From 12f7257b8f6ba0de1fb05b598e916c8b14bcab8c Mon Sep 17 00:00:00 2001 From: Tim Ruffing Date: Wed, 20 Sep 2023 17:12:24 +0000 Subject: [PATCH] doc: Be vague instead of wrong about MALLOC_ARENA_MAX Before this commit, we claim that glibc's malloc implementation uses 2 arenas by default. But that's true only on 32-bit systems, and even there, it uses *up* to 2 arenas. This commit fixes the wrong statement. The new statement is intentionally vague to reduce our maintenance burden. For details, see: https://www.gnu.org/software/libc/manual/html_node/Memory-Allocation-Tunables.html#index-glibc_002emalloc_002earena_005fmax Noticed in: https://github.com/bitcoin/bitcoin/pull/27642#issuecomment-1728103427 --- doc/reduce-memory.md | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/doc/reduce-memory.md b/doc/reduce-memory.md index dbe88d45f32..2710797ef3a 100644 --- a/doc/reduce-memory.md +++ b/doc/reduce-memory.md @@ -43,7 +43,7 @@ threads take up 8MiB for the thread stack on a 64-bit system, and 4MiB in a ## Linux specific -By default, glibc will create up to two heap arenas per core. This is known to cause excessive memory usage in some scenarios. To avoid this make a script that sets `MALLOC_ARENA_MAX` before starting bitcoind: +By default, glibc's implementation of `malloc` may use more than one arena. This is known to cause excessive memory usage in some scenarios. To avoid this, make a script that sets `MALLOC_ARENA_MAX` before starting bitcoind: ```bash #!/usr/bin/env bash