From 15869e302e4f15c4c46bf5dc4bdf2aea96f513e0 Mon Sep 17 00:00:00 2001 From: Garrett D'Amore Date: Mon, 24 Feb 2020 05:57:35 -0800 Subject: fixes #1202 More than 120 threads was started by NNG This introduces a new CMake option, NNG_MAX_TASKQ_THREADS, with a default value of 16. The number of taskq workers will generally be calculated as vcpu * 2. This new value, if not zero, sets an upper bound. Note that the value should be at least two, in order to ensure no deadlocks occur. --- CMakeLists.txt | 8 +++++++- src/core/taskq.c | 5 +++++ 2 files changed, 12 insertions(+), 1 deletion(-) diff --git a/CMakeLists.txt b/CMakeLists.txt index 9685713b..f74a13c1 100644 --- a/CMakeLists.txt +++ b/CMakeLists.txt @@ -135,6 +135,12 @@ if (NNG_NUM_TASKQ_THREADS) endif () mark_as_advanced(NNG_NUM_TASKQ_THREADS) +set(NNG_MAX_TASKQ_THREADS 16 CACHE STRING "Upper bound on taskq threads, 0 for no limit") +mark_as_advanced(NNG_MAX_TASKQ_THREADS) +if (NNG_MAX_TASKQ_THREADS) + add_definitions(-DNNG_MAX_TASKQ_THREADS=${NNG_MAX_TASKQ_THREADS}) +endif () + # Platform checks. if (CMAKE_C_COMPILER_ID STREQUAL "GNU") @@ -152,7 +158,7 @@ endif () include(CheckAtomicLib) CheckAtomicLib() if (NOT HAVE_C_ATOMICS_WITHOUT_LIB AND HAVE_C_ATOMICS_WITH_LIB) - list(APPEND NNG_LIBS "atomic") + list(APPEND NNG_LIBS "atomic") endif () diff --git a/src/core/taskq.c b/src/core/taskq.c index 09e822df..e63e33c7 100644 --- a/src/core/taskq.c +++ b/src/core/taskq.c @@ -228,6 +228,11 @@ nni_taskq_sys_init(void) #else nthrs = NNG_NUM_TASKQ_THREADS; #endif +#if NNG_MAX_TASKQ_THREADS > 0 + if (nthrs > NNG_MAX_TASKQ_THREADS) { + nthrs = NNG_MAX_TASKQ_THREADS; + } +#endif return (nni_taskq_init(&nni_taskq_systq, nthrs)); } -- cgit v1.2.3-70-g09d2