From a7b0a124c3ebe505cfd8c2d5cc797b8f0c96fbc6 Mon Sep 17 00:00:00 2001 From: Edward Tomasz Napierala Date: Fri, 30 Nov 2018 13:57:49 +0000 Subject: [PATCH] Mention different mmap(2) behaviour with retain:true. --- doc/jemalloc.xml.in | 3 +++ 1 file changed, 3 insertions(+) diff --git a/doc/jemalloc.xml.in b/doc/jemalloc.xml.in index 058e9db9..a73f0ad7 100644 --- a/doc/jemalloc.xml.in +++ b/doc/jemalloc.xml.in @@ -944,6 +944,9 @@ mallctl("arena." STRINGIFY(MALLCTL_ARENAS_ALL) ".decay", munmap 2 or equivalent (see stats.retained for related details). + It also makes jemalloc use + mmap2 + in a more greedy way, mapping larger chunks in one go. This option is disabled by default unless discarding virtual memory is known to trigger platform-specific performance problems, e.g. for [64-bit] Linux, which