Date: Sat, 22 Dec 2012 12:28:25 -0700 From: Ian Lepore <freebsd@damnhippie.dyndns.org> To: freebsd-arch@freebsd.org Cc: Jason Evans <jasone@freebsd.org> Subject: jemalloc enhancement for small-memory systems Message-ID: <1356204505.1129.21.camel@revolution.hippie.lan>
next in thread | raw e-mail | index | archive | help
When a daemon such as watchdogd uses mlockall(2) on a small-memory embedded system, it can end up wiring much of the available ram because jemalloc allocates large chunks of vmspace by default. More background info on this can be found in this thread: http://lists.freebsd.org/pipermail/freebsd-embedded/2012-November/001679.html It's hard to tune jemalloc's allocation behavior for this in a machine-independent way because the minimum chunk size depends on PAGE_SIZE and other factors internal to jemalloc. I've created a patch that addresses this by defining that lg_chunk:0 is implicitly a request to set the chunk size to the smallest value allowable for the machine it's running on. The patch is attached to this PR... http://www.freebsd.org/cgi/query-pr.cgi?pr=174641 Jason, could you please review this and consider incorporating it into jemalloc? Or let us know if there's a better way to handle this situation. -- Ian
Want to link to this message? Use this URL: <https://mail-archive.FreeBSD.org/cgi/mid.cgi?1356204505.1129.21.camel>