From: Junio C Hamano Date: Tue, 10 Sep 2019 01:09:51 GMT Subject: Re: [PATCH v2] cache-tree: do not lazy-fetch merge tree Message-ID: In-Reply-To: <20190909222101.GB31319@sigill.intra.peff.net> Jeff King writes: > I wondered also if this means we should be using OBJECT_INFO_QUICK. > I.e., do we expect to see a "miss" here often, forcing us to re-scan the > packed directory? As a performance optimization hack, it is OK if we did not notice that the tree object, which corresponds to what is currently prepared for a directory in the index, does exist in the object store. It is not worth rescanning the packs to "protect" against races, I think, in the "repair" codepath. When the user actually wants to write the index out as a tree, we would write it out as a loose object (or omit doing so if we know there are already copies), but because it is not a crime to create a duplicate loose object when we already have a packed copy, I do not think we need to rescan in that context, either. But I do not think the codepath Jonathan's patch touches is about that operation.