> On 9/3/2019 3:42 PM, Jonathan Tan wrote: > > When cherry-picking (for example), new trees may be constructed. During > > this process, Git checks whether these trees exist. However, in a > > partial clone, this causes a lazy fetch to occur, which is both > > unnecessary (because Git has already constructed this tree as part of > > the cherry-picking process) and likely to fail (because the remote > > probably doesn't have this tree). > > If we have constructed the object already, then why do we not see it > and avoid fetching it? This must be a slightly strange timing issue > with objects being flushed to disk or added to the object cache.
Thanks for taking a look at this! The answer is that I wasn't precise when I said "already constructed" - I meant that it is in a struct strbuf. It hasn't been written to disk yet, so has_object_file() does not see it. > One approach is to find all of these has_object_file() calls that should > really be one with OBJECT_INFO_SKIP_FETCH_OBJECT. Another would be to > find out why has_object_file() isn't seeing the object we constructed. By the former, do you mean that we should look at the other has_object_file() calls? I looked at the others in cache-tree.c and I think the one in this patch is the only one that is called on an OID generated from hash_object_file(). (And I answered the latter in the above paragraph.) To avoid confusion, maybe this commit message is better: When cherry-picking (for example), new trees may be constructed. During this process, Git constructs the new tree in a struct strbuf, computes the OID of the new tree, and checks if the new OID already exists on disk. However, in a partial clone, the disk check causes a lazy fetch to occur, which is both unnecessary (because we have the tree in the struct strbuf) and likely to fail (because the remote probably doesn't have this tree).
