On Wed, Apr 22, 2020 at 05:13:35PM -0600, Taylor Blau wrote: > From: Jeff King <peff@xxxxxxxx> > > Sometimes a bitmap traversal still has to walk some commits manually, > because those commits aren't included in the bitmap packfile (e.g., due > to a push or commit since the last full repack). If we're given an > object filter, we don't pass it down to this traversal. It's not > necessary for correctness because the bitmap code has its own filters to > post-process the bitmap result (which it must, to filter out the objects > that _are_ mentioned in the bitmapped packfile). > > And with blob filters, there was no performance reason to pass along > those filters, either. The fill-in traversal could omit them from the > result, but it wouldn't save us any time to do so, since we'd still have > to walk each tree entry to see if it's a blob or not. > > But now that we support tree filters, there's opportunity for savings. A > tree:depth=0 filter means we can avoid accessing trees entirely, since > we know we won't them (or any of the subtrees or blobs they point to). s/won't them/won't include them/ perhaps > diff --git a/t/perf/p5310-pack-bitmaps.sh b/t/perf/p5310-pack-bitmaps.sh > index b629a211f9..95379b1d4e 100755 > --- a/t/perf/p5310-pack-bitmaps.sh > +++ b/t/perf/p5310-pack-bitmaps.sh > @@ -95,4 +95,9 @@ test_perf 'pack to file (partial bitmap)' ' > git pack-objects --use-bitmap-index --all pack2b </dev/null >/dev/null > ' > > +test_perf 'rev-list with tree filter (partial bitmap)' ' > + git rev-list --use-bitmap-index --count --objects --all \ > + --filter=tree:0 >/dev/null > +' This covers perf testing of this partial-bitmap state, but we shoudl make sure that we are covering correctness, too. I think so, because t6113 creates a similar state for all of its tests. -Peff
