Re: pack operation is thrashing my server

Ken Pratt [off-list ref] wrote:

I'm having memory issues when trying to clone a remote git repository.

The remote repository is bare, and is 180MB in size (says du), with
1824 objects. The remote (VPS) server is running git version 1.5.6.4
on Arch Linux on a x86_64 Opteron with 256MB of dedicated RAM.

PID USER      PR  NI  VIRT  RES  SHR S %CPU %MEM    TIME+  COMMAND
21782 kenpratt  20   0  444m 212m  272 D    3 83.0   0:04.98 git-pack-object

Well, clearly the server is swapping at this point.  212m resident
for this git-pack-objects process leaves no room available for
anything else.  Git is using too much memory for this system.
 

I've tried very conservative pack settings:

[pack]
        threads = 1
        windowmemory = 64M
        deltacachesize = 1M
        deltacachelimit = 1M

Have you tried something like this?

	[core]
		packedGitWindowSize = 16m
		packedGitLimit = 64m

	[pack]
		threads = 1
		windowMemory = 64m
		deltaCacheSize = 1m

On a 64 bit system packedGitWindowSize and packedGitLimit have very
large thresholds which will cause it to mmap in the entire pack file.
You may need to try even smaller settings than these; 256m physical
memory isn't a lot when dealing with a repository 180m in size.
Especially on a 64 bit system.

-- 
Shawn.