diff options
| author | Ashod Nakashian <ashod.nakashian@collabora.co.uk> | 2016-06-14 07:19:20 -0400 |
|---|---|---|
| committer | Michael Meeks <michael.meeks@collabora.com> | 2016-06-17 09:20:07 +0000 |
| commit | c739cc104844893955dc9a4de2bf8050759703f2 (patch) | |
| tree | 974f908a33c62bda4638090a94bc14c538b124fd /include | |
| parent | 4547fd4c3c58287076a6492d5c9f23ccc45578dc (diff) | |
tdf#98955 hardware_concurrency not ideal for thread pools
A new static member getPreferredConcurrency added to
comphelper::ThreadPool to return a configurable max
number of threads.
By default the new function returns the hardware_concurrency
value provided by std::thread. When MAX_CONCURRENCY envar is
defined, the return value is limited to whatever is set there.
Three call-sites that used std::thread::hardware_concurrency
have been replaced with getPreferredConcurrency.
Unittests added to cover the functionality of the new member.
Unittests are capped to 4 threads.
Reviewed-on: https://gerrit.libreoffice.org/26254
Tested-by: Jenkins <ci@libreoffice.org>
Reviewed-by: Ashod Nakashian <ashnakash@gmail.com>
(cherry picked from commit 60e75fb276778459f6055360646d879b8c615d83)
Change-Id: I3332e393a88a5ed436316fa712ed920a4b37f4af
Reviewed-on: https://gerrit.libreoffice.org/26395
Tested-by: Jenkins <ci@libreoffice.org>
Reviewed-by: Michael Meeks <michael.meeks@collabora.com>
Diffstat (limited to 'include')
| -rw-r--r-- | include/comphelper/threadpool.hxx | 6 |
1 files changed, 6 insertions, 0 deletions
diff --git a/include/comphelper/threadpool.hxx b/include/comphelper/threadpool.hxx index cfa471b60802..2f726f0b406f 100644 --- a/include/comphelper/threadpool.hxx +++ b/include/comphelper/threadpool.hxx @@ -36,6 +36,12 @@ public: /// count for the CPU static ThreadPool& getSharedOptimalPool(); + /// returns a configurable max-concurrency + /// limit to avoid spawning an unnecessarily + /// large number of threads on high-core boxes. + /// MAX_CONCURRENCY envar controls the cap. + static sal_Int32 getPreferredConcurrency(); + ThreadPool( sal_Int32 nWorkers ); virtual ~ThreadPool(); |