From cbfc5310a2ea14cac736fc2c4fbee5cc920c15b1 Mon Sep 17 00:00:00 2001 From: Juanli Shen Date: Wed, 4 Apr 2018 16:15:57 -0700 Subject: Revert "Revert "Use heuristic to determine how many events to handle per iter…" MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit --- src/core/lib/iomgr/ev_epollex_linux.cc | 20 ++++++++++++++++++-- 1 file changed, 18 insertions(+), 2 deletions(-) (limited to 'src') diff --git a/src/core/lib/iomgr/ev_epollex_linux.cc b/src/core/lib/iomgr/ev_epollex_linux.cc index 0ef7c03056..d3cbaf9d0a 100644 --- a/src/core/lib/iomgr/ev_epollex_linux.cc +++ b/src/core/lib/iomgr/ev_epollex_linux.cc @@ -59,7 +59,7 @@ //#define GRPC_EPOLLEX_CREATE_WORKERS_ON_HEAP 1 #define MAX_EPOLL_EVENTS 100 -#define MAX_EPOLL_EVENTS_HANDLED_EACH_POLL_CALL 1 +#define MAX_EPOLL_EVENTS_HANDLED_EACH_POLL_CALL 16 grpc_core::DebugOnlyTraceFlag grpc_trace_pollable_refcount(false, "pollable_refcount"); @@ -198,6 +198,7 @@ struct grpc_pollset_worker { struct grpc_pollset { gpr_mu mu; + gpr_atm worker_count; pollable* active_pollable; bool kicked_without_poller; grpc_closure* shutdown_closure; @@ -685,6 +686,7 @@ static grpc_error* pollset_kick_all(grpc_pollset* pollset) { static void pollset_init(grpc_pollset* pollset, gpr_mu** mu) { gpr_mu_init(&pollset->mu); + gpr_atm_no_barrier_store(&pollset->worker_count, 0); pollset->active_pollable = POLLABLE_REF(g_empty_pollable, "pollset"); pollset->kicked_without_poller = false; pollset->shutdown_closure = nullptr; @@ -758,8 +760,20 @@ static grpc_error* pollable_process_events(grpc_pollset* pollset, pollable* pollable_obj, bool drain) { GPR_TIMER_SCOPE("pollable_process_events", 0); static const char* err_desc = "pollset_process_events"; + // Use a simple heuristic to determine how many fd events to process + // per loop iteration. (events/workers) + int handle_count = 1; + int worker_count = gpr_atm_no_barrier_load(&pollset->worker_count); + GPR_ASSERT(worker_count > 0); + handle_count = + (pollable_obj->event_count - pollable_obj->event_cursor) / worker_count; + if (handle_count == 0) { + handle_count = 1; + } else if (handle_count > MAX_EPOLL_EVENTS_HANDLED_EACH_POLL_CALL) { + handle_count = MAX_EPOLL_EVENTS_HANDLED_EACH_POLL_CALL; + } grpc_error* error = GRPC_ERROR_NONE; - for (int i = 0; (drain || i < MAX_EPOLL_EVENTS_HANDLED_EACH_POLL_CALL) && + for (int i = 0; (drain || i < handle_count) && pollable_obj->event_cursor != pollable_obj->event_count; i++) { int n = pollable_obj->event_cursor++; @@ -884,6 +898,7 @@ static bool begin_worker(grpc_pollset* pollset, grpc_pollset_worker* worker, GPR_TIMER_SCOPE("begin_worker", 0); bool do_poll = (pollset->shutdown_closure == nullptr && !pollset->already_shutdown); + gpr_atm_no_barrier_fetch_add(&pollset->worker_count, 1); if (worker_hdl != nullptr) *worker_hdl = worker; worker->initialized_cv = false; worker->kicked = false; @@ -964,6 +979,7 @@ static void end_worker(grpc_pollset* pollset, grpc_pollset_worker* worker, if (worker->initialized_cv) { gpr_cv_destroy(&worker->cv); } + gpr_atm_no_barrier_fetch_add(&pollset->worker_count, -1); } #ifndef NDEBUG -- cgit v1.2.3