Jeff King <peff@xxxxxxxx> 于2022年12月9日周五 09:37写道： > > On Fri, Dec 09, 2022 at 01:49:18AM +0100, Michal Suchánek wrote: > > > > In this case it's the mtime on the object file (or the pack containing > > > it). But yes, it is far from a complete race-free solution. > > > > So if you are pushing a branch that happens to reuse commits or other > > objects from an earlier branh that might have been collected ín the > > meantime you are basically doomed. > > Basically yes. We do "freshen" the mtimes on object files when we omit > an object write (e.g., your index state ends up at the same tree as an > old one). But for a push, there is no freshening. We check the graph at > the time of the push and decide if we have everything we need (either > newly pushed, or from what we already had in the repo). And that is > what's racy; somebody might be deleting as that check is happening. > > > People deleting a branch and then pushing another variant in which many > > objects are the same is a risk. > > > > People exporting files from somewhere and adding them to the repo which > > are bit-identical when independently exported by multiple people and > > sometimes deleting branches is a risk. > > Yes, both of those are risky (along with many other variants). > I'm wondering if there's an easy and poor performance way to do gc safely? For example, add a file lock to the repository during git push and git gc? > -Peff
