Subject: Re: git-repack keeps running out of memory

From: Junio C Hamano <[email-masked]>
Date: Mon, 01 Jun 2015 11:43:01 -0700

Phil Susi <[email-masked]> writes:

> I keep having git-repack run out of virtual memory ( 32 bit system )
> when trying to repack my linux kernel repo.  It keeps making it right
> up to 99% then barfing saying mmap failed: Cannot allocate memory.
>
> I thought I could help this by limiting the pack size, and using
> --window-memory to limit the memory usage, but it still happens with
> this full command line:
>
> git repack -a -d --max-pack-size=500m -f -F --depth=20 --window=250
> --window-memory=500m
>
> The key factor seems to be the --window... with 50 it works fine, but
> with 100 or more, even with the very low --window-memory limit, it
> crashes.

Unfortunately, that is totally expected.  Window tells us to keep
enough information to compare with that many objects in-core.  I do
not think max-pack-size would affect much.