hg runs out of ram, fails

[Matt Mackall]

On Fri, Apr 14, 2006 at 12:16:06PM -0400, Jeremy Andrews wrote:

> One of the things I've been using Mercurial for is to backup some of
> my important files. It's worked fine until today when I tried to
> push an updated sync to my backup server. The hg process quickly
> consumes all available ram, then fails with the following errors.
> There's very little changed between today's sync and yesterday's
> sync, primarily the addition of a 383 MB bzip2 compressed MySQL
> database dump.

Am I understanding correctly that you've checked in a 383MB file?

If so, the result is not surprising. From the FAQ:

 Mercurial currently assumes that single files, indices, and manifests
 can fit in memory for efficiency.

Operations like delta calculation will in fact require a small
multiple of the file size. So it's easy to imagine running out of
memory here. You may be able to get past the problem by adding a
couple gigs of swap, but..

>   File "/usr/lib/python2.4/site-packages/mercurial/changegroup.py", line 40, in genchunk
>     return "%s%s" % (header, data)
> MemoryError

We should probably catch that one.

-- 
Mathematics is the supreme nostalgia of our time.