On Mon, Oct 25, 2021 at 11:38:51AM -0400, Tom Lane wrote: > Andrew Dunstan <and...@dunslane.net> writes: > > On 10/25/21 10:23, Tom Lane wrote: > >> (Hmmm ... but disk space could > >> become a problem, particularly on older machines with not so much > >> disk. Do we really need to maintain a separate checkout for each > >> branch? It seems like a fresh checkout from the repo would be > >> little more expensive than the current copy-a-checkout process.) > > > If you set it up with these settings then the disk space used is minimal: > > git_use_workdirs => 1, > > rm_worktrees => 1, > > Maybe we should make those the defaults? AFAICS the current > default setup uses circa 200MB per back branch, even between runs. > I'm not sure what that is buying us.
Maybe git's shared/"alternates" would be helpful to minimize the size of .git/objects? I'm not sure - it looks like the BF client does its own stuff with symlinks. Is that for compatibility with old git ? https://github.com/PGBuildFarm/client-code/blob/main/PGBuild/SCM.pm If you "clone" a local location, it uses hard links by default. If you use --shared or --reference, then it uses references to the configured "alternates", if any. In both cases, .git/objects requires no additional space (but the "checked out" copy still takes up however much space). $ mkdir tmp $ git clone --quiet ./postgresql tmp/pg $ du -sh tmp/pg 492M tmp/pg $ rm -fr tmp/pg $ git clone --quiet --shared ./postgresql tmp/pg $ du -sh tmp/pg 124M tmp/pg -- Justin
