From 822f1d7509fe7426a291de1054ea5e9f4892ee15 Mon Sep 17 00:00:00 2001 From: Craig Tiller Date: Sat, 12 Mar 2016 06:54:47 -0800 Subject: Add comment, tighten loop --- src/core/iomgr/timer.c | 15 ++++++++++++--- 1 file changed, 12 insertions(+), 3 deletions(-) diff --git a/src/core/iomgr/timer.c b/src/core/iomgr/timer.c index 8badd83bbb..f444643428 100644 --- a/src/core/iomgr/timer.c +++ b/src/core/iomgr/timer.c @@ -33,11 +33,11 @@ #include "src/core/iomgr/timer.h" -#include "src/core/iomgr/timer_heap.h" -#include "src/core/iomgr/time_averaged_stats.h" #include #include #include +#include "src/core/iomgr/time_averaged_stats.h" +#include "src/core/iomgr/timer_heap.h" #define INVALID_HEAP_INDEX 0xffffffffu @@ -331,8 +331,17 @@ static int run_some_expired_timers(grpc_exec_ctx *exec_ctx, gpr_timespec now, gpr_mu_unlock(&g_mu); gpr_mu_unlock(&g_checker_mu); } else if (next != NULL) { + /* TODO(ctiller): this forces calling code to do an short poll, and + then retry the timer check (because this time through the timer list was + contended). + + We could reduce the cost here dramatically by keeping a count of how many + currently active pollers got through the uncontended case above + successfully, and waking up other pollers IFF that count drops to zero. + + Once that count is in place, this entire else branch could disappear. */ *next = gpr_time_min( - *next, gpr_time_add(now, gpr_time_from_millis(100, GPR_TIMESPAN))); + *next, gpr_time_add(now, gpr_time_from_millis(1, GPR_TIMESPAN))); } return (int)n; -- cgit v1.2.3