty_run_queues); + if (nerq <= 0) + return 0; + get_no_runqs(NULL, &used); + if (nerq >= used) + return 0; + return used; +} + +static void * +runq_supervisor(void *unused) +{ + while (1) { + int ix, no_rqs; + + erts_milli_sleep(erts_runq_supervision_interval); + no_rqs = no_runqs_to_supervise(); + if (!no_rqs) { + erts_atomic_set_nob(&runq_supervisor_sleeping, 1); + while (1) { + ethr_event_reset(&runq_supervision_event); + no_rqs = no_runqs_to_supervise(); + if (no_rqs) { + erts_atomic_set_nob(&runq_supervisor_sleeping, 0); + break; + } + ethr_event_wait(&runq_supervision_event); + } + } + + for (ix = 0; ix < no_rqs; ix++) { + ErtsRunQueue *rq = ERTS_RUNQ_IX(ix); + if (erts_smp_atomic32_read_acqb(&rq->info_flags) & ERTS_RUNQ_IFLG_NONEMPTY) { + erts_smp_runq_lock(rq); + if (rq->len != 0) + wake_scheduler_on_empty_runq(rq); /* forced wakeup... */ + erts_smp_runq_unlock(rq); + } + } + } + return NULL; +} + #endif void @@ -5235,6 +5298,22 @@ erts_start_schedulers(void) ethr_thr_opts opts = ETHR_THR_OPTS_DEFAULT_INITER; opts.detached = 1; + +#ifdef ERTS_SMP + if (erts_runq_supervision_interval) { + opts.suggested_stack_size = 16; + erts_atomic_init_nob(&runq_supervisor_sleeping, 0); + if (0 != ethr_event_init(&runq_supervision_event)) + erl_exit(1, "Failed to create run-queue supervision event\n"); + if (0 != ethr_thr_create(&runq_supervisor_tid, + runq_supervisor, + NULL, + &opts)) + erl_exit(1, "Failed to create run-queue supervision thread\n"); + + } +#endif + opts.suggested_stack_size = erts_sched_thread_suggested_stack_size; if (wanted < 1) diff --git a/erts/emulator/beam/erl_process.h b/erts/emulator/beam/erl_process.h index 968971ed4c..9b0e9f1ccd 100644 --- a/erts/emulator/beam/erl_process.h +++ b/erts/emulator/beam/erl_process.h @@ -371,6 +371,10 @@ struct ErtsRunQueue_ { } ports; }; +#ifdef ERTS_SMP +extern long erts_runq_supervision_interval; +#endif + typedef union { ErtsRunQueue runq; char align[ERTS_ALC_CACHE_LINE_ALIGN_SIZE(sizeof(ErtsRunQueue))]; diff --git a/erts/etc/common/erlexec.c b/erts/etc/common/erlexec.c index 52add1c1ba..c4bdc4ee4b 100644 --- a/erts/etc/common/erlexec.c +++ b/erts/etc/common/erlexec.c @@ -124,6 +124,9 @@ static char *pluss_val_switches[] = { "bwt", "cl", "ct", + "fwi", + "tbt", + "wct", "wt", "ws", "ss", diff --git a/erts/vsn.mk b/erts/vsn.mk index f522b4c758..7e1d43429c 100644 --- a/erts/vsn.mk +++ b/erts/vsn.mk @@ -17,7 +17,7 @@ # %CopyrightEnd% # -VSN = 5.9.3.2 +VSN = 5.9.3.3 SYSTEM_VSN = R15B03 # Port number 4365 in 4.2 |