From ff15d509b89edd4830d85d53cea3079a6b0c1c08 Mon Sep 17 00:00:00 2001
From: Derrick Stolee <dstolee@microsoft.com>
Date: Mon, 11 Jan 2021 08:53:09 -0500
Subject: [PATCH 8/9] test-lib: test_region looks for trace2 regions
Most test cases can verify Git's behavior using input/output
expectations or changes to the .git directory. However, sometimes we
want to check that Git did or did not run a certain section of code.
This is particularly important for performance-only features that we
want to ensure have been enabled in certain cases.
Add a new 'test_region' function that checks if a trace2 region was
entered and left in a given trace2 event log.
There is one existing test (t0500-progress-display.sh) that performs
this check already, so use the helper function instead. Note that this
changes the expectations slightly. The old test (incorrectly) used two
patterns for the 'grep' invocation, but this performs an OR of the
patterns, not an AND. This means that as long as one region_enter event
was logged, the test would succeed, even if it was not due to the
progress category.
More uses will be added in a later change.
t6423-merge-rename-directories.sh also greps for region_enter lines, but
it verifies the number of such lines, which is not the same as an
existence check.
Signed-off-by: Derrick Stolee <dstolee@microsoft.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
A future feature will want to load the sparse-checkout patterns into a
pattern_list, but the current mechanism to do so is a bit complicated.
This is made difficult due to needing to find the sparse-checkout file
in different ways throughout the codebase.
The logic implemented in the new get_sparse_checkout_patterns() was
duplicated in populate_from_existing_patterns() in unpack-trees.c. Use
the new method instead, keeping the logic around handling the struct
unpack_trees_options.
The callers to get_sparse_checkout_filename() in
builtin/sparse-checkout.c manipulate the sparse-checkout file directly,
so it is not appropriate to replace logic in that file with
get_sparse_checkout_patterns().
Signed-off-by: Derrick Stolee <dstolee@microsoft.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
The lazy_init_name_hash() populates a hashset with all filenames and
another with all directories represented in the index. This is run only
if we need to use the hashsets to check for existence or case-folding
renames.
Place trace2 regions where there is already a performance trace.
Signed-off-by: Derrick Stolee <dstolee@microsoft.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
It will be helpful to add behavior to index operations that might
trigger an object lookup. Since each index belongs to a specific
repository, add a 'repo' pointer to struct index_state that allows
access to this repository.
Add a BUG() statement if the repo already has an index, and the index
already has a repo, but somehow the index points to a different repo.
This will prevent future changes from needing to pass an additional
'struct repository *repo' parameter and instead rely only on the 'struct
index_state *istate' parameter.
Signed-off-by: Derrick Stolee <dstolee@microsoft.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
The index has an fsmonitor_dirty bitmap that records which index entries
are "dirty" based on the response from the FSMonitor. If this bitmap
ever grows larger than the index, then there was an error in how it was
constructed, and it was probably a developer's bug.
There are several BUG() statements that are very similar, so replace
these uses with a simpler assert_index_minimum(). Since there is one
caller that uses a custom 'pos' value instead of the bit_size member, we
cannot simplify it too much. However, the error string is identical in
each, so this simplifies things.
Be sure to add one when checking if a position if valid, since the
minimum is a bound on the expected size.
The end result is that the code is simpler to read while also preserving
these assertions for developers in the FSMonitor space.
Signed-off-by: Derrick Stolee <dstolee@microsoft.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
This method will be helpful to use outside of cache-tree.c in a later
feature. The implementation is subtle due to subtree_name_cmp() sorting
by length and then lexicographically.
Signed-off-by: Derrick Stolee <dstolee@microsoft.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
The verify_cache() method takes an array of cache entries and a count,
but these are always provided directly from a struct index_state. Use
a pointer to the full structure instead.
There is a subtle point when istate->cache_nr is zero that subtracting
one will underflow. This triggers a failure in t0000-basic.sh, among
others. Use "i + 1 < istate->cache_nr" to avoid these strange
comparisons. Convert i to be unsigned as well, which also removes the
potential signed overflow in the unlikely case that cache_nr is over 2.1
billion entries. The 'funny' variable has a maximum value of 11, so
making it unsigned does not change anything of importance.
Signed-off-by: Derrick Stolee <dstolee@microsoft.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Make the method safer by allocating a cache_tree member for the given
index_state if it is not already present. This is preferrable to a
BUG() statement or returning with an error because future callers will
want to populate an empty cache-tree using this method.
Callers can also remove their conditional allocations of cache_tree.
Also drop local variables that can be found directly from the 'istate'
parameter.
Signed-off-by: Derrick Stolee <dstolee@microsoft.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
The previous change reduced time spent in strlen() while comparing
consecutive paths in verify_cache(), but we can do better. The
conditional checks the existence of a directory separator at the correct
location, but only after doing a string comparison. Swap the order to be
logically equivalent but perform fewer string comparisons.
To test the effect on performance, I used a repository with over three
million paths in the index. I then ran the following command on repeat:
git -c index.threads=1 commit --amend --allow-empty --no-edit
Here are the measurements over 10 runs after a 5-run warmup:
Benchmark #1: v2.30.0
Time (mean ± σ): 854.5 ms ± 18.2 ms
Range (min … max): 825.0 ms … 892.8 ms
Benchmark #2: Previous change
Time (mean ± σ): 833.2 ms ± 10.3 ms
Range (min … max): 815.8 ms … 849.7 ms
Benchmark #3: This change
Time (mean ± σ): 815.5 ms ± 18.1 ms
Range (min … max): 795.4 ms … 849.5 ms
This change is 2% faster than the previous change and 5% faster than
v2.30.0.
Signed-off-by: Derrick Stolee <dstolee@microsoft.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Use the name length field of cache entries instead of calculating its
value anew.
Signed-off-by: René Scharfe <l.s.r@web.de>
Signed-off-by: Derrick Stolee <dstolee@microsoft.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
The end of the cache tree index extension format trails off with
ellipses ever since 23fcc98 (doc: technical details about the index
file format, 2011-03-01). While an intuitive reader could gather what
this means, it could be better to use "and so on" instead.
Really, this is only justified because I also wanted to point out that
the number of subtrees in the index format is used to determine when the
recursive depth-first-search stack should be "popped." This should help
to add clarity to the format.
Signed-off-by: Derrick Stolee <dstolee@microsoft.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
I had difficulty in my efforts to learn about the cache tree extension
based on the documentation and code because I had an incorrect
assumption about how it behaved. This might be due to some ambiguity in
the documentation, so this change modifies the beginning of the cache
tree format by expanding the description of the feature.
My hope is that this documentation clarifies a few things:
1. There is an in-memory recursive tree structure that is constructed
from the extension data. This structure has a few differences, such
as where the name is stored.
2. What does it mean for an entry to be invalid?
3. When exactly are "new" trees created?
Helped-by: Junio C Hamano <gitster@pobox.com>
Signed-off-by: Derrick Stolee <dstolee@microsoft.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
The index has a "cache tree" extension. This corresponds to a
significant API implemented in cache-tree.[ch]. However, there are a few
places that refer to this erroneously as "cached tree". These are rare,
but notably the index-format.txt file itself makes this error.
The only other reference is in t7104-reset-hard.sh.
Reported-by: Junio C Hamano <gitster@pobox.com>
Signed-off-by: Derrick Stolee <dstolee@microsoft.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Commands such as "git reset --hard" rebuild the in-memory representation
of the cache tree index extension by parsing tree objects starting at a
known root tree. The performance of this operation can vary widely
depending on the width and depth of the repository's working directory
structure. Measure the time in this operation using trace2 regions in
prime_cache_tree().
Signed-off-by: Derrick Stolee <dstolee@microsoft.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
As we write or read the cache tree index extension, it can be good to
isolate how much of the file I/O time is spent constructing this
in-memory tree from the existing index or writing it out again to the
new index file. Use trace2 regions to indicate that we are spending time
on this operation.
Signed-off-by: Derrick Stolee <dstolee@microsoft.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
This matches a trace_performance_enter()/trace_performance_leave() pair
added by 0d1ed59 (unpack-trees: add performance tracing, 2018-08-18).
Signed-off-by: Derrick Stolee <dstolee@microsoft.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
The unpack_trees() method is quite complicated and its performance can
change dramatically depending on how it is used. We already have some
performance tracing regions, but they have not been updated to the
trace2 API. Do so now.
We already have trace2 regions in unpack_trees.c:clear_ce_flags(), which
uses a linear scan through the index without recursing into trees.
Signed-off-by: Derrick Stolee <dstolee@microsoft.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
The traverse_trees() method recursively walks through trees, but also
prunes the tree-walk based on a callback. Some callers, such as
unpack_trees(), are quite complicated and can have wildly different
performance between two different commands.
Create constants that count these values and then report the results at
the end of a process. These counts are cumulative across multiple "root"
instances of traverse_trees(), but they provide reproducible values for
demonstrating improvements to the pruning algorithm when possible.
This change is modeled after a similar statistics reporting in 42e50e78
(revision.c: add trace2 stats around Bloom filter usage, 2020-04-06).
Signed-off-by: Derrick Stolee <dstolee@microsoft.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Hotfix for a topic of this cycle.
* ma/maintenance-crontab-fix:
t7900-maintenance: test for magic markers
gc: fix handling of crontab magic markers
git-maintenance.txt: add missing word
Test coverage fix.
* js/no-more-prepare-for-main-in-test:
tests: drop the `PREPARE_FOR_MAIN_BRANCH` prereq
t9902: use `main` as initial branch name
t6302: use `main` as initial branch name
t5703: use `main` as initial branch name
t5510: use `main` as initial branch name
t5505: finalize transitioning to using the branch name `main`
t3205: finalize transitioning to using the branch name `main`
t3203: complete the transition to using the branch name `main`
t3201: finalize transitioning to using the branch name `main`
t3200: finish transitioning to the initial branch name `main`
t1400: use `main` as initial branch name
"git pack-redandant" when there is only one packfile used to crash,
which has been corrected.
* jx/pack-redundant-on-single-pack:
pack-redundant: fix crash when one packfile in repo
The 'linkgit' Asciidoc macro is misspelled as 'linkit' in the
description of 'GIT_SEQUENCE_EDITOR' since the addition of that variable
to git(1) in 902a126eca (doc: mention GIT_SEQUENCE_EDITOR and
'sequence.editor' more, 2020-08-31). Also, it uses two colons instead of
one.
Fix that.
Signed-off-by: Philippe Blain <levraiphilippeblain@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Comment did not adequately explain how the two loops work
together to achieve the goal of querying for matching of any
negative refspec.
Signed-off-by: Nipunn Koorapati <nipunn@dropbox.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
The logic added to check for negative pathspec match by c0192df630
(refspec: add support for negative refspecs, 2020-09-30) looks at
refspec->src assuming it is never NULL, however when
remote.origin.push is set to ":", then refspec->src is NULL,
causing a segfault within strcmp.
Tell git to handle matching refspec by adding the needle to the
set of positively matched refspecs, since matching ":" refspecs
match anything as src.
Add test for matching refspec pushes fetch-negative-refspec
both individually and in combination with a negative refspec.
Signed-off-by: Nipunn Koorapati <nipunn@dropbox.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
When we insert our "BEGIN" and "END" markers into the cron table, it's
so that a Git version from many years into the future would be able to
identify this region in the cron table. Let's add a test to make sure
that these markers don't ever change.
Signed-off-by: Martin Ågren <martin.agren@gmail.com>
Acked-by: Derrick Stolee <dstolee@microsoft.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
On `git maintenance start`, we add a few entries to the user's cron
table. We wrap our entries using two magic markers, "# BEGIN GIT
MAINTENANCE SCHEDULE" and "# END GIT MAINTENANCE SCHEDULE". At a later
`git maintenance stop`, we will go through the table and remove these
lines. Or rather, we will remove the "BEGIN" marker, the "END" marker
and everything between them.
Alas, we have a bug in how we detect the "END" marker: we don't. As we
loop through all the lines of the crontab, if we are in the "old
region", i.e., the region we're aiming to remove, we make an early
`continue` and don't get as far as checking for the "END" marker. Thus,
once we've seen our "BEGIN", we remove everything until the end of the
file.
Rewrite the logic for identifying these markers. There are four cases
that are mutually exclusive: The current line starts a region or it ends
it, or it's firmly within the region, or it's outside of it (and should
be printed).
Signed-off-by: Martin Ågren <martin.agren@gmail.com>
Acked-by: Derrick Stolee <dstolee@microsoft.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Add a missing "a" before "bunch".
Signed-off-by: Martin Ågren <martin.agren@gmail.com>
Acked-by: Derrick Stolee <dstolee@microsoft.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
This fixes a segmentation fault.
The bug is caused by dereferencing `new_branch_info->commit` when it is
`NULL`, which is the case when the tree-ish argument is actually a tree,
not a commit-ish. This was introduced in 5602b500c3 (builtin/checkout:
fix `git checkout -p HEAD...` bug, 2020-10-07), where we tried to ensure
that the special tree-ish `HEAD...` is handled correctly.
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
* github/master: (42 commits)
Git 2.30-rc1
git-gui: use gray background for inactive text widgets
Another batch before 2.30-rc1
git-gui: Fix selected text colors
Makefile: conditionally include GIT-VERSION-FILE
git-gui: fix colored label backgrounds when using themed widgets
config.mak.uname: remove old NonStop compatibility settings
diff: correct interaction between --exit-code and -I<pattern>
t/perf: fix test_export() failure with BSD `sed`
style: do not "break" in switch() after "return"
compat-util: pretend that stub setitimer() always succeeds
strmap: make callers of strmap_remove() to call it in void context
doc: mention Python 3.x supports
index-format.txt: document v2 format of file system monitor extension
docs: multi-pack-index: remove note about future 'verify' work
init: provide useful advice about init.defaultBranch
get_default_branch_name(): prepare for showing some advice
branch -m: allow renaming a yet-unborn branch
init: document `init.defaultBranch` better
t7900: use --fixed-value in git-maintenance tests
...
