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| author | Eric Wong <e@80x24.org> | 2024-04-15 19:50:56 +0000 |
|---|---|---|
| committer | Eric Wong <e@80x24.org> | 2024-04-16 20:58:52 +0000 |
| commit | cd14eec87ae870f388ac24c2390e1c608fbed99c (patch) | |
| tree | 6b90aea9e7b4bf0225050066db8731db98e7c47d | |
| parent | 6543902ed6d596f86bdbe863c4d2a9c168b3f3df (diff) | |
| download | public-inbox-cd14eec87ae870f388ac24c2390e1c608fbed99c.tar.gz | |
Large string processing + concurrency + caching/memoization really brings out the worst in glibc malloc :<
| -rw-r--r-- | Documentation/public-inbox-tuning.pod | 5 | ||||
| -rw-r--r-- | examples/public-inbox-netd@.service | 5 |
2 files changed, 8 insertions, 2 deletions
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<MALLOC_MMAP_THRESHOLD_> to a lower +value (e.g. 131072) but that may require increasing the +C<sys.vm.max_map_count> sysctl. =head2 Other OS tuning knobs diff --git a/examples/public-inbox-netd@.service b/examples/public-inbox-netd@.service index 83d2e995..7437f086 100644 --- a/examples/public-inbox-netd@.service +++ b/examples/public-inbox-netd@.service @@ -12,8 +12,11 @@ Wants = public-inbox-netd.socket After = public-inbox-netd.socket [Service] -# An LD_PRELOAD for libjemalloc can be added here. It currently seems +# An LD_PRELOAD for libjemalloc can be added here. It is # more resistant to fragmentation in long-lived daemons than glibc. +# If you're unable to use jemalloc, setting MALLOC_MMAP_THRESHOLD_ +# to a lower value (e.g. 131072) but that may also require increasing +# the sys.vm.max_map_count sysctl. Environment = PI_CONFIG=/home/pi/.public-inbox/config \ PATH=/usr/local/bin:/usr/bin:/bin \ TZ=UTC \ |