RE: cherry-pick very slow on big repository

[Kevin Willford <kewillf@microsoft.com>]

Since this is happening during a merge, you might need to use merge.renameLimit
or the merge strategy option of -Xno-renames.  Although the code does fallback
to use the diff.renameLimit but there is still a lot that is done before even checking
the rename limit so I would first try getting renames turned off.

Thanks,
Kevin

> -----Original Message-----
> From: git-owner@vger.kernel.org [mailto:git-owner@vger.kernel.org] On Behalf
> Of Peter Krefting
> Sent: Friday, November 10, 2017 7:05 AM
> To: Derrick Stolee <stolee@gmail.com>
> Cc: Jeff King <peff@peff.net>; Git Mailing List <git@vger.kernel.org>
> Subject: Re: cherry-pick very slow on big repository
> 
> Derrick Stolee:
> 
> > Git is spending time detecting renames, which implies you probably
> > renamed a folder or added and deleted a large number of files. This
> > rename detection is quadratic (# adds times # deletes).
> 
> Yes, a couple of directories with a lot of template files have been
> renamed (and some removed, some added) between the current development
> branch and this old maintenance branch. I get the "Performing inexact
> rename detection" a lot when merging changes in the other direction.
> 
> However, none of them applies to these particular commits, which only
> touches files that are in the exact same location on both branches.
> 
> > You can remove this rename detection by running your cherry-pick
> > with `git -c diff.renameLimit=1 cherry-pick ...`
> 
> That didn't work, actually it failed to finish with this setting in
> effect, it hangs in such a way that I can't stop it with Ctrl+C
> (neither when running from the command line, nor when running inside
> gdb). It didn't finish in the 20 minutes I gave it.
> 
> I also tried with diff.renames=false, which also seemed to fail.
> 
> --
> \\// Peter -
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