Re: [PATCH v2 06/10] preload-index.c: remove #ifdef NO_PTHREADS
From: Duy Nguyen <hidden>
Date: 2018-10-29 17:26:31
On Mon, Oct 29, 2018 at 6:21 PM Ben Peart [off-list ref] wrote:
quoted hunk ↗ jump to hunk
@@ -114,6 +104,9 @@ static void preload_index(struct index_state *index, threads = index->cache_nr / THREAD_COST; if ((index->cache_nr > 1) && (threads < 2) &&git_env_bool("GIT_TEST_PRELOAD_INDEX", 0)) threads = 2; + cpus = online_cpus(); + if (threads > cpus) + threads = cpus; if (threads < 2) return; trace_performance_enter();
Capping the number of threads to online_cpus() does not always make sense. In this case (or at least the original use case where we stat() over nfs) we want to issue as many requests to nfs server as possible to reduce latency and it has nothing to do with how many cores we have. Using more threads than cores might make sense since threads are blocked by nfs client, but we still want to send more to the server. -- Duy