From: Thomas Gummerer Date: Sun, 14 Oct 2018 09:59:49 GMT Subject: Re: Does git load index file into memory? Message-ID: <20181014095949.GB22611@hank.intra.tgummerer.com> In-Reply-To: On 10/12, Farhan Khan wrote: > Hi all, > > Does git load the entire index file into memory when it wants to > edit/view it? I ask because I wonder if this can become a problem with > the index file becomes arbitrarily large, like for the Linux kernel. Yes, currently git always loads the entire index file for any operation on it. This is not particularly a problem for projects like the linux kernel, as the index file for it is relatively small, ~6MB at the moment. It is more of a problem for larger repositories, such as the windows repository, which has and index file of ~300-400MB, iirc, where loading the index has a significant cost. There's some patch series in progress to improve the performance, e.g. Ben Pearts series to load the index in parallel [*1*]. For writing the index to disk again, the split index feature can help improve performance. See also 'man git-update-index' and "core.splitIndex" in 'man git-config'. [*1*]: https://public-inbox.org/git/20181010155938.20996-1-peartben@gmail.com/ > Thanks, > -- > Farhan Khan > PGP Fingerprint: B28D 2726 E2BC A97E 3854 5ABE 9A9F 00BC D525 16EE