From cd14eec87ae870f388ac24c2390e1c608fbed99c Mon Sep 17 00:00:00 2001 From: Eric Wong Date: Mon, 15 Apr 2024 19:50:56 +0000 Subject: doc: note MALLOC_MMAP_THRESHOLD_ as a potential workaround Large string processing + concurrency + caching/memoization really brings out the worst in glibc malloc :< --- Documentation/public-inbox-tuning.pod | 5 ++++- 1 file changed, 4 insertions(+), 1 deletion(-) (limited to 'Documentation') diff --git a/Documentation/public-inbox-tuning.pod b/Documentation/public-inbox-tuning.pod index 73246144..7d0690b4 100644 --- a/Documentation/public-inbox-tuning.pod +++ b/Documentation/public-inbox-tuning.pod @@ -165,8 +165,11 @@ capacity planning. Bursts of small object allocations late in process life contribute to fragmentation of the heap due to arenas (slabs) used internally by Perl. -jemalloc (tested as an LD_PRELOAD on GNU/Linux) appears to reduce +jemalloc (tested as an LD_PRELOAD on GNU/Linux) reduces overall fragmentation compared to glibc malloc in long-lived processes. +glibc malloc users may try setting C to a lower +value (e.g. 131072) but that may require increasing the +C sysctl. =head2 Other OS tuning knobs -- cgit v1.2.3-24-ge0c7