Re: [patch 2/2] Documentation/process: Add tip tree handbook

From: Greg KH
Date: Thu Nov 08 2018 - 17:33:38 EST


On Thu, Nov 08, 2018 at 05:19:47PM -0500, Theodore Y. Ts'o wrote:
> On Thu, Nov 08, 2018 at 01:04:49PM -0800, Greg KH wrote:
> > > (Also note that even with fast SSD's and/or everything in page cache,
> > > runnning "tag --contains <COMMITID>" will take a good 3-4 seconds, and
> > > if the git packs are not in the page cache, and/or you're unfortunate
> > > enough to have your git trees on an HDD.... it's not pretty.)
> >
> > I recommend the "static cache" or whatever that thing is called, that
> > helps out a _LOT_ with stuff like this. For the kernel tree, which is
> > never rebased, it speeds up this so much.
>
> At the risk of asking a stupid question, which cache is this? I don't
> think it's the untrackedCache; is it the BitmapHashCache?

It's the 'commitGraph', here's the article I was trying to remember I
learned this from:
https://blogs.msdn.microsoft.com/devops/2018/06/25/supercharging-the-git-commit-graph/

greg k-h