| Message ID | 20200213021730.GC1126038@coredump.intra.peff.net (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | combining object filters and bitmaps | expand |
Jeff King <peff@peff.net> writes: > The "--use-bitmap-index" option is usually aspirational: if we have > bitmaps and the request can be fulfilled more quickly using them we'll > do so, but otherwise fall back to a non-bitmap traversal. > > The exception is object filtering, which explicitly dies if the two > options are combined. Let's convert this to the usual fallback behavior. > > This is a minor convenience for now (since the caller can easily know > that --filter and --use-bitmap-index don't combine), but will become > much more useful as we start to support _some_ filters with bitmaps, but > not others. Makes sense. Perhaps the option should have been called allow-bitmap-index or something along that line, but it is too late ;-) > +test_expect_success 'set up bitmapped repo' ' > + # one commit will have bitmaps, the other will not > + test_commit one && > + git repack -adb && > + test_commit two > +' > + > +test_expect_success 'filters fallback to non-bitmap traversal' ' > + # use a path-based filter, since they are inherently incompatible with > + # bitmaps (i.e., this test will never get confused by later code to > + # combine the features) > + filter=$(echo "!one" | git hash-object -w --stdin) && > + git rev-list --objects --filter=sparse:oid=$filter HEAD >expect && > + git rev-list --use-bitmap-index \ > + --objects --filter=sparse:oid=$filter HEAD >actual && > + test_cmp expect actual > +' OK.
On Thu, Feb 13, 2020 at 10:19:19AM -0800, Junio C Hamano wrote: > Jeff King <peff@peff.net> writes: > > > The "--use-bitmap-index" option is usually aspirational: if we have > > bitmaps and the request can be fulfilled more quickly using them we'll > > do so, but otherwise fall back to a non-bitmap traversal. > > > > The exception is object filtering, which explicitly dies if the two > > options are combined. Let's convert this to the usual fallback behavior. > > > > This is a minor convenience for now (since the caller can easily know > > that --filter and --use-bitmap-index don't combine), but will become > > much more useful as we start to support _some_ filters with bitmaps, but > > not others. > > Makes sense. > > Perhaps the option should have been called allow-bitmap-index or > something along that line, but it is too late ;-) Yeah. It's also annoyingly long to type, and makes for long lines in the test scripts. ;) There are also some weird semantics with the fallback, because the output may differ depending on whether we use bitmaps (see one of the later patches). I wouldn't be opposed to cleaning this up and giving it a new option ("--allow-bitmaps" or something) to keep compatibility, but it's out of scope here. The existing option (and my suggestion, as well as most of the internal code) are guilty of equating "bitmap" with "object reachability bitmap". There's lots of things one might use bitmaps for, and at some point we might even expose such a thing via rev-list. Anyway, that concludes my rant. I don't think any of these are urgent to fix, and definitely shouldn't be part of this series. -Peff
diff --git a/builtin/rev-list.c b/builtin/rev-list.c index e28d62ec64..bce406bd1e 100644 --- a/builtin/rev-list.c +++ b/builtin/rev-list.c @@ -521,8 +521,8 @@ int cmd_rev_list(int argc, const char **argv, const char *prefix) if (revs.show_notes) die(_("rev-list does not support display of notes")); - if (filter_options.choice && use_bitmap_index) - die(_("cannot combine --use-bitmap-index with object filtering")); + if (filter_options.choice) + use_bitmap_index = 0; save_commit_buffer = (revs.verbose_header || revs.grep_filter.pattern_list || diff --git a/t/t6113-rev-list-bitmap-filters.sh b/t/t6113-rev-list-bitmap-filters.sh new file mode 100755 index 0000000000..977f8d0930 --- /dev/null +++ b/t/t6113-rev-list-bitmap-filters.sh @@ -0,0 +1,24 @@ +#!/bin/sh + +test_description='rev-list combining bitmaps and filters' +. ./test-lib.sh + +test_expect_success 'set up bitmapped repo' ' + # one commit will have bitmaps, the other will not + test_commit one && + git repack -adb && + test_commit two +' + +test_expect_success 'filters fallback to non-bitmap traversal' ' + # use a path-based filter, since they are inherently incompatible with + # bitmaps (i.e., this test will never get confused by later code to + # combine the features) + filter=$(echo "!one" | git hash-object -w --stdin) && + git rev-list --objects --filter=sparse:oid=$filter HEAD >expect && + git rev-list --use-bitmap-index \ + --objects --filter=sparse:oid=$filter HEAD >actual && + test_cmp expect actual +' + +test_done
The "--use-bitmap-index" option is usually aspirational: if we have bitmaps and the request can be fulfilled more quickly using them we'll do so, but otherwise fall back to a non-bitmap traversal. The exception is object filtering, which explicitly dies if the two options are combined. Let's convert this to the usual fallback behavior. This is a minor convenience for now (since the caller can easily know that --filter and --use-bitmap-index don't combine), but will become much more useful as we start to support _some_ filters with bitmaps, but not others. The test infrastructure here is bigger than necessary for checking this one small feature. But it will serve as the basis for more filtering bitmap tests in future patches. Signed-off-by: Jeff King <peff@peff.net> --- builtin/rev-list.c | 4 ++-- t/t6113-rev-list-bitmap-filters.sh | 24 ++++++++++++++++++++++++ 2 files changed, 26 insertions(+), 2 deletions(-) create mode 100755 t/t6113-rev-list-bitmap-filters.sh