Commit Graph

258 Commits

Author SHA1 Message Date
Junio C Hamano
58840e62a4 Merge branch 'ps/pack-bitmap-optim'
Optimize "rev-list --use-bitmap-index --objects" corner case that
uses negative tags as the stopping points.

* ps/pack-bitmap-optim:
  pack-bitmap: avoid traversal of objects referenced by uninteresting tag
2021-04-07 16:54:09 -07:00
Junio C Hamano
858119f6d7 Merge branch 'nk/diff-index-fsmonitor'
"git diff-index" codepath has been taught to trust fsmonitor status
to reduce number of lstat() calls.

* nk/diff-index-fsmonitor:
  fsmonitor: add perf test for git diff HEAD
  fsmonitor: add assertion that fsmonitor is valid to check_removed
  fsmonitor: skip lstat deletion check during git diff-index
2021-03-24 14:36:27 -07:00
Junio C Hamano
2744383cbd Merge branch 'tb/geometric-repack'
"git repack" so far has been only capable of repacking everything
under the sun into a single pack (or split by size).  A cleverer
strategy to reduce the cost of repacking a repository has been
introduced.

* tb/geometric-repack:
  builtin/pack-objects.c: ignore missing links with --stdin-packs
  builtin/repack.c: reword comment around pack-objects flags
  builtin/repack.c: be more conservative with unsigned overflows
  builtin/repack.c: assign pack split later
  t7703: test --geometric repack with loose objects
  builtin/repack.c: do not repack single packs with --geometric
  builtin/repack.c: add '--geometric' option
  packfile: add kept-pack cache for find_kept_pack_entry()
  builtin/pack-objects.c: rewrite honor-pack-keep logic
  p5303: measure time to repack with keep
  p5303: add missing &&-chains
  builtin/pack-objects.c: add '--stdin-packs' option
  revision: learn '--no-kept-objects'
  packfile: introduce 'find_kept_pack_entry()'
2021-03-24 14:36:27 -07:00
Junio C Hamano
e8d5a423ca Merge branch 'jk/perf-in-worktrees'
Perf test update to work better in secondary worktrees.

* jk/perf-in-worktrees:
  t/perf: avoid copying worktree files from test repo
  t/perf: handle worktrees as test repos
2021-03-22 14:00:23 -07:00
Patrick Steinhardt
540cdc11ad pack-bitmap: avoid traversal of objects referenced by uninteresting tag
When preparing the bitmap walk, we first establish the set of of have
and want objects by iterating over the set of pending objects: if an
object is marked as uninteresting, it's declared as an object we already
have, otherwise as an object we want. These two sets are then used to
compute which transitively referenced objects we need to obtain.

One special case here are tag objects: when a tag is requested, we
resolve it to its first not-tag object and add both resolved objects as
well as the tag itself into either the have or want set. Given that the
uninteresting-property always propagates to referenced objects, it is
clear that if the tag is uninteresting, so are its children and vice
versa. But we fail to propagate the flag, which effectively means that
referenced objects will always be interesting except for the case where
they have already been marked as uninteresting explicitly.

This mislabeling does not impact correctness: we now have it in our
"wants" set, and given that we later do an `AND NOT` of the bitmaps of
"wants" and "haves" sets it is clear that the result must be the same.
But we now start to needlessly traverse the tag's referenced objects in
case it is uninteresting, even though we know that each referenced
object will be uninteresting anyway. In the worst case, this can lead to
a complete graph walk just to establish that we do not care for any
object.

Fix the issue by propagating the `UNINTERESTING` flag to pointees of tag
objects and add a benchmark with negative revisions to p5310. This shows
some nice performance benefits, tested with linux.git:

Test                                                          HEAD~                  HEAD
---------------------------------------------------------------------------------------------------------------
5310.3: repack to disk                                        193.18(181.46+16.42)   194.61(183.41+15.83) +0.7%
5310.4: simulated clone                                       25.93(24.88+1.05)      25.81(24.73+1.08) -0.5%
5310.5: simulated fetch                                       2.64(5.30+0.69)        2.59(5.16+0.65) -1.9%
5310.6: pack to file (bitmap)                                 58.75(57.56+6.30)      58.29(57.61+5.73) -0.8%
5310.7: rev-list (commits)                                    1.45(1.18+0.26)        1.46(1.22+0.24) +0.7%
5310.8: rev-list (objects)                                    15.35(14.22+1.13)      15.30(14.23+1.07) -0.3%
5310.9: rev-list with tag negated via --not --all (objects)   22.49(20.93+1.56)      0.11(0.09+0.01) -99.5%
5310.10: rev-list with negative tag (objects)                 0.61(0.44+0.16)        0.51(0.35+0.16) -16.4%
5310.11: rev-list count with blob:none                        12.15(11.19+0.96)      12.18(11.19+0.99) +0.2%
5310.12: rev-list count with blob:limit=1k                    17.77(15.71+2.06)      17.75(15.63+2.12) -0.1%
5310.13: rev-list count with tree:0                           1.69(1.31+0.38)        1.68(1.28+0.39) -0.6%
5310.14: simulated partial clone                              20.14(19.15+0.98)      19.98(18.93+1.05) -0.8%
5310.16: clone (partial bitmap)                               12.78(13.89+1.07)      12.72(13.99+1.01) -0.5%
5310.17: pack to file (partial bitmap)                        42.07(45.44+2.72)      41.44(44.66+2.80) -1.5%
5310.18: rev-list with tree filter (partial bitmap)           0.44(0.29+0.15)        0.46(0.32+0.14) +4.5%

While most benchmarks are probably in the range of noise, the newly
added 5310.9 and 5310.10 benchmarks consistenly perform better.

Signed-off-by: Patrick Steinhardt <ps@pks.im>.
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2021-03-22 12:10:56 -07:00
Nipunn Koorapati
7e5aa13d2c fsmonitor: add perf test for git diff HEAD
Update the xargs call so that if your large repo contains
symlinks, test-tool chmtime failure does not end the script.

On Linux
Test                                                          this tree           upstream/master
---------------------------------------------------------------------------------------------------------
7519.4: status (fsmonitor=fsmonitor-watchman)                 0.52(0.43+0.10)     0.53(0.49+0.05) +1.9%
7519.5: status -uno (fsmonitor=fsmonitor-watchman)            0.21(0.15+0.07)     0.22(0.13+0.09) +4.8%
7519.6: status -uall (fsmonitor=fsmonitor-watchman)           1.65(0.93+0.71)     1.69(1.03+0.65) +2.4%
7519.7: status (dirty) (fsmonitor=fsmonitor-watchman)         11.99(11.34+1.58)   11.95(11.02+1.79) -0.3%
7519.8: diff (fsmonitor=fsmonitor-watchman)                   0.25(0.17+0.26)     0.25(0.18+0.26) +0.0%
7519.9: diff HEAD (fsmonitor=fsmonitor-watchman)              0.39(0.25+0.34)     0.89(0.35+0.74) +128.2%
7519.10: diff -- 0_files (fsmonitor=fsmonitor-watchman)       0.16(0.13+0.04)     0.16(0.12+0.05) +0.0%
7519.11: diff -- 10_files (fsmonitor=fsmonitor-watchman)      0.16(0.12+0.05)     0.16(0.12+0.05) +0.0%
7519.12: diff -- 100_files (fsmonitor=fsmonitor-watchman)     0.16(0.12+0.05)     0.16(0.12+0.05) +0.0%
7519.13: diff -- 1000_files (fsmonitor=fsmonitor-watchman)    0.16(0.11+0.06)     0.16(0.12+0.05) +0.0%
7519.14: diff -- 10000_files (fsmonitor=fsmonitor-watchman)   0.18(0.13+0.06)     0.17(0.10+0.08) -5.6%
7519.15: add (fsmonitor=fsmonitor-watchman)                   2.25(1.53+0.68)     2.25(1.47+0.74) +0.0%
7519.18: status (fsmonitor=disabled)                          0.88(0.73+1.03)     0.89(0.67+1.08) +1.1%
7519.19: status -uno (fsmonitor=disabled)                     0.45(0.43+0.89)     0.45(0.34+0.98) +0.0%
7519.20: status -uall (fsmonitor=disabled)                    1.88(1.16+1.58)     1.88(1.22+1.51) +0.0%
7519.21: status (dirty) (fsmonitor=disabled)                  7.53(7.05+2.11)     7.53(6.98+2.04) +0.0%
7519.22: diff (fsmonitor=disabled)                            0.42(0.37+0.92)     0.42(0.38+0.91) +0.0%
7519.23: diff HEAD (fsmonitor=disabled)                       0.44(0.41+0.90)     0.44(0.40+0.91) +0.0%
7519.24: diff -- 0_files (fsmonitor=disabled)                 0.13(0.09+0.05)     0.13(0.09+0.05) +0.0%
7519.25: diff -- 10_files (fsmonitor=disabled)                0.13(0.10+0.04)     0.13(0.10+0.04) +0.0%
7519.26: diff -- 100_files (fsmonitor=disabled)               0.13(0.09+0.05)     0.13(0.10+0.04) +0.0%
7519.27: diff -- 1000_files (fsmonitor=disabled)              0.13(0.09+0.06)     0.13(0.09+0.05) +0.0%
7519.28: diff -- 10000_files (fsmonitor=disabled)             0.14(0.11+0.05)     0.14(0.10+0.05) +0.0%
7519.29: add (fsmonitor=disabled)                             2.43(1.61+1.64)     2.43(1.69+1.57) +0.0%

On linux (2.29.2 vs w/ this patch):
nipunn@nipunn-dbx:~/src/server3$ strace -f -c git diff 2>&1 | grep lstat
  0.04    0.000063           3        20         6 lstat
nipunn@nipunn-dbx:~/src/server3$ strace -f -c git diff HEAD 2>&1 | grep lstat
 94.98    5.242262          10    523783        13 lstat
nipunn@nipunn-dbx:~/src/server3$ strace -f -c ../git/bin-wrappers/git diff 2>&1 | grep lstat
  0.38    0.000032           5         7         3 lstat
nipunn@nipunn-dbx:~/src/server3$ strace -f -c ../git/bin-wrappers/git diff HEAD 2>&1 | grep lstat
 99.44    0.741892           9     81634        10 lstat

On mac (2.29.2 vs w/ this patch):
nipunn-mbp:server nipunn$ sudo dtruss -L -f -c git diff 2>&1 | grep "^lstat64 "
lstat64                                         8
nipunn-mbp:server nipunn$ sudo dtruss -L -f -c git diff HEAD 2>&1 | grep "^lstat64 "
lstat64                                    120242
nipunn-mbp:server nipunn$ sudo dtruss -L -f -c ../git/bin-wrappers/git diff 2>&1 | grep "^lstat64 "
lstat64                                         4
nipunn-mbp:server nipunn$ sudo dtruss -L -f -c ../git/bin-wrappers/git diff HEAD 2>&1 | grep "^lstat64 "
lstat64                                      4497

There are still a bunch of lstats - on directories, but not every file. Progress!

Signed-off-by: Nipunn Koorapati <nipunn@dropbox.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2021-03-18 13:31:14 -07:00
Junio C Hamano
700696bcfc Merge branch 'jh/fsmonitor-prework'
Preliminary changes to fsmonitor integration.

* jh/fsmonitor-prework:
  fsmonitor: refactor initialization of fsmonitor_last_update token
  fsmonitor: allow all entries for a folder to be invalidated
  fsmonitor: log FSMN token when reading and writing the index
  fsmonitor: log invocation of FSMonitor hook to trace2
  read-cache: log the number of scanned files to trace2
  read-cache: log the number of lstat calls to trace2
  preload-index: log the number of lstat calls to trace2
  p7519: add trace logging during perf test
  p7519: move watchman cleanup earlier in the test
  p7519: fix watchman watch-list test on Windows
  p7519: do not rely on "xargs -d" in test
2021-03-01 14:02:56 -08:00
Jeff King
36e834abc1 t/perf: avoid copying worktree files from test repo
When running the perf suite, we copy files from an existing $GIT_DIR to
a scratch repository to give us a realistic setup on which to operate.
Since the perf scripts themselves may modify the scratch repository, we
want to make sure we've scrubbed any references back to the original.

One existing example is that we avoid copying the file "commondir" at
the top-level of the repository. In a worktree git-dir (e.g.,
.git/worktrees/foo), that file contains the path to the parent
repository; copying it could mean ref updates in the scratch repository
affect the original.

But there are other files we should cover, too:

  - "gitdir" in a worktree git-dir contains the path to the actual .git
    file in the working tree. We _shouldn't_ end up looking at it at
    all, since the lack of a "commondir" file means Git won't consider
    this to be a worktree git-dir. But it's best to err on the safe
    side.

  - in a parent repository that contains worktrees, the
    "$GIT_DIR/worktrees" directory will contain the git dirs for the
    individual worktrees. Which will themselves contain commondir and
    gitdir files that may reference the original repository. We should
    likewise remove them.

    Note that this does mean that the perf suite's scratch repositories
    will never have any worktrees. That's OK; we don't have any perf tests
    that are influenced by their presence. If we add any, they'd
    probably want to create the worktrees themselves anyway.

This patch adds both paths to the set of omissions in
test_perf_copy_repo_contents(). Note that we won't get confused here by
matching arbitrary names like refs/heads/commondir. This list is always
matching top-level entries in $GIT_DIR (we rely on "cp -R" to do the
actual recursion).

Suggested-by: Johannes Schindelin <Johannes.Schindelin@gmx.de>
Signed-off-by: Jeff King <peff@peff.net>
Reviewed-by: Derrick Stolee <dstolee@microsoft.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2021-02-26 14:21:04 -08:00
Jeff King
85b87a5396 t/perf: handle worktrees as test repos
The perf suite gets confused when test_perf_default_repo is pointed at a
worktree (which includes when it is run from within a worktree at all,
since the default is to use the current repository).

Here's an example:

  $ git worktree add ~/foo
  Preparing worktree (new branch 'foo')
  HEAD is now at 328c109303 The eighth batch
  $ cd ~/foo
  $ make
  [...build output...]
  $ cd t/perf
  $ ./p0000-perf-lib-sanity.sh -v -i
  [...]
  perf 1 - test_perf_default_repo works:
  running:
  	foo=$(git rev-parse HEAD) &&
  	test_export foo

  fatal: ambiguous argument 'HEAD': unknown revision or path not in the working tree.
  Use '--' to separate paths from revisions, like this:
  'git <command> [<revision>...] -- [<file>...]'

The problem is that we didn't copy all of the necessary files from the
source repository (in this case we got HEAD, but we have no refs!). We
discover the git-dir with "rev-parse --git-dir", but this points to the
worktree's partial repository in .../.git/worktrees/foo.

That partial repository has a "commondir" file which points to the main
repository, where the actual refs are stored, but we don't copy it. This
is the correct thing to do, though! If we did copy it, then our scratch
test repo would be pointing back to the original main repo, and any ref
updates we made in the tests would impact that original repo.

Instead, we need to either:

  1. Make a scratch copy of the original main repo (in addition to the
     worktree repo), and point the scratch worktree repo's commondir at
     it. This preserves the original relationship, but it's doubtful any
     script really cares (if they are testing worktree performance,
     they'd probably make their own worktrees). And it's trickier to get
     right.

  2. Collapse the main and worktree repos into a single scratch repo.
     This can be done by copying everything from both, preferring any
     files from the worktree repo.

This patch does the second one. With this applied, the example above
results in p0000 running successfully.

Reported-by: Derrick Stolee <dstolee@microsoft.com>
Signed-off-by: Jeff King <peff@peff.net>
Reviewed-by: Derrick Stolee <dstolee@microsoft.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2021-02-26 14:21:04 -08:00
Jeff King
fbf20aeeef p5303: measure time to repack with keep
Add two new tests to measure repack performance. Both tests split the
repository into synthetic "pushes", and then leave the remaining objects
in a big base pack.

The first new test marks an empty pack as "kept" and then passes
--honor-pack-keep to avoid including objects in it. That doesn't change
the resulting pack, but it does let us compare to the normal repack case
to see how much overhead we add to check whether objects are kept or
not.

The other test is of --stdin-packs, which gives us a sense of how that
number scales based on the number of packs we provide as input. In each
of those tests, the empty pack isn't considered, but the residual pack
(objects that were left over and not included in one of the synthetic
push packs) is marked as kept.

(Note that in the single-pack case of the --stdin-packs test, there is
nothing do since there are no non-excluded packs).

Here are some timings on a recent clone of the kernel:

  5303.5: repack (1)                          57.26(54.59+10.84)
  5303.6: repack with kept (1)                57.33(54.80+10.51)

in the 50-pack case, things start to slow down:

  5303.11: repack (50)                        71.54(88.57+4.84)
  5303.12: repack with kept (50)              85.12(102.05+4.94)

and by the time we hit 1,000 packs, things are substantially worse, even
though the resulting pack produced is the same:

  5303.17: repack (1000)                      216.87(490.79+14.57)
  5303.18: repack with kept (1000)            665.63(938.87+15.76)

That's because the code paths around handling .keep files are known to
scale badly; they look in every single pack file to find each object.
Our solution to that was to notice that most repos don't have keep
files, and to make that case a fast path. But as soon as you add a
single .keep, that part of pack-objects slows down again (even if we
have fewer objects total to look at).

Likewise, the scaling is pretty extreme on --stdin-packs (but each
subsequent test is also being asked to do more work):

  5303.7: repack with --stdin-packs (1)       0.01(0.01+0.00)
  5303.13: repack with --stdin-packs (50)     3.53(12.07+0.24)
  5303.19: repack with --stdin-packs (1000)   195.83(371.82+8.10)

Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Taylor Blau <me@ttaylorr.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2021-02-22 23:30:52 -08:00
Jeff King
60bb5f2f5d p5303: add missing &&-chains
These are in a helper function, so the usual chain-lint doesn't notice
them. This function is still not perfect, as it has some git invocations
on the left-hand-side of the pipe, but it's primary purpose is timing,
not finding bugs or correctness issues.

Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Taylor Blau <me@ttaylorr.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2021-02-22 23:30:52 -08:00
Jeff Hostetler
4f2009dce2 p7519: add trace logging during perf test
Add optional trace logging to allow us to better compare performance of
various fsmonitor providers and compare results with non-fsmonitor runs.

Currently, this includes Trace2 logging, but may be extended to include
other trace targets, such as GIT_TRACE_FSMONITOR if desired.

Using this logging helped me explain an odd behavior on MacOS where the
kernel was dropping events and causing the hook to Watchman to timeout.

Signed-off-by: Jeff Hostetler <jeffhost@microsoft.com>
Reviewed-by: Taylor Blau <me@ttaylorr.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2021-02-16 17:14:34 -08:00
Jeff Hostetler
a7556c3bde p7519: move watchman cleanup earlier in the test
Shutdown Watchman after the Watchman-based tests and before the block of
"no fsmonitor" tests.

This helps ensure that Watchman cannot affect the test results for the
other.

Signed-off-by: Jeff Hostetler <jeffhost@microsoft.com>
Reviewed-by: Taylor Blau <me@ttaylorr.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2021-02-16 17:14:34 -08:00
Jeff Hostetler
0917763d67 p7519: fix watchman watch-list test on Windows
Only use the final portion of the test trash directory file name
when verifying that Watchman was started.

On Windows and under the SDK, $GIT_WORKTREE is a cygwin-style
path with forward slashes and a "/c/" drive name.  However
`watchman watch-list` reports a proper Windows-style pathname
with drive letters and backslashes.  This causes the grep to
fail.  Since we don't really care about the full pathname (and
we really don't want to bother with normalizaing them), just see
if the test-name portion of the path is found.

Signed-off-by: Jeff Hostetler <jeffhost@microsoft.com>
Reviewed-by: Taylor Blau <me@ttaylorr.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2021-02-16 17:14:34 -08:00
Jeff Hostetler
eb10e637cf p7519: do not rely on "xargs -d" in test
Convert the test to use a more portable method to update the mtime on a
large number of files under version control.

The Mac version of xargs does not support the "-d" option.
Likewise, the "-0" and "--null" options are not portable.

Furthermore, use `test-tool chmtime` rather than `touch` to update the
mtime to ensure that it is actually updated (especially on file systems
with only whole second resolution).

Signed-off-by: Jeff Hostetler <jeffhost@microsoft.com>
Reviewed-by: Taylor Blau <me@ttaylorr.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2021-02-16 17:14:34 -08:00
Junio C Hamano
938ecaa42f Merge branch 'jk/pretty-lazy-load-commit'
Some pretty-format specifiers do not need the data in commit object
(e.g. "%H"), but we were over-eager to load and parse it, which has
been made even lazier.

* jk/pretty-lazy-load-commit:
  pretty: lazy-load commit data when expanding user-format
2021-02-10 14:48:33 -08:00
Junio C Hamano
6a7bf0ddb2 Merge branch 'jk/p5303-sed-portability-fix' into maint
A perf script was made more portable.

* jk/p5303-sed-portability-fix:
  p5303: avoid sed GNU-ism
2021-02-08 14:05:55 -08:00
Junio C Hamano
4cc0e8794d Merge branch 'jk/p5303-sed-portability-fix'
A perf script was made more portable.

* jk/p5303-sed-portability-fix:
  p5303: avoid sed GNU-ism
2021-02-05 16:40:45 -08:00
Junio C Hamano
e93f5c6878 Merge branch 'nk/perf-fsmonitor-cleanup' into maint
Test fix.

* nk/perf-fsmonitor-cleanup:
  p7519: allow running without watchman prereq
2021-02-05 16:31:22 -08:00
Jeff King
f08b6c553d p5303: avoid sed GNU-ism
Using "1~5" isn't portable. Nobody seems to have noticed, since perhaps
people don't tend to run the perf suite on more exotic platforms. Still,
it's better to set a good example.

We can use:

  perl -ne 'print if $. % 5 == 1'

instead. But we can further observe that perl does a good job of the
other parts of this pipeline, and fold the whole thing together.

Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2021-01-29 15:13:54 -08:00
Jeff King
018b9deba5 pretty: lazy-load commit data when expanding user-format
When we expand a user-format, we try to avoid work that isn't necessary
for the output. For instance, we don't bother parsing the commit header
until we know we need the author, subject, etc.

But we do always load the commit object's contents from disk, even if
the format doesn't require it (e.g., just "%H"). Traditionally this
didn't matter much, because we'd have loaded it as part of the traversal
anyway, and we'd typically have those bytes attached to the commit
struct (or these days, cached in a commit-slab).

But when we have a commit-graph, we might easily get to the point of
pretty-printing a commit without ever having looked at the actual object
contents. We should push off that load (and reencoding) until we're
certain that it's needed.

I think the results of p4205 show the advantage pretty clearly (we serve
parent and tree oids out of the commit struct itself, so they benefit as
well):

  # using git.git as the test repo
  Test                          HEAD^             HEAD
  ----------------------------------------------------------------------
  4205.1: log with %H           0.40(0.39+0.01)   0.03(0.02+0.01) -92.5%
  4205.2: log with %h           0.45(0.44+0.01)   0.09(0.09+0.00) -80.0%
  4205.3: log with %T           0.40(0.39+0.00)   0.04(0.04+0.00) -90.0%
  4205.4: log with %t           0.46(0.46+0.00)   0.09(0.08+0.01) -80.4%
  4205.5: log with %P           0.39(0.39+0.00)   0.03(0.03+0.00) -92.3%
  4205.6: log with %p           0.46(0.46+0.00)   0.10(0.09+0.00) -78.3%
  4205.7: log with %h-%h-%h     0.52(0.51+0.01)   0.15(0.14+0.00) -71.2%
  4205.8: log with %an-%ae-%s   0.42(0.41+0.00)   0.42(0.41+0.01) +0.0%

  # using linux.git as the test repo
  Test                          HEAD^             HEAD
  ----------------------------------------------------------------------
  4205.1: log with %H           7.12(6.97+0.14)   0.76(0.65+0.11) -89.3%
  4205.2: log with %h           7.35(7.19+0.16)   1.30(1.19+0.11) -82.3%
  4205.3: log with %T           7.58(7.42+0.15)   1.02(0.94+0.08) -86.5%
  4205.4: log with %t           8.05(7.89+0.15)   1.55(1.41+0.13) -80.7%
  4205.5: log with %P           7.12(7.01+0.10)   0.76(0.69+0.07) -89.3%
  4205.6: log with %p           7.38(7.27+0.10)   1.32(1.20+0.12) -82.1%
  4205.7: log with %h-%h-%h     7.81(7.67+0.13)   1.79(1.67+0.12) -77.1%
  4205.8: log with %an-%ae-%s   7.90(7.74+0.15)   7.81(7.66+0.15) -1.1%

I added the final test to show where we don't improve (the 1% there is
just lucky noise), but also as a regression test to make sure we're not
doing anything stupid like loading the commit multiple times when there
are several placeholders that need it.

Reported-by: Michael Haggerty <mhagger@alum.mit.edu>
Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2021-01-28 14:07:35 -08:00
Junio C Hamano
7bfa022993 Merge branch 'nk/perf-fsmonitor-cleanup'
Test fix.

* nk/perf-fsmonitor-cleanup:
  p7519: allow running without watchman prereq
2021-01-15 15:20:29 -08:00
Junio C Hamano
d3aff11c3e Merge branch 'es/perf-export-fix'
Tweak unneeded recursion from a test framework helper function.

* es/perf-export-fix:
  t/perf: avoid unnecessary test_export() recursion
2021-01-06 23:33:44 -08:00
Taylor Blau
cc2d43be2b p7519: allow running without watchman prereq
p7519 measures the performance of the fsmonitor code. To do this, it
uses the installed copy of Watchman. If Watchman isn't installed, a noop
integration script is installed in its place.

When in the latter mode, it is expected that the script should not write
a "last update token": in fact, it doesn't write anything at all since
the script is blank.

Commit 33226af42b (t/perf/fsmonitor: improve error message if typoing
hook name, 2020-10-26) made sure that running 'git update-index
--fsmonitor' did not write anything to stderr, but this is not the case
when using the empty Watchman script, since Git will complain that:

    $ which watchman
    watchman not found
    $ cat .git/hooks/fsmonitor-empty
    $ git -c core.fsmonitor=.git/hooks/fsmonitor-empty update-index --fsmonitor
    warning: Empty last update token.

Prior to 33226af42b, the output wasn't checked at all, which allowed
this noop mode to work. But, 33226af42b breaks p7519 when running it
without a 'watchman(1)' on your system.

Handle this by only checking that the stderr is empty only when running
with a real watchman executable. Otherwise, assert that the error
message is the expected one when running in the noop mode.

Signed-off-by: Taylor Blau <me@ttaylorr.com>
Acked-by: Nipunn Koorapati <nipunn@dropbox.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2021-01-06 13:48:25 -08:00
Eric Sunshine
5bc12c11cc t/perf: avoid unnecessary test_export() recursion
test_export() has been self-recursive since its inception even though a
simple for-loop would have served just as well to append its arguments
to the `test_export_` variable separated by the pipe character "|".
Recently `test_export_` was changed instead to a space-separated list of
tokens to be exported, an operation which can be accomplished via a
single simple assignment, with no need for looping or recursion.
Therefore, simplify the implementation.

While at it, take advantage of the fact that variable names to be
exported are shell identifiers, thus won't be composed of special
characters or whitespace, thus simple a `$*` can be used rather than
magical `"$@"`.

Signed-off-by: Eric Sunshine <sunshine@sunshineco.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2020-12-22 13:45:36 -08:00
Junio C Hamano
d4187bd4d5 Merge branch 'es/perf-export-fix'
Dev-support fix for BSD.

* es/perf-export-fix:
  t/perf: fix test_export() failure with BSD `sed`
2020-12-18 15:15:18 -08:00
Eric Sunshine
f4698738f9 t/perf: fix test_export() failure with BSD sed
test_perf() runs each test in its own subshell which makes it difficult
to persist variables between tests. test_export() addresses this
shortcoming by grabbing the values of specified variables after a test
runs but before the subshell exits, and writes those values to a file
which is loaded into the environment of subsequent tests.

To grab the values to be persisted, test_export() pipes the output of
the shell's builtin `set` command through `sed` which plucks them out
using a regular expression along the lines of `s/^(var1|var2)/.../p`.
Unfortunately, though, this use of alternation is not portable. For
instance, BSD-lineage `sed` (including macOS `sed`) does not support it
in the default "basic regular expression" mode (BRE). It may be possible
to enable "extended regular expression" mode (ERE) in some cases with
`sed -E`, however, `-E` is neither portable nor part of POSIX.

Fortunately, alternation is unnecessary in this case and can easily be
avoided, so replace it with a series of simple expressions such as
`s/^var1/.../p;s/^var2/.../p`.

While at it, tighten the expressions so they match the variable names
exactly rather than matching prefixes (i.e. use `s/^var1=/.../p`).

If the requirements of test_export() become more complex in the future,
then an alternative would be to replace `sed` with `perl` which supports
alternation on all platforms, however, the simple elimination of
alternation via multiple `sed` expressions suffices for the present.

Reported-by: Sangeeta <sangunb09@gmail.com>
Diagnosed-by: Philippe Blain <levraiphilippeblain@gmail.com>
Signed-off-by: Eric Sunshine <sunshine@sunshineco.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2020-12-16 11:00:29 -08:00
Junio C Hamano
8e2def76f7 Merge branch 'nk/perf-fsmonitor-cleanup'
Test clean-up.

* nk/perf-fsmonitor-cleanup:
  perf/fsmonitor: use test_must_be_empty helper
2020-12-08 15:11:20 -08:00
Junio C Hamano
1bc550effe Merge branch 'ps/update-ref-multi-transaction'
"git update-ref --stdin" learns to take multiple transactions in a
single session.

* ps/update-ref-multi-transaction:
  update-ref: disallow "start" for ongoing transactions
  p1400: use `git-update-ref --stdin` to test multiple transactions
  update-ref: allow creation of multiple transactions
  t1400: avoid touching refs on filesystem
2020-12-08 15:11:17 -08:00
Nipunn Koorapati
36fa907d7a perf/fsmonitor: use test_must_be_empty helper
Simplify test and make error messages more clear here.
Per feedback from Junio in
33226af42b (t/perf/fsmonitor: improve error message if typoing hook
name, 2020-10-26)

Signed-off-by: Nipunn Koorapati <nipunn@dropbox.com>
Acked-by: Derrick Stolee <dstolee@microsoft.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2020-11-30 13:51:43 -08:00
Patrick Steinhardt
21020430a4 p1400: use git-update-ref --stdin to test multiple transactions
In commit 0a0fbbe3ff (refs: remove lookup cache for
reference-transaction hook, 2020-08-25), a new benchmark was added to
p1400 which has the intention to exercise creation of multiple
transactions in a single process. As git-update-ref wasn't yet able to
create multiple transactions with a single run we instead used git-push.
As its non-atomic version creates a transaction per reference update,
this was the best approximation we could make at that point in time.

Now that `git-update-ref --stdin` supports creation of multiple
transactions, let's convert the benchmark to use that instead. It has
less overhead and it's also a lot clearer what the actual intention is.

Signed-off-by: Patrick Steinhardt <ps@pks.im>
Reviewed-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2020-11-16 13:44:01 -08:00
Nipunn Koorapati
1c6833c800 t/perf/fsmonitor: add benchmark for dirty status
This benchmark covers the git status time for a heavily
dirty directory - benchmarking fsmonitor's refresh

When running to compare our perl vs rs-git-fsmonitor - we see that
the perl script incurs significant overhead - further motivation
to provide a faster implementation within git.

7519.7: status (dirty) (fsmonitor=query-watchman) 10.05(7.78+1.56)
7519.20: status (dirty) (fsmonitor=rs-git-fsmonitor) 6.72(4.37+1.64)
7519.33: status (dirty) (fsmonitor=disabled) 5.62(4.24+2.03)

Signed-off-by: Nipunn Koorapati <nipunn@dropbox.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2020-10-26 16:39:34 -07:00
Nipunn Koorapati
a948864ae7 t/perf/fsmonitor: perf comparison of multiple fsmonitor integrations
Allows for simple perf comparison of different integrations. I ran it
to compare our perl script w/ rs-git-fsmonitor and found 20-30ms of
overhead on every command.

Output looks like this (extra newlines added for readability)

Test                                                        this tree
---------------------------------------------------------------------------
7519.4: status (fsmonitor=query-watchman)                   0.42(0.37+0.05)
7519.5: status -uno (fsmonitor=query-watchman)              0.19(0.12+0.07)
7519.6: status -uall (fsmonitor=query-watchman)             1.36(0.73+0.62)
7519.7: diff (fsmonitor=query-watchman)                     0.14(0.09+0.05)
7519.8: diff -- 0_files (fsmonitor=query-watchman)          0.14(0.11+0.03)
7519.9: diff -- 10_files (fsmonitor=query-watchman)         0.14(0.10+0.04)
7519.10: diff -- 100_files (fsmonitor=query-watchman)       0.14(0.09+0.05)
7519.11: diff -- 1000_files (fsmonitor=query-watchman)      0.14(0.08+0.06)
7519.12: diff -- 10000_files (fsmonitor=query-watchman)     0.14(0.09+0.05)
7519.13: add (fsmonitor=query-watchman)                     2.04(1.32+0.66)

7519.16: status (fsmonitor=rs-git-fsmonitor)                0.39(0.32+0.08)
7519.17: status -uno (fsmonitor=rs-git-fsmonitor)           0.17(0.11+0.06)
7519.18: status -uall (fsmonitor=rs-git-fsmonitor)          1.33(0.71+0.61)
7519.19: diff (fsmonitor=rs-git-fsmonitor)                  0.11(0.07+0.04)
7519.20: diff -- 0_files (fsmonitor=rs-git-fsmonitor)       0.11(0.09+0.03)
7519.21: diff -- 10_files (fsmonitor=rs-git-fsmonitor)      0.11(0.09+0.03)
7519.22: diff -- 100_files (fsmonitor=rs-git-fsmonitor)     0.11(0.07+0.04)
7519.23: diff -- 1000_files (fsmonitor=rs-git-fsmonitor)    0.11(0.06+0.06)
7519.24: diff -- 10000_files (fsmonitor=rs-git-fsmonitor)   0.11(0.06+0.06)
7519.25: add (fsmonitor=rs-git-fsmonitor)                   2.03(1.28+0.69)

7519.28: status (fsmonitor=disabled)                        0.77(0.59+0.99)
7519.29: status -uno (fsmonitor=disabled)                   0.42(0.33+0.85)
7519.30: status -uall (fsmonitor=disabled)                  1.59(1.02+1.34)
7519.31: diff (fsmonitor=disabled)                          0.35(0.30+0.81)
7519.32: diff -- 0_files (fsmonitor=disabled)               0.11(0.08+0.04)
7519.33: diff -- 10_files (fsmonitor=disabled)              0.11(0.07+0.04)
7519.34: diff -- 100_files (fsmonitor=disabled)             0.11(0.08+0.03)
7519.35: diff -- 1000_files (fsmonitor=disabled)            0.11(0.10+0.02)
7519.36: diff -- 10000_files (fsmonitor=disabled)           0.12(0.07+0.06)
7519.37: add (fsmonitor=disabled)                           2.24(1.48+1.44)

Signed-off-by: Nipunn Koorapati <nipunn@dropbox.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2020-10-26 16:39:34 -07:00
Nipunn Koorapati
6cba4234a5 t/perf/fsmonitor: initialize test with git reset
Previously, the git add of the previous suiterun would
pollute the numbers in the second run

Before:
Test                                                          this tree
-----------------------------------------------------------------------------
7519.4: status (fsmonitor=fsmonitor-watchman)                 0.40(0.36+0.04)
7519.5: status -uno (fsmonitor=fsmonitor-watchman)            0.19(0.12+0.07)
7519.6: status -uall (fsmonitor=fsmonitor-watchman)           1.36(0.74+0.61)
7519.7: diff (fsmonitor=fsmonitor-watchman)                   0.14(0.10+0.04)
7519.8: diff -- 0_files (fsmonitor=fsmonitor-watchman)        0.14(0.10+0.04)
7519.9: diff -- 10_files (fsmonitor=fsmonitor-watchman)       0.14(0.09+0.05)
7519.10: diff -- 100_files (fsmonitor=fsmonitor-watchman)     0.14(0.10+0.04)
7519.11: diff -- 1000_files (fsmonitor=fsmonitor-watchman)    0.14(0.08+0.06)
7519.12: diff -- 10000_files (fsmonitor=fsmonitor-watchman)   0.14(0.10+0.04)
7519.13: add (fsmonitor=fsmonitor-watchman)                   2.03(1.28+0.69)
7519.16: status (fsmonitor=disabled)                          0.64(0.49+0.90)
7519.17: status -uno (fsmonitor=disabled)                     1.15(0.92+1.00)
7519.18: status -uall (fsmonitor=disabled)                    2.32(1.46+1.55)
7519.19: diff (fsmonitor=disabled)                            1.44(1.12+1.76)
7519.20: diff -- 0_files (fsmonitor=disabled)                 0.11(0.07+0.05)
7519.21: diff -- 10_files (fsmonitor=disabled)                0.11(0.06+0.05)
7519.22: diff -- 100_files (fsmonitor=disabled)               0.11(0.08+0.03)
7519.23: diff -- 1000_files (fsmonitor=disabled)              0.11(0.08+0.04)
7519.24: diff -- 10000_files (fsmonitor=disabled)             0.12(0.06+0.07)
7519.25: add (fsmonitor=disabled)                             2.25(1.47+1.47)

After:
Test                                                          this tree
-----------------------------------------------------------------------------
7519.4: status (fsmonitor=fsmonitor-watchman)                 0.41(0.33+0.09)
7519.5: status -uno (fsmonitor=fsmonitor-watchman)            0.20(0.14+0.07)
7519.6: status -uall (fsmonitor=fsmonitor-watchman)           1.37(0.78+0.58)
7519.7: diff (fsmonitor=fsmonitor-watchman)                   0.14(0.10+0.04)
7519.8: diff -- 0_files (fsmonitor=fsmonitor-watchman)        0.14(0.08+0.06)
7519.9: diff -- 10_files (fsmonitor=fsmonitor-watchman)       0.14(0.09+0.05)
7519.10: diff -- 100_files (fsmonitor=fsmonitor-watchman)     0.14(0.10+0.05)
7519.11: diff -- 1000_files (fsmonitor=fsmonitor-watchman)    0.14(0.11+0.04)
7519.12: diff -- 10000_files (fsmonitor=fsmonitor-watchman)   0.14(0.09+0.05)
7519.13: add (fsmonitor=fsmonitor-watchman)                   2.04(1.27+0.71)
7519.16: status (fsmonitor=disabled)                          0.78(0.59+0.99)
7519.17: status -uno (fsmonitor=disabled)                     0.43(0.32+0.88)
7519.18: status -uall (fsmonitor=disabled)                    1.58(0.96+1.38)
7519.19: diff (fsmonitor=disabled)                            0.36(0.31+0.79)
7519.20: diff -- 0_files (fsmonitor=disabled)                 0.11(0.08+0.03)
7519.21: diff -- 10_files (fsmonitor=disabled)                0.11(0.07+0.04)
7519.22: diff -- 100_files (fsmonitor=disabled)               0.11(0.08+0.04)
7519.23: diff -- 1000_files (fsmonitor=disabled)              0.11(0.07+0.05)
7519.24: diff -- 10000_files (fsmonitor=disabled)             0.12(0.08+0.05)
7519.25: add (fsmonitor=disabled)                             2.25(1.48+1.47)

Signed-off-by: Nipunn Koorapati <nipunn@dropbox.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2020-10-26 16:39:34 -07:00
Nipunn Koorapati
a05b71ab91 t/perf/fsmonitor: factor setup for fsmonitor into function
This prepares for it being called multiple times when
testing different hooks

Signed-off-by: Nipunn Koorapati <nipunn@dropbox.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2020-10-26 16:39:34 -07:00
Nipunn Koorapati
78ff8b3236 t/perf/fsmonitor: silence initial git commit
It is extremely verbose, printing >10K non-useful lines

Signed-off-by: Nipunn Koorapati <nipunn@dropbox.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2020-10-26 16:39:34 -07:00
Nipunn Koorapati
dd79c16746 t/perf/fsmonitor: shorten DESC to basename
The full name is lengthy and makes it hard to read
Before:
7519.3: status (fsmonitor=/home/nipunn/src/server/.git/hooks/rs-git-fsmonitor) 0.02(0.01+0.00)

After
7519.3: status (fsmonitor=rs-git-fsmonitor) 0.03(0.02+0.00)

Signed-off-by: Nipunn Koorapati <nipunn@dropbox.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2020-10-26 16:39:34 -07:00
Nipunn Koorapati
3d53ebcd10 t/perf/fsmonitor: factor description out for readability
There was much duplication here. Prepares for making
changes to the description.

Signed-off-by: Nipunn Koorapati <nipunn@dropbox.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2020-10-26 16:39:34 -07:00
Nipunn Koorapati
33226af42b t/perf/fsmonitor: improve error message if typoing hook name
Previously - it would silently run the perf suite w/o using
fsmonitor - fsmonitor errors are not hard failures.
Now it errors loudly.

GIT_PERF_7519_FSMONITOR="$HOME/rs-git-fsmonitorr"
./p7519-fsmonitor.sh -i -v

fatal: cannot run /home/nipunn/rs-git-fsmonitorr:
No such file or directory
not ok 2 - setup for fsmonitor

Signed-off-by: Nipunn Koorapati <nipunn@dropbox.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2020-10-26 16:39:33 -07:00
Nipunn Koorapati
0288b9322d t/perf/fsmonitor: move watchman setup to one-time-repo-setup
It is only required to be set up once. This prepares for
testing multiple hooks in one invocation.

Signed-off-by: Nipunn Koorapati <nipunn@dropbox.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2020-10-26 16:39:33 -07:00
Nipunn Koorapati
bb7cc7e754 t/perf/fsmonitor: separate one time repo initialization
In preparation for testing multiple fsmonitor hooks

Signed-off-by: Nipunn Koorapati <nipunn@dropbox.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2020-10-26 16:39:33 -07:00
Nipunn Koorapati
2bfa953e5d p7519-fsmonitor: add a git add benchmark
Test                                                                     v2.29.0-rc1       this tree
-----------------------------------------------------------------------------------------------------------------
7519.2: status (fsmonitor=.git/hooks/fsmonitor-watchman)                 1.48(0.79+0.67)   1.48(0.79+0.67) +0.0%
7519.3: status -uno (fsmonitor=.git/hooks/fsmonitor-watchman)            0.16(0.11+0.05)   0.17(0.13+0.04) +6.3%
7519.4: status -uall (fsmonitor=.git/hooks/fsmonitor-watchman)           1.36(0.77+0.58)   1.37(0.72+0.63) +0.7%
7519.5: diff (fsmonitor=.git/hooks/fsmonitor-watchman)                   0.84(0.21+0.63)   0.14(0.11+0.03) -83.3%
7519.6: diff -- 0_files (fsmonitor=.git/hooks/fsmonitor-watchman)        0.12(0.07+0.05)   0.13(0.09+0.04) +8.3%
7519.7: diff -- 10_files (fsmonitor=.git/hooks/fsmonitor-watchman)       0.12(0.09+0.04)   0.13(0.07+0.06) +8.3%
7519.8: diff -- 100_files (fsmonitor=.git/hooks/fsmonitor-watchman)      0.12(0.08+0.05)   0.12(0.08+0.05) +0.0%
7519.9: diff -- 1000_files (fsmonitor=.git/hooks/fsmonitor-watchman)     0.12(0.08+0.05)   0.13(0.09+0.04) +8.3%
7519.10: diff -- 10000_files (fsmonitor=.git/hooks/fsmonitor-watchman)   0.14(0.08+0.06)   0.13(0.07+0.06) -7.1%
7519.11: add (fsmonitor=.git/hooks/fsmonitor-watchman)                   2.75(1.41+1.27)   2.03(1.26+0.70) -26.2%
7519.13: status (fsmonitor=)                                             1.38(1.03+1.04)   1.37(1.04+1.04) -0.7%
7519.14: status -uno (fsmonitor=)                                        1.11(0.83+0.98)   1.10(0.89+0.90) -0.9%
7519.15: status -uall (fsmonitor=)                                       2.30(1.57+1.42)   2.31(1.49+1.50) +0.4%
7519.16: diff (fsmonitor=)                                               1.43(1.13+1.76)   1.46(1.19+1.72) +2.1%
7519.17: diff -- 0_files (fsmonitor=)                                    0.10(0.08+0.04)   0.11(0.08+0.04) +10.0%
7519.18: diff -- 10_files (fsmonitor=)                                   0.10(0.07+0.05)   0.11(0.08+0.04) +10.0%
7519.19: diff -- 100_files (fsmonitor=)                                  0.10(0.07+0.04)   0.11(0.07+0.05) +10.0%
7519.20: diff -- 1000_files (fsmonitor=)                                 0.10(0.08+0.03)   0.11(0.08+0.04) +10.0%
7519.21: diff -- 10000_files (fsmonitor=)                                0.11(0.08+0.05)   0.12(0.07+0.06) +9.1%
7519.22: add (fsmonitor=)                                                2.26(1.46+1.49)   2.27(1.42+1.55) +0.4%

Signed-off-by: Nipunn Koorapati <nipunn@dropbox.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2020-10-20 12:52:23 -07:00
Nipunn Koorapati
471b115745 p7519-fsmonitor: refactor to avoid code duplication
Much of the benchmark code is redundant. This is
easier to understand and edit.

Signed-off-by: Nipunn Koorapati <nipunn@dropbox.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2020-10-20 12:52:23 -07:00
Nipunn Koorapati
ed5a24573d perf lint: add make test-lint to perf tests
Perf tests have not been linted for some time.
They've grown some seq instead of test_seq. This
runs the existing lints on the perf tests as well.

Signed-off-by: Nipunn Koorapati <nipunn@dropbox.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2020-10-20 12:52:23 -07:00
Nipunn Koorapati
89afd5f5ad t/perf: add fsmonitor perf test for git diff
Results for the git-diff fsmonitor optimization
in patch in the parent-rev (using a 400k file repo to test)

As you can see here - git diff with fsmonitor running is
significantly better with this patch series (80% faster on my
workload)!

GIT_PERF_LARGE_REPO=~/src/server ./run v2.29.0-rc1 . -- p7519-fsmonitor.sh

Test                                                                     v2.29.0-rc1       this tree
-----------------------------------------------------------------------------------------------------------------
7519.2: status (fsmonitor=.git/hooks/fsmonitor-watchman)                 1.46(0.82+0.64)   1.47(0.83+0.62) +0.7%
7519.3: status -uno (fsmonitor=.git/hooks/fsmonitor-watchman)            0.16(0.12+0.04)   0.17(0.12+0.05) +6.3%
7519.4: status -uall (fsmonitor=.git/hooks/fsmonitor-watchman)           1.36(0.73+0.62)   1.37(0.76+0.60) +0.7%
7519.5: diff (fsmonitor=.git/hooks/fsmonitor-watchman)                   0.85(0.22+0.63)   0.14(0.10+0.05) -83.5%
7519.6: diff -- 0_files (fsmonitor=.git/hooks/fsmonitor-watchman)        0.12(0.08+0.05)   0.13(0.11+0.02) +8.3%
7519.7: diff -- 10_files (fsmonitor=.git/hooks/fsmonitor-watchman)       0.12(0.08+0.04)   0.13(0.09+0.04) +8.3%
7519.8: diff -- 100_files (fsmonitor=.git/hooks/fsmonitor-watchman)      0.12(0.07+0.05)   0.13(0.07+0.06) +8.3%
7519.9: diff -- 1000_files (fsmonitor=.git/hooks/fsmonitor-watchman)     0.12(0.09+0.04)   0.13(0.08+0.05) +8.3%
7519.10: diff -- 10000_files (fsmonitor=.git/hooks/fsmonitor-watchman)   0.14(0.09+0.05)   0.13(0.10+0.03) -7.1%
7519.12: status (fsmonitor=)                                             1.67(0.93+1.49)   1.67(0.99+1.42) +0.0%
7519.13: status -uno (fsmonitor=)                                        0.37(0.30+0.82)   0.37(0.33+0.79) +0.0%
7519.14: status -uall (fsmonitor=)                                       1.58(0.97+1.35)   1.57(0.86+1.45) -0.6%
7519.15: diff (fsmonitor=)                                               0.34(0.28+0.83)   0.34(0.27+0.83) +0.0%
7519.16: diff -- 0_files (fsmonitor=)                                    0.09(0.06+0.04)   0.09(0.08+0.02) +0.0%
7519.17: diff -- 10_files (fsmonitor=)                                   0.09(0.07+0.03)   0.09(0.06+0.05) +0.0%
7519.18: diff -- 100_files (fsmonitor=)                                  0.09(0.06+0.04)   0.09(0.06+0.04) +0.0%
7519.19: diff -- 1000_files (fsmonitor=)                                 0.09(0.06+0.04)   0.09(0.05+0.05) +0.0%
7519.20: diff -- 10000_files (fsmonitor=)                                0.10(0.08+0.04)   0.10(0.06+0.05) +0.0%

I also added a benchmark for a tiny git diff workload w/ a pathspec.
I see an approximately .02 second overhead added w/ and w/o fsmonitor

From looking at these results, I suspected that refresh_fsmonitor
is already happening during git diff - independent of this patch
series' optimization. Confirmed that suspicion by breaking on
refresh_fsmonitor.

(gdb) bt  [simplified]
0  refresh_fsmonitor  at fsmonitor.c:176
1  ie_match_stat  at read-cache.c:375
2  match_stat_with_submodule at diff-lib.c:237
4  builtin_diff_files  at builtin/diff.c:260
5  cmd_diff  at builtin/diff.c:541
6  run_builtin  at git.c:450
7  handle_builtin  at git.c:700
8  run_argv  at git.c:767
9  cmd_main  at git.c:898
10 main  at common-main.c:52

Signed-off-by: Nipunn Koorapati <nipunn@dropbox.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2020-10-20 12:52:22 -07:00
Nipunn Koorapati
5851462e8d t/perf/p7519-fsmonitor.sh: warm cache on first git status
The first git status would be inflated due to warming of
filesystem cache. This makes the results comparable.

Before
Test                                                             this tree
--------------------------------------------------------------------------------
7519.2: status (fsmonitor=.git/hooks/fsmonitor-watchman)         2.52(1.59+1.56)
7519.3: status -uno (fsmonitor=.git/hooks/fsmonitor-watchman)    0.18(0.12+0.06)
7519.4: status -uall (fsmonitor=.git/hooks/fsmonitor-watchman)   1.36(0.73+0.62)
7519.7: status (fsmonitor=)                                      0.69(0.52+0.90)
7519.8: status -uno (fsmonitor=)                                 0.37(0.28+0.81)
7519.9: status -uall (fsmonitor=)                                1.53(0.93+1.32)

After
Test                                                             this tree
--------------------------------------------------------------------------------
7519.2: status (fsmonitor=.git/hooks/fsmonitor-watchman)         0.39(0.33+0.06)
7519.3: status -uno (fsmonitor=.git/hooks/fsmonitor-watchman)    0.17(0.13+0.05)
7519.4: status -uall (fsmonitor=.git/hooks/fsmonitor-watchman)   1.34(0.77+0.56)
7519.7: status (fsmonitor=)                                      0.70(0.53+0.90)
7519.8: status -uno (fsmonitor=)                                 0.37(0.32+0.78)
7519.9: status -uall (fsmonitor=)                                1.55(1.01+1.25)

Signed-off-by: Nipunn Koorapati <nipunn@dropbox.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2020-10-20 12:52:22 -07:00
Nipunn Koorapati
dc69d47d21 t/perf/README: elaborate on output format
Signed-off-by: Nipunn Koorapati <nipunn@dropbox.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2020-10-20 12:52:22 -07:00
Junio C Hamano
221b755f3a Merge branch 'jk/dont-count-existing-objects-twice'
There is a logic to estimate how many objects are in the
repository, which is mean to run once per process invocation, but
it ran every time the estimated value was requested.

* jk/dont-count-existing-objects-twice:
  packfile: actually set approximate_object_count_valid
2020-09-22 12:36:32 -07:00
Jeff King
67bb65de5d packfile: actually set approximate_object_count_valid
The approximate_object_count() function tries to compute the count only
once per process. But ever since it was introduced in 8e3f52d778
(find_unique_abbrev: move logic out of get_short_sha1(), 2016-10-03), we
failed to actually set the "valid" flag, meaning we'd compute it fresh
on every call.

This turns out not to be _too_ bad, because we're only iterating through
the packed_git list, and not making any system calls. But since it may
get called for every abbreviated hash we output, even this can add up if
you have many packs.

Here are before-and-after timings for a new perf test which just asks
rev-list to abbreviate each commit hash (the test repo is linux.git,
with commit-graphs):

  Test                            origin              HEAD
  ----------------------------------------------------------------------------
  5303.3: rev-list (1)            28.91(28.46+0.44)   29.03(28.65+0.38) +0.4%
  5303.4: abbrev-commit (1)       1.18(1.06+0.11)     1.17(1.02+0.14) -0.8%
  5303.7: rev-list (50)           28.95(28.56+0.38)   29.50(29.17+0.32) +1.9%
  5303.8: abbrev-commit (50)      3.67(3.56+0.10)     3.57(3.42+0.15) -2.7%
  5303.11: rev-list (1000)        30.34(29.89+0.43)   30.82(30.35+0.46) +1.6%
  5303.12: abbrev-commit (1000)   86.82(86.52+0.29)   77.82(77.59+0.22) -10.4%
  5303.15: load 10,000 packs      0.08(0.02+0.05)     0.08(0.02+0.06) +0.0%

It doesn't help at all when we have 1 pack (5303.4), but we get a 10%
speedup when there are 1000 packs (5303.12). That's a modest speedup for
a case that's already slow and we'd hope to avoid in general (note how
slow it is even after, because we have to look in each of those packs
for abbreviations). But it's a one-line change that clearly matches the
original intent, so it seems worth doing.

The included perf test may also be useful for keeping an eye on any
regressions in the overall abbreviation code.

Reported-by: Rasmus Villemoes <rv@rasmusvillemoes.dk>
Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2020-09-17 11:36:14 -07:00
Junio C Hamano
6ddd76fd6c Merge branch 'ps/ref-transaction-hook'
Code simplification by removing ineffective optimization.

* ps/ref-transaction-hook:
  refs: remove lookup cache for reference-transaction hook
2020-08-31 15:49:53 -07:00