Re: [PATCH] Speedup recursive by flushing index only once for all entries

From: Linus Torvalds <torvalds@osdl.org>
Date: Jan 11, 2007, 22:28 UTC
Message-ID: <Pine.LNX.4.64.0701111424400.3594@woody.osdl.org>
In-Reply-To: <20070111221053.GD6058@steel.home>

On Thu, 11 Jan 2007, Alex Riesen wrote:

> 
> It must have been large leak, as I really have seen the memory usage
> dropping down significantly.

I really think it was about 6MB (or whatever your index file size was) per every single resolved file. I think merge-recursive used to flush the index file every time it resolved something, and every flush would basically leak the whole buffer used to write the index.

Anyway, 40-50 sec on a fairly weak laptop for a 44k-file merge sounds like git doesn't have to be totally embarrassed. I'm not saying we shouldn't be able to do it faster, but it's at least _possible_ that a lot of the time spent is now spent doing real work (ie maybe you actually have a fair amount of file-level merging? Maybe it's 40-50 sec because there's some amount of real IO going on, and a fair amount of real work done too?)

			Linus