Re: [PATCH 0/6] Speed up mirror-fetches with many refs

From: Derrick Stolee <stolee@gmail.com>
Date: Aug 20, 2021, 14:50 UTC
Message-ID: <857d18a1-97b2-b7a6-64d4-4b31daf79e64@gmail.com>
In-Reply-To: <cover.1629452412.git.ps@pks.im>

On 8/20/2021 6:08 AM, Patrick Steinhardt wrote: ...

> As it turns out, many of the issues are again caused by loading and
> dereferencing refs. This patch series thus mostly focusses on optimizing
> the patterns there, where the biggest win is to opportunistically load
> refs via commit-graphs.

You caught my attention at "commit-graph" and I found your use of them to be interesting. You strike a balance in checking the commit-graph when it is likely to be helpful, and skip the commit-graph when it is not. (For example, PATCH 2 is unlikely to benefit from checking the commit-graph at that point, because we are looking for objects that were just downloaded.)

I read all the patches and checked the full context of the functions to see if there were any issues, but found none. My only comments are about the case of many annotated tags (do we slow down?) and some nitpicks.

Thanks, -Stolee