Ævar Arnfjörð Bjarmason <avarab@xxxxxxxxx> 于2021年7月25日周日 上午5:23写道： > > > On Sat, Jul 24 2021, ZheNing Hu wrote: > > > After reusing ref-filter logic for cat-file --batch, the function of > > cat-file --batch has been enhanced, > > but the performance of cat-file is severely degraded. So we need a > > better solution to solve it. > > its last version is here: > > https://lore.kernel.org/git/pull.993.v2.git.1626363626.gitgitgadget@xxxxxxxxx/ > > > > Use google doc to show some of my recent ideas: > > https://docs.google.com/document/d/1hyM-ecMd8C_TJ3OsOn46nMr8ZxCUxeK7HKj-bRkq3sk/edit?usp=sharing > > > > Anyone is welcome to comment and suggest better solutions! > > Having looked at that Google Doc it seems to just discuss "Plan A", or > there some multi-doc magic and there's a "Plan B", or...? I'm not very > familiar with Google Docs. > There may be several plan that have not been written to it for the time being. > Anyway, I'd encourage you to just send this as an E-Mail to the mailing > list. > Ok, I can migrate them here. > Having skimmed it I'm a bit confused about this in reference to > performance generally. I haven't looked into the case you're discussing, > but as I noted in > https://lore.kernel.org/git/87im1p6x34.fsf@xxxxxxxxxxxxxxxxxxx/ the > profiling clearly shows that the main problem is that you've added > object lookups we skipped before. > Yeah, you showed me last time that lookup_object() took up a lot of time. > I think any plan to improve performance should start with a perf test, > see which of your patches have performance regressions, if some don't > and are otherwise OK perhaps those can go in earlier. > Makes sense. Last time the test performance of commits is here: https://lore.kernel.org/git/CAOLTT8RR4+tUuT2yc2PDL9NwCburW8bM_Sht6nhKJ_fYV8fGsQ@xxxxxxxxxxxxxx/ The main commit with performance degradation is "[GSOC] cat-file: reuse ref-filter logic", we need to focus on it. > Then we'll have the smallest possible set of changes that's correct, but > introduces performance regressions, and can look at what those are doing > to slow things down... Ok. Thanks. -- ZheNing Hu
