aboutsummaryrefslogtreecommitdiffstats
diff options
context:
space:
mode:
-rw-r--r--erts/emulator/beam/time.c499
-rw-r--r--erts/etc/unix/etp-commands.in75
2 files changed, 390 insertions, 184 deletions
diff --git a/erts/emulator/beam/time.c b/erts/emulator/beam/time.c
index 16e4328a05..f530ee5de0 100644
--- a/erts/emulator/beam/time.c
+++ b/erts/emulator/beam/time.c
@@ -141,20 +141,24 @@
*
* In order to limit the amount of work needed in order to find
* next timeout, we keep track of total amount of timers in the
- * wheels, total amount of timers in soon wheel, and the total
- * amount of timers in each range of slots. Each slot range
- * currently contain 512 slots.
+ * wheels, total amount of timers in the later wheel, total amount
+ * of timers in soon wheel, and the total amount of timers in
+ * each range of slots. Each slot range currently contain 512
+ * slots.
*
- * When next timeout is less than half the soon wheel width away
- * we determine the exact timeout. Due to the timer counts of
+ * When next timeout is less than the soon wheel width away we
+ * determine the exact timeout. Due to the timer counts of
* slot ranges, we currently at most need to search 1024 slots
* in the soon wheel. This besides inspecting slot range counts
* and two slots in the later wheel which potentially might trigger
* timeouts for moving timers from the later wheel to the soon wheel
- * earlier than timeouts in the soon wheel.
+ * earlier than timeouts in the soon wheel. We also keep track
+ * of latest known minimum timeout position in each wheel which
+ * makes it possible to avoid scanning from current position
+ * each time.
*
- * When next timeout is further away than half the soon wheel
- * width we settle for the earliest possible timeout in the first
+ * When next timeout is further away than the soon wheel width
+ * we settle for the earliest possible timeout in the first
* non-empty slot range. The further away the next timeout is, the
* more likely it is that the next timeout change before we
* actually get there. That is, a change due to another timer is
@@ -176,8 +180,11 @@
#define ERTS_WANT_TIMER_WHEEL_API
#include "erl_time.h"
-#define ERTS_MONOTONIC_WEEK ERTS_SEC_TO_MONOTONIC(7*60*60*24)
-#define ERTS_CLKTCKS_WEEK ERTS_MONOTONIC_TO_CLKTCKS(ERTS_MONOTONIC_WEEK)
+#define ERTS_MAX_CLKTCKS \
+ ERTS_MONOTONIC_TO_CLKTCKS(ERTS_MONOTONIC_TIME_MAX)
+
+#define ERTS_CLKTCKS_WEEK \
+ ERTS_MONOTONIC_TO_CLKTCKS(ERTS_SEC_TO_MONOTONIC(7*60*60*24))
#ifdef ERTS_ENABLE_LOCK_CHECK
#define ASSERT_NO_LOCKED_LOCKS erts_lc_check_exact(NULL, 0)
@@ -265,10 +272,21 @@ static int tiw_itime; /* Constant after init */
# define TIW_ITIME tiw_itime
#endif
+const int etp_tw_soon_wheel_size = ERTS_TW_SOON_WHEEL_SIZE;
+const ErtsMonotonicTime etp_tw_soon_wheel_mask = ERTS_TW_SOON_WHEEL_MASK;
+const int etp_tw_soon_wheel_first_slot = ERTS_TW_SOON_WHEEL_FIRST_SLOT;
+
+const int etp_tw_later_wheel_size = ERTS_TW_LATER_WHEEL_SIZE;
+const ErtsMonotonicTime etp_tw_later_wheel_slot_size = ERTS_TW_LATER_WHEEL_SLOT_SIZE;
+const int etp_tw_later_wheel_shift = ERTS_TW_LATER_WHEEL_SHIFT;
+const ErtsMonotonicTime etp_tw_later_wheel_mask = ERTS_TW_LATER_WHEEL_MASK;
+const ErtsMonotonicTime etp_tw_later_wheel_pos_mask = ERTS_TW_LATER_WHEEL_POS_MASK;
+const int etp_tw_later_wheel_first_slot = ERTS_TW_LATER_WHEEL_FIRST_SLOT;
+
struct ErtsTimerWheel_ {
ErtsTWheelTimer *slots[1 /* At Once Slot */
+ ERTS_TW_SOON_WHEEL_SIZE /* Soon Wheel Slots */
- + ERTS_TW_LATER_WHEEL_SIZE]; /* Later Wheel Slots */
+ + ERTS_TW_LATER_WHEEL_SIZE]; /* Later Wheel Slots */
ErtsTWheelTimer **w;
Sint scnt[ERTS_TW_SCNT_SIZE];
Sint bump_scnt[ERTS_TW_SCNT_SIZE];
@@ -278,15 +296,20 @@ struct ErtsTimerWheel_ {
Uint nto;
} at_once;
struct {
+ ErtsMonotonicTime min_tpos;
Uint nto;
} soon;
struct {
+ ErtsMonotonicTime min_tpos;
+ int min_tpos_slot;
ErtsMonotonicTime pos;
+ Uint nto;
} later;
int yield_slot;
int yield_slots_left;
ErtsTWheelTimer sentinel;
int true_next_timeout_time;
+ ErtsMonotonicTime next_timeout_pos;
ErtsMonotonicTime next_timeout_time;
};
@@ -297,6 +320,18 @@ struct ErtsTimerWheel_ {
static int bump_later_wheel(ErtsTimerWheel *tiw, int *yield_count_p);
+#ifdef ERTS_TW_DEBUG
+#define ERTS_TW_DBG_VERIFY_EMPTY_SOON_SLOTS(TIW, TO_POS) \
+ dbg_verify_empty_soon_slots((TIW), (TO_POS))
+#define ERTS_TW_DBG_VERIFY_EMPTY_LATER_SLOTS(TIW, TO_POS) \
+ dbg_verify_empty_later_slots((TIW), (TO_POS))
+void dbg_verify_empty_soon_slots(ErtsTimerWheel *, ErtsMonotonicTime);
+void dbg_verify_empty_later_slots(ErtsTimerWheel *, ErtsMonotonicTime);
+#else
+#define ERTS_TW_DBG_VERIFY_EMPTY_SOON_SLOTS(TIW, TO_POS)
+#define ERTS_TW_DBG_VERIFY_EMPTY_LATER_SLOTS(TIW, TO_POS)
+#endif
+
static ERTS_INLINE int
scnt_get_ix(int slot)
{
@@ -434,47 +469,59 @@ static void hrd_dbg_check_wheels(ErtsTimerWheel *tiw, int check_min_tpos);
#endif
static ErtsMonotonicTime
-find_next_timeout(ErtsSchedulerData *esdp, ErtsTimerWheel *tiw, int thorough)
+find_next_timeout(ErtsSchedulerData *esdp, ErtsTimerWheel *tiw)
{
int slot, slots;
int true_min_timeout = 0;
- ErtsMonotonicTime min_timeout, min_timeout_pos, slot_timeout_pos;
+ ErtsMonotonicTime min_timeout_pos;
+
+ ERTS_TW_ASSERT(tiw->pos + ERTS_TW_LATER_WHEEL_SLOT_SIZE < tiw->later.pos
+ && tiw->later.pos <= tiw->pos + ERTS_TW_SOON_WHEEL_SIZE);
ERTS_HARD_DBG_CHK_WHEELS(tiw, 0);
ERTS_TW_ASSERT(tiw->yield_slot == ERTS_TW_SLOT_INACTIVE);
if (tiw->nto == 0) { /* no timeouts in wheel */
- if (!thorough)
- min_timeout_pos = tiw->pos;
- else {
- ErtsMonotonicTime curr_time = erts_get_monotonic_time(esdp);
- tiw->pos = min_timeout_pos = ERTS_MONOTONIC_TO_CLKTCKS(curr_time);
- }
- min_timeout_pos += ERTS_MONOTONIC_TO_CLKTCKS(ERTS_MONOTONIC_WEEK);
+ ErtsMonotonicTime curr_time = erts_get_monotonic_time(esdp);
+ tiw->pos = min_timeout_pos = ERTS_MONOTONIC_TO_CLKTCKS(curr_time);
+ tiw->later.pos = min_timeout_pos + ERTS_TW_SOON_WHEEL_SIZE;
+ tiw->later.pos &= ERTS_TW_LATER_WHEEL_POS_MASK;
+ min_timeout_pos += ERTS_CLKTCKS_WEEK;
goto done;
}
- min_timeout_pos = tiw->pos;
- if (thorough)
- min_timeout_pos += ERTS_MONOTONIC_TO_CLKTCKS(ERTS_MONOTONIC_WEEK);
- else
- min_timeout_pos += ERTS_TW_SOON_WHEEL_SIZE/2;
+ ERTS_TW_ASSERT(tiw->soon.nto || tiw->later.nto);
if (!tiw->soon.nto) {
- ErtsMonotonicTime tmp;
- /* Select later wheel... */
- slot_timeout_pos = tiw->later.pos;
- slot = later_slot(slot_timeout_pos);
- /* Pre-timeout for move from later to soon wheel... */
- slot_timeout_pos -= ERTS_TW_LATER_WHEEL_SLOT_SIZE;
- tmp = min_timeout_pos - slot_timeout_pos;
- tmp /= ERTS_TW_LATER_WHEEL_SLOT_SIZE;
- tmp++;
- if (tmp > ERTS_TW_LATER_WHEEL_SIZE)
+ ErtsMonotonicTime tpos, min_tpos;
+
+ /* Search later wheel... */
+
+ min_tpos = tiw->later.min_tpos & ERTS_TW_LATER_WHEEL_POS_MASK;
+
+ if (min_tpos <= tiw->later.pos) {
+ tpos = tiw->later.pos;
slots = ERTS_TW_LATER_WHEEL_SIZE;
- else
- slots = (int) tmp;
+ }
+ else {
+ ErtsMonotonicTime tmp;
+ /* Don't inspect slots we know are empty... */
+ tmp = min_tpos - tiw->later.pos;
+ tmp /= ERTS_TW_LATER_WHEEL_SLOT_SIZE;
+ if (tmp >= ERTS_TW_LATER_WHEEL_SIZE) {
+ /* Timeout more than one revolution ahead... */
+
+ /* Pre-timeout for move from later to soon wheel... */
+ min_timeout_pos = min_tpos - ERTS_TW_LATER_WHEEL_SLOT_SIZE;
+ goto done;
+ }
+ tpos = min_tpos;
+ ERTS_TW_DBG_VERIFY_EMPTY_LATER_SLOTS(tiw, min_tpos);
+ slots = ERTS_TW_LATER_WHEEL_SIZE - ((int) tmp);
+ }
+
+ slot = later_slot(tpos);
/*
* We never search for an exact timeout in the
@@ -484,13 +531,21 @@ find_next_timeout(ErtsSchedulerData *esdp, ErtsTimerWheel *tiw, int thorough)
if (tiw->w[slot])
true_min_timeout = 1;
else
- scnt_later_wheel_next(&slot, &slots, &slot_timeout_pos,
- NULL, tiw->scnt);
- min_timeout_pos = slot_timeout_pos;
+ scnt_later_wheel_next(&slot, &slots, &tpos, NULL, tiw->scnt);
+
+ tiw->later.min_tpos = tpos;
+ tiw->later.min_tpos_slot = slot;
+ ERTS_TW_ASSERT(slot == later_slot(tpos));
+
+ /* Pre-timeout for move from later to soon wheel... */
+ tpos -= ERTS_TW_LATER_WHEEL_SLOT_SIZE;
+ min_timeout_pos = tpos;
}
else {
- ErtsMonotonicTime tmp;
- /* Select soon wheel... */
+ ErtsMonotonicTime tpos;
+ /* Search soon wheel... */
+
+ min_timeout_pos = tiw->pos + ERTS_TW_SOON_WHEEL_SIZE;
/*
* Besides inspecting the soon wheel we
@@ -498,64 +553,72 @@ find_next_timeout(ErtsSchedulerData *esdp, ErtsTimerWheel *tiw, int thorough)
* later wheel which potentially can trigger
* timeouts before timeouts in soon wheel...
*/
- slot_timeout_pos = tiw->later.pos;
- slot_timeout_pos -= ERTS_TW_LATER_WHEEL_SLOT_SIZE;
- if (slot_timeout_pos < min_timeout_pos) {
- int fslot = later_slot(tiw->later.pos);
- if (tiw->w[fslot]) {
- min_timeout_pos = slot_timeout_pos;
- true_min_timeout = 1;
- }
+ if (tiw->later.min_tpos > (tiw->later.pos
+ + 2*ERTS_TW_LATER_WHEEL_SLOT_SIZE)) {
+ ERTS_TW_DBG_VERIFY_EMPTY_LATER_SLOTS(
+ tiw, 2*ERTS_TW_LATER_WHEEL_SLOT_SIZE);
+ }
+ else {
+ int fslot;
+ tpos = tiw->later.pos;
+ tpos -= ERTS_TW_LATER_WHEEL_SLOT_SIZE;
+ fslot = later_slot(tiw->later.pos);
+ if (tiw->w[fslot])
+ min_timeout_pos = tpos;
else {
- slot_timeout_pos += ERTS_TW_LATER_WHEEL_SLOT_SIZE;
- if (slot_timeout_pos < min_timeout_pos) {
+ tpos += ERTS_TW_LATER_WHEEL_SLOT_SIZE;
+ if (tpos < min_timeout_pos) {
fslot++;
if (fslot == ERTS_TW_LATER_WHEEL_END_SLOT)
fslot = ERTS_TW_LATER_WHEEL_FIRST_SLOT;
- if (tiw->w[fslot]) {
- min_timeout_pos = slot_timeout_pos;
- true_min_timeout = 1;
- }
+ if (tiw->w[fslot])
+ min_timeout_pos = tpos;
}
}
}
- slot_timeout_pos = tiw->pos;
- slot = soon_slot(tiw->pos);
- tmp = min_timeout_pos - slot_timeout_pos;
- if (tmp > ERTS_TW_SOON_WHEEL_SIZE)
+ if (tiw->soon.min_tpos <= tiw->pos) {
+ tpos = tiw->pos;
slots = ERTS_TW_SOON_WHEEL_SIZE;
- else
- slots = (int) tmp;
+ }
+ else {
+ ErtsMonotonicTime tmp;
+ /* Don't inspect slots we know are empty... */
+ tmp = tiw->soon.min_tpos - tiw->pos;
+ ERTS_TW_ASSERT(ERTS_TW_SOON_WHEEL_SIZE > tmp);
+ ERTS_TW_DBG_VERIFY_EMPTY_SOON_SLOTS(tiw, tiw->soon.min_tpos);
+ slots = ERTS_TW_SOON_WHEEL_SIZE - ((int) tmp);
+ tpos = tiw->soon.min_tpos;
+ }
- while (slot_timeout_pos < min_timeout_pos) {
+ slot = soon_slot(tpos);
+
+ /* find next non-empty slot */
+ while (tpos < min_timeout_pos) {
if (tiw->w[slot]) {
- ERTS_TW_ASSERT(tiw->w[slot]->timeout_pos == slot_timeout_pos);
- min_timeout_pos = slot_timeout_pos;
- true_min_timeout = 1;
+ ERTS_TW_ASSERT(tiw->w[slot]->timeout_pos == tpos);
+ min_timeout_pos = tpos;
break;
}
- scnt_soon_wheel_next(&slot, &slots, &slot_timeout_pos,
- NULL, tiw->scnt);
+ scnt_soon_wheel_next(&slot, &slots, &tpos, NULL, tiw->scnt);
}
- if (slots > 0 && !true_min_timeout) {
- /* Find first non-empty range... */
- scnt_soon_wheel_next(&slot, &slots, &slot_timeout_pos,
- NULL, tiw->scnt);
- min_timeout_pos = slot_timeout_pos;
- }
+ tiw->soon.min_tpos = min_timeout_pos;
+ true_min_timeout = 1;
}
-done:
+done: {
+ ErtsMonotonicTime min_timeout;
- min_timeout = ERTS_CLKTCKS_TO_MONOTONIC(min_timeout_pos);
- tiw->next_timeout_time = min_timeout;
- tiw->true_next_timeout_time = true_min_timeout;
+ min_timeout = ERTS_CLKTCKS_TO_MONOTONIC(min_timeout_pos);
+ tiw->next_timeout_pos = min_timeout_pos;
+ tiw->next_timeout_time = min_timeout;
+ tiw->true_next_timeout_time = true_min_timeout;
- ERTS_HARD_DBG_CHK_WHEELS(tiw, 1);
+ ERTS_HARD_DBG_CHK_WHEELS(tiw, 1);
- return min_timeout;
+ return min_timeout;
+ }
}
static ERTS_INLINE void
@@ -581,9 +644,20 @@ insert_timer_into_slot(ErtsTimerWheel *tiw, int slot, ErtsTWheelTimer *p)
if (slot == ERTS_TW_SLOT_AT_ONCE)
tiw->at_once.nto++;
else {
+ ErtsMonotonicTime tpos = p->timeout_pos;
if (slot < ERTS_TW_SOON_WHEEL_END_SLOT) {
ERTS_TW_ASSERT(p->timeout_pos < tiw->pos + ERTS_TW_SOON_WHEEL_SIZE);
tiw->soon.nto++;
+ if (tiw->soon.min_tpos > tpos)
+ tiw->soon.min_tpos = tpos;
+ }
+ else {
+ ERTS_TW_ASSERT(p->timeout_pos >= tiw->pos + ERTS_TW_SOON_WHEEL_SIZE);
+ tiw->later.nto++;
+ if (tiw->later.min_tpos > tpos) {
+ tiw->later.min_tpos = tpos;
+ tiw->later.min_tpos_slot = slot;
+ }
}
scnt_inc(tiw->scnt, slot);
}
@@ -593,6 +667,7 @@ static ERTS_INLINE void
remove_timer(ErtsTimerWheel *tiw, ErtsTWheelTimer *p)
{
int slot = p->slot;
+ int empty_slot;
ERTS_TW_ASSERT(slot != ERTS_TW_SLOT_INACTIVE);
/*
@@ -608,21 +683,45 @@ remove_timer(ErtsTimerWheel *tiw, ErtsTWheelTimer *p)
/* Cannot be referred by sentinel, i.e. must be referred by slot... */
ERTS_TW_ASSERT(tiw->w[slot] == p);
tiw->w[slot] = NULL;
+ empty_slot = 1;
}
else {
if (tiw->w[slot] == p)
tiw->w[slot] = p->next;
p->prev->next = p->next;
p->next->prev = p->prev;
+ empty_slot = 0;
}
if (slot == ERTS_TW_SLOT_AT_ONCE) {
ERTS_TW_ASSERT(tiw->at_once.nto > 0);
tiw->at_once.nto--;
}
else {
- if (slot < ERTS_TW_SOON_WHEEL_END_SLOT)
- tiw->soon.nto--;
scnt_dec(tiw->scnt, slot);
+ if (slot < ERTS_TW_SOON_WHEEL_END_SLOT) {
+ if (empty_slot
+ && tiw->true_next_timeout_time
+ && p->timeout_pos == tiw->next_timeout_pos) {
+ tiw->true_next_timeout_time = 0;
+ }
+ if (--tiw->soon.nto == 0)
+ tiw->soon.min_tpos = ERTS_MAX_CLKTCKS;
+ }
+ else {
+ if (empty_slot
+ && tiw->true_next_timeout_time
+ && tiw->later.min_tpos_slot == slot) {
+ ErtsMonotonicTime tpos = tiw->later.min_tpos;
+ tpos &= ERTS_TW_LATER_WHEEL_POS_MASK;
+ tpos -= ERTS_TW_LATER_WHEEL_SLOT_SIZE;
+ if (tpos == tiw->next_timeout_pos)
+ tiw->true_next_timeout_time = 0;
+ }
+ if (--tiw->later.nto == 0) {
+ tiw->later.min_tpos = ERTS_MAX_CLKTCKS;
+ tiw->later.min_tpos_slot = ERTS_TW_LATER_WHEEL_END_SLOT;
+ }
+ }
}
p->slot = ERTS_TW_SLOT_INACTIVE;
}
@@ -633,82 +732,18 @@ erts_check_next_timeout_time(ErtsSchedulerData *esdp)
ErtsTimerWheel *tiw = esdp->timer_wheel;
ErtsMonotonicTime time;
ERTS_MSACC_DECLARE_CACHE_X();
+ ERTS_TW_ASSERT(tiw->next_timeout_time
+ == ERTS_CLKTCKS_TO_MONOTONIC(tiw->next_timeout_pos));
if (tiw->true_next_timeout_time)
- return tiw->next_timeout_time;
+ return tiw->next_timeout_time; /* known timeout... */
+ if (tiw->next_timeout_pos > tiw->pos + ERTS_TW_SOON_WHEEL_SIZE)
+ return tiw->next_timeout_time; /* sufficiently later away... */
ERTS_MSACC_PUSH_AND_SET_STATE_CACHED_X(ERTS_MSACC_STATE_TIMERS);
- time = find_next_timeout(esdp, tiw, 1);
+ time = find_next_timeout(esdp, tiw);
ERTS_MSACC_POP_STATE_M_X();
return time;
}
-#ifndef ERTS_TW_DEBUG
-#define ERTS_DBG_CHK_SAFE_TO_SKIP_TO(TIW, TO) ((void) 0)
-#else
-#define ERTS_DBG_CHK_SAFE_TO_SKIP_TO(TIW, TO) debug_check_safe_to_skip_to((TIW), (TO))
-static void
-debug_check_safe_to_skip_to(ErtsTimerWheel *tiw, ErtsMonotonicTime skip_to_pos)
-{
- int slots, ix;
- ErtsTWheelTimer *tmr;
- ErtsMonotonicTime tmp;
-
- ix = soon_slot(tiw->pos);
- tmp = skip_to_pos - tiw->pos;
- ERTS_TW_ASSERT(tmp >= 0);
- if (tmp < (ErtsMonotonicTime) ERTS_TW_SOON_WHEEL_SIZE)
- slots = (int) tmp;
- else
- slots = ERTS_TW_SOON_WHEEL_SIZE;
-
- while (slots > 0) {
- tmr = tiw->w[ix];
- if (tmr) {
- ErtsTWheelTimer *end = tmr;
- do {
- ERTS_TW_ASSERT(tmr->timeout_pos > skip_to_pos);
- tmr = tmr->next;
- } while (tmr != end);
- }
- ix++;
- if (ix == ERTS_TW_SOON_WHEEL_END_SLOT)
- ix = ERTS_TW_SOON_WHEEL_FIRST_SLOT;
- slots--;
- }
-
- ix = later_slot(tiw->later.pos);
- tmp = skip_to_pos;
- tmp &= ERTS_TW_LATER_WHEEL_POS_MASK;
- if (tmp >= tiw->later.pos) {
- tmp -= tiw->later.pos;
- tmp /= ERTS_TW_LATER_WHEEL_SLOT_SIZE;
- tmp++;
- ERTS_TW_ASSERT(tmp >= 0);
- if (tmp < (ErtsMonotonicTime) ERTS_TW_LATER_WHEEL_SIZE)
- slots = (int) tmp;
- else
- slots = ERTS_TW_LATER_WHEEL_SIZE;
-
- while (slots > 0) {
- tmr = tiw->w[ix];
- if (tmr) {
- ErtsMonotonicTime tpos = tmr->timeout_pos;
- ErtsTWheelTimer *end = tmr;
- do {
- tpos &= ERTS_TW_LATER_WHEEL_POS_MASK;
- tpos -= ERTS_TW_LATER_WHEEL_SLOT_SIZE;
- ERTS_TW_ASSERT(tpos > skip_to_pos);
- tmr = tmr->next;
- } while (tmr != end);
- }
- ix++;
- if (ix == ERTS_TW_LATER_WHEEL_END_SLOT)
- ix = ERTS_TW_LATER_WHEEL_FIRST_SLOT;
- slots--;
- }
- }
-}
-#endif
-
static ERTS_INLINE void
timeout_timer(ErtsTWheelTimer *p)
{
@@ -758,16 +793,23 @@ erts_bump_timers(ErtsTimerWheel *tiw, ErtsMonotonicTime curr_time)
restarted = 0;
bump_to = ERTS_MONOTONIC_TO_CLKTCKS(curr_time);
+ tiw->true_next_timeout_time = 1;
+ tiw->next_timeout_pos = bump_to;
+ tiw->next_timeout_time = ERTS_CLKTCKS_TO_MONOTONIC(bump_to);
while (1) {
ErtsTWheelTimer *p;
if (tiw->nto == 0) {
empty_wheel:
- ERTS_DBG_CHK_SAFE_TO_SKIP_TO(tiw, bump_to);
+ ERTS_TW_DBG_VERIFY_EMPTY_SOON_SLOTS(tiw, bump_to);
+ ERTS_TW_DBG_VERIFY_EMPTY_LATER_SLOTS(tiw, bump_to);
tiw->true_next_timeout_time = 0;
- tiw->next_timeout_time = curr_time + ERTS_MONOTONIC_WEEK;
+ tiw->next_timeout_pos = bump_to + ERTS_CLKTCKS_WEEK;
+ tiw->next_timeout_time = ERTS_CLKTCKS_TO_MONOTONIC(tiw->next_timeout_pos);;
tiw->pos = bump_to;
+ tiw->later.pos = bump_to + ERTS_TW_SOON_WHEEL_SIZE;
+ tiw->later.pos &= ERTS_TW_LATER_WHEEL_POS_MASK;
tiw->yield_slot = ERTS_TW_SLOT_INACTIVE;
ERTS_MSACC_POP_STATE_M_X();
return;
@@ -811,8 +853,6 @@ erts_bump_timers(ErtsTimerWheel *tiw, ErtsMonotonicTime curr_time)
ERTS_TW_ASSERT(tiw->nto > 0);
ERTS_TW_ASSERT(tiw->at_once.nto > 0);
tiw->yield_slot = ERTS_TW_SLOT_AT_ONCE;
- tiw->true_next_timeout_time = 1;
- tiw->next_timeout_time = ERTS_CLKTCKS_TO_MONOTONIC(bump_to);
ERTS_MSACC_POP_STATE_M_X();
return; /* Yield! */
}
@@ -847,28 +887,22 @@ erts_bump_timers(ErtsTimerWheel *tiw, ErtsMonotonicTime curr_time)
sys_memcpy((void *) bump_scnt, (void *) scnt,
sizeof(Sint) * ERTS_TW_SCNT_SIZE);
- if (tiw->true_next_timeout_time) {
- ErtsMonotonicTime skip_until_pos;
+ if (tiw->soon.min_tpos > tiw->pos) {
+ ErtsMonotonicTime skip_until_pos = tiw->soon.min_tpos;
+
/*
* No need inspecting slots where we know no timeouts
* to trigger should reside.
*/
- skip_until_pos = ERTS_MONOTONIC_TO_CLKTCKS(tiw->next_timeout_time);
if (skip_until_pos > bump_to)
skip_until_pos = bump_to;
skip_until_pos--;
if (skip_until_pos > tiw->pos) {
- ERTS_DBG_CHK_SAFE_TO_SKIP_TO(tiw, skip_until_pos);
-
+ ERTS_TW_DBG_VERIFY_EMPTY_SOON_SLOTS(tiw, skip_until_pos);
tiw->pos = skip_until_pos;
-
- skip_until_pos++;
- skip_until_pos &= ERTS_TW_LATER_WHEEL_POS_MASK;
- if (tiw->later.pos < skip_until_pos)
- tiw->later.pos = skip_until_pos;
}
}
@@ -884,6 +918,9 @@ erts_bump_timers(ErtsTimerWheel *tiw, ErtsMonotonicTime curr_time)
slot = soon_slot(tiw->pos+1);
tiw->pos = bump_to;
+ tiw->next_timeout_pos = bump_to;
+ tiw->next_timeout_time = ERTS_CLKTCKS_TO_MONOTONIC(bump_to);
+
scnt_ix = scnt_get_ix(slot);
/* Timeout timers in soon wheel */
@@ -910,7 +947,8 @@ erts_bump_timers(ErtsTimerWheel *tiw, ErtsMonotonicTime curr_time)
ERTS_TW_ASSERT(ERTS_TW_SOON_WHEEL_FIRST_SLOT <= p->slot
&& p->slot < ERTS_TW_SOON_WHEEL_END_SLOT);
- tiw->soon.nto--;
+ if (--tiw->soon.nto == 0)
+ tiw->soon.min_tpos = ERTS_MAX_CLKTCKS;
scnt_ix_dec(scnt, scnt_ix);
if (p->timeout_pos <= bump_to) {
timeout_timer(p);
@@ -933,8 +971,6 @@ erts_bump_timers(ErtsTimerWheel *tiw, ErtsMonotonicTime curr_time)
}
if (yield_count <= 0) {
- tiw->true_next_timeout_time = 1;
- tiw->next_timeout_time = ERTS_CLKTCKS_TO_MONOTONIC(bump_to);
tiw->yield_slot = slot;
tiw->yield_slots_left = slots;
ERTS_MSACC_POP_STATE_M_X();
@@ -959,9 +995,9 @@ erts_bump_timers(ErtsTimerWheel *tiw, ErtsMonotonicTime curr_time)
} while (restarted);
tiw->true_next_timeout_time = 0;
- tiw->next_timeout_time = curr_time + ERTS_MONOTONIC_WEEK;
+ ERTS_TW_ASSERT(tiw->next_timeout_pos == bump_to);
- (void) find_next_timeout(NULL, tiw, 0);
+ (void) find_next_timeout(NULL, tiw);
ERTS_MSACC_POP_STATE_M_X();
}
@@ -988,15 +1024,31 @@ bump_later_wheel(ErtsTimerWheel *tiw, int *ycount_p)
goto restart_yielded_slot;
}
else {
- ErtsMonotonicTime tmp_slots = cpos;
- tmp_slots += ERTS_TW_LATER_WHEEL_SLOT_SIZE;
+ ErtsMonotonicTime end_later_pos, tmp_slots, min_tpos;
+
+ min_tpos = tiw->later.min_tpos & ERTS_TW_LATER_WHEEL_POS_MASK;
+ end_later_pos = cpos + ERTS_TW_SOON_WHEEL_SIZE;
+ end_later_pos &= ERTS_TW_LATER_WHEEL_POS_MASK;
+
+ /* Skip known empty slots... */
+ if (min_tpos > later_pos) {
+ if (min_tpos > end_later_pos) {
+ later_pos = end_later_pos;
+ ERTS_TW_DBG_VERIFY_EMPTY_LATER_SLOTS(tiw, later_pos);
+ goto done;
+ }
+ later_pos = min_tpos;
+ ERTS_TW_DBG_VERIFY_EMPTY_LATER_SLOTS(tiw, later_pos);
+ }
+
+ tmp_slots = end_later_pos;
tmp_slots -= later_pos;
tmp_slots /= ERTS_TW_LATER_WHEEL_SLOT_SIZE;
- tmp_slots++;
if (tmp_slots < ERTS_TW_LATER_WHEEL_SIZE)
slots = (int) tmp_slots;
else
slots = ERTS_TW_LATER_WHEEL_SIZE;
+
fslot = later_slot(later_pos);
scnt_ix = scnt_get_ix(fslot);
}
@@ -1028,6 +1080,10 @@ bump_later_wheel(ErtsTimerWheel *tiw, int *ycount_p)
ERTS_TW_ASSERT(tpos >= later_pos);
ERTS_TW_ASSERT(p->slot == fslot);
+ if (--tiw->later.nto == 0) {
+ tiw->later.min_tpos = ERTS_MAX_CLKTCKS;
+ tiw->later.min_tpos_slot = ERTS_TW_LATER_WHEEL_END_SLOT;
+ }
scnt_ix_dec(scnt, scnt_ix);
if (tpos >= later_pos + ERTS_TW_LATER_WHEEL_SLOT_SIZE) {
@@ -1061,8 +1117,6 @@ bump_later_wheel(ErtsTimerWheel *tiw, int *ycount_p)
if (ycount < 0) {
tiw->later.pos = later_pos;
- tiw->true_next_timeout_time = 1;
- tiw->next_timeout_time = ERTS_CLKTCKS_TO_MONOTONIC(cpos);
tiw->yield_slot = fslot;
tiw->yield_slots_left = slots;
*ycount_p = 0;
@@ -1078,6 +1132,8 @@ bump_later_wheel(ErtsTimerWheel *tiw, int *ycount_p)
scnt_later_wheel_next(&fslot, &slots, &later_pos, &scnt_ix, bump_scnt);
}
+done:
+
ERTS_HARD_DBG_CHK_WHEELS(tiw, 0);
tiw->later.pos = later_pos;
@@ -1129,13 +1185,17 @@ erts_create_timer_wheel(ErtsSchedulerData *esdp)
tiw->pos = ERTS_MONOTONIC_TO_CLKTCKS(mtime);
tiw->nto = 0;
tiw->at_once.nto = 0;
+ tiw->soon.min_tpos = ERTS_MAX_CLKTCKS;
tiw->soon.nto = 0;
- tiw->later.pos = tiw->pos;
+ tiw->later.min_tpos = ERTS_MAX_CLKTCKS;
+ tiw->later.min_tpos_slot = ERTS_TW_LATER_WHEEL_END_SLOT;
+ tiw->later.pos = tiw->pos + ERTS_TW_SOON_WHEEL_SIZE;
tiw->later.pos &= ERTS_TW_LATER_WHEEL_POS_MASK;
- tiw->later.pos += ERTS_TW_LATER_WHEEL_SLOT_SIZE;
+ tiw->later.nto = 0;
tiw->yield_slot = ERTS_TW_SLOT_INACTIVE;
tiw->true_next_timeout_time = 0;
- tiw->next_timeout_time = mtime + ERTS_MONOTONIC_WEEK;
+ tiw->next_timeout_pos = tiw->pos + ERTS_CLKTCKS_WEEK;
+ tiw->next_timeout_time = ERTS_CLKTCKS_TO_MONOTONIC(tiw->next_timeout_pos);
tiw->sentinel.next = &tiw->sentinel;
tiw->sentinel.prev = &tiw->sentinel;
tiw->sentinel.timeout = NULL;
@@ -1175,7 +1235,6 @@ erts_twheel_set_timer(ErtsTimerWheel *tiw,
void *arg, ErtsMonotonicTime timeout_pos)
{
int slot;
- ErtsMonotonicTime timeout_time;
ERTS_MSACC_PUSH_AND_SET_STATE_M_X(ERTS_MSACC_STATE_TIMERS);
p->timeout = timeout;
@@ -1195,6 +1254,8 @@ erts_twheel_set_timer(ErtsTimerWheel *tiw,
/* soon wheel */
p->timeout_pos = timeout_pos;
slot = soon_slot(timeout_pos);
+ if (tiw->soon.min_tpos > timeout_pos)
+ tiw->soon.min_tpos = timeout_pos;
}
else {
/* later wheel */
@@ -1214,11 +1275,13 @@ erts_twheel_set_timer(ErtsTimerWheel *tiw,
}
insert_timer_into_slot(tiw, slot, p);
- timeout_time = ERTS_CLKTCKS_TO_MONOTONIC(timeout_pos);
- if (timeout_time < tiw->next_timeout_time) {
+ if (timeout_pos <= tiw->next_timeout_pos) {
tiw->true_next_timeout_time = 1;
- tiw->next_timeout_time = timeout_time;
+ if (timeout_pos < tiw->next_timeout_pos) {
+ tiw->next_timeout_pos = timeout_pos;
+ tiw->next_timeout_time = ERTS_CLKTCKS_TO_MONOTONIC(timeout_pos);
+ }
}
ERTS_MSACC_POP_STATE_M_X();
}
@@ -1264,6 +1327,73 @@ erts_twheel_debug_foreach(ErtsTimerWheel *tiw,
}
}
+#ifdef ERTS_TW_DEBUG
+
+void
+dbg_verify_empty_soon_slots(ErtsTimerWheel *tiw, ErtsMonotonicTime to_pos)
+{
+ int ix;
+ ErtsMonotonicTime tmp;
+
+ ix = soon_slot(tiw->pos);
+ tmp = to_pos;
+ if (tmp > tiw->pos) {
+ int slots;
+ tmp -= tiw->pos;
+ ERTS_TW_ASSERT(tmp > 0);
+ if (tmp < (ErtsMonotonicTime) ERTS_TW_SOON_WHEEL_SIZE)
+ slots = (int) tmp;
+ else
+ slots = ERTS_TW_SOON_WHEEL_SIZE;
+
+ while (slots > 0) {
+ ERTS_TW_ASSERT(!tiw->w[ix]);
+ ix++;
+ if (ix == ERTS_TW_SOON_WHEEL_END_SLOT)
+ ix = ERTS_TW_SOON_WHEEL_FIRST_SLOT;
+ slots--;
+ }
+ }
+}
+
+void
+dbg_verify_empty_later_slots(ErtsTimerWheel *tiw, ErtsMonotonicTime to_pos)
+{
+ int ix;
+ ErtsMonotonicTime tmp;
+
+ ix = later_slot(tiw->later.pos);
+ tmp = to_pos;
+ tmp &= ERTS_TW_LATER_WHEEL_POS_MASK;
+ if (tmp > tiw->later.pos) {
+ int slots;
+ tmp -= tiw->later.pos;
+ tmp /= ERTS_TW_LATER_WHEEL_SLOT_SIZE;
+ ERTS_TW_ASSERT(tmp > 0);
+ if (tmp < (ErtsMonotonicTime) ERTS_TW_LATER_WHEEL_SIZE)
+ slots = (int) tmp;
+ else
+ slots = ERTS_TW_LATER_WHEEL_SIZE;
+
+ while (slots > 0) {
+ ErtsTWheelTimer *tmr = tiw->w[ix];
+ if (tmr) {
+ ErtsTWheelTimer *end = tmr;
+ do {
+ ERTS_TW_ASSERT(tmr->timeout_pos > to_pos);
+ tmr = tmr->next;
+ } while (tmr != end);
+ }
+ ix++;
+ if (ix == ERTS_TW_LATER_WHEEL_END_SLOT)
+ ix = ERTS_TW_LATER_WHEEL_FIRST_SLOT;
+ slots--;
+ }
+ }
+}
+
+#endif /* ERTS_TW_DEBUG */
+
#ifdef ERTS_TW_HARD_DEBUG
static void
@@ -1385,10 +1515,11 @@ hrd_dbg_check_wheels(ErtsTimerWheel *tiw, int check_min_tpos)
ERTS_TW_ASSERT(tiw->at_once.nto == at_once_tmo);
ERTS_TW_ASSERT(tiw->soon.nto == soon_tmo);
+ ERTS_TW_ASSERT(tiw->later.nto == later_tmo);
ERTS_TW_ASSERT(tiw->nto == soon_tmo + later_tmo + at_once_tmo);
for (six = 0; six < ERTS_TW_SCNT_SIZE; six++)
ERTS_TW_ASSERT(scnt[six] == tiw->scnt[six]);
}
-#endif
+#endif /* ERTS_TW_HARD_DEBUG */
diff --git a/erts/etc/unix/etp-commands.in b/erts/etc/unix/etp-commands.in
index c689d495e6..643cfbf323 100644
--- a/erts/etc/unix/etp-commands.in
+++ b/erts/etc/unix/etp-commands.in
@@ -2871,6 +2871,81 @@ define etp-disasm
end
end
+############################################################################
+#
+# Timer Wheel
+#
+
+define etp-timer-wheel
+# Args: TimerWheel
+ if (!erts_initialized)
+ printf "System not initialized!\n"
+ else
+ set $tiw = $arg0
+ printf "Number of timers: %d\n", $tiw->nto
+ printf "Min timeout pos: %d\n", $tiw->next_timeout_pos
+ printf "\n--- Soon Wheel ---\n"
+ set $ix = $tiw->pos & etp_tw_soon_wheel_mask
+ printf "Position: %ld (%d)\n", $tiw->pos, $ix
+ printf "Min timeout position: %ld (%d)\n", $tiw->soon.min_tpos, $tiw->soon.min_tpos & etp_tw_soon_wheel_mask
+ printf "Number of timers: %d\n", $tiw->soon.nto
+ set $slots = etp_tw_soon_wheel_size
+ while $slots > 0
+ set $tmr = $tiw->w[$ix]
+ if ($tmr != (ErtsTWheelTimer *) 0x0)
+ printf "---\n"
+ printf "Slot: %d\n", $ix
+ printf "\n"
+ while 1
+ printf "- Timeout pos: %ld\n", $tmr->timeout_pos
+ printf " Pointer: (ErtsTWheelTimer *) %p\n", $tmr
+ set $tmr = $tmr->next
+ if ($tmr == $tiw->w[$ix])
+ loop_break
+ end
+ end
+ end
+ set $ix++
+ if ($ix == (etp_tw_soon_wheel_first_slot + etp_tw_soon_wheel_size))
+ set $ix = etp_tw_soon_wheel_first_slot
+ end
+ set $slots--
+ end
+ printf "\n--- Later Wheel ---\n"
+ set $ix = (($tiw->later.pos >> etp_tw_later_wheel_shift) & etp_tw_later_wheel_mask) + etp_tw_later_wheel_first_slot
+ printf "Position: %ld (%d)\n", $tiw->later.pos, $ix
+ printf "Min timeout position: %ld (%d)\n", $tiw->later.min_tpos, (($tiw->later.min_tpos >> etp_tw_later_wheel_shift) & etp_tw_later_wheel_mask) + etp_tw_later_wheel_first_slot
+ printf "Number of timers: %d\n", $tiw->later.nto
+ set $slots = etp_tw_later_wheel_size
+ set $slot_pos = $tiw->later.pos
+ while $slots > 0
+ set $tmr = $tiw->w[$ix]
+ if ($tmr != (ErtsTWheelTimer *) 0x0)
+ printf "---\n"
+ printf "Slot: %d\n", $ix
+ printf "Slot Range: [%ld, %ld]\n", $slot_pos, $slot_pos + etp_tw_later_wheel_slot_size
+ printf "Pre timeout pos: %ld\n", $slot_pos - etp_tw_later_wheel_slot_size
+ printf "\n"
+ while 1
+ printf "- Timeout pos: %ld\n", $tmr->timeout_pos
+ printf " Pointer: (ErtsTWheelTimer *) %p\n", $tmr
+ set $tmr = $tmr->next
+ if ($tmr == $tiw->w[$ix])
+ loop_break
+ end
+ end
+ end
+ set $ix++
+ if ($ix == (etp_tw_later_wheel_first_slot + etp_tw_later_wheel_size))
+ set $ix = etp_tw_later_wheel_first_slot
+ end
+ set $slot_pos = $slot_pos + etp_tw_later_wheel_slot_size
+ set $slots--
+ end
+ end
+ printf "---\n"
+end
+
document etp-disasm
%---------------------------------------------------------------------------
% etp-disasm StartI EndI