From: Utsav Shah <utsav@xxxxxxxxxxx>
The index might be aware that a file hasn't modified via fsmonitor, but
unpack-trees did not pay attention to it and checked via ie_match_stat
which can be inefficient on certain filesystems. This significantly slows
down commands that run oneway_merge, like checkout and reset --hard.
This patch makes oneway_merge check whether a file is considered
unchanged through fsmonitor and skips ie_match_stat on it. unpack-trees
also now correctly copies over fsmonitor validity state from the source
index. Finally, for correctness, we force a refresh of fsmonitor state in
tweak_fsmonitor.
After this change, commands like stash (that use reset --hard
internally) go from 8s or more to ~2s on a 250k file repository on a
mac.
Changes since the last version are:
* The sanity checks around accessing the fsmonitor_dirty bitmap have
been moved to another patch, which is in message id [1]
* Unintended indentation changes in fsmonitor have been removed
* A comment explaining what untracked->use_fsmonitor means has been
re-added (it was dropped in the previous version)
* A few "helped-by" entries have been added to the patch
[1]: (xmqqzhh0d0ma.fsf@xxxxxxxxxxxxxxxxxxxxxxxxx)
Helped-by: Junio C Hamano <gitster@xxxxxxxxx>
Helped-by: Kevin Willford <Kevin.Willford@xxxxxxxxxxxxx>
Signed-off-by: Utsav Shah <utsav@xxxxxxxxxxx>
---
fsmonitor.c | 23 +++++++++++++++++------
t/t7519-status-fsmonitor.sh | 9 +++++++--
unpack-trees.c | 6 +++++-
3 files changed, 29 insertions(+), 9 deletions(-)
diff --git a/fsmonitor.c b/fsmonitor.c
index 1f4aa1b150..0d270da80f 100644
--- a/fsmonitor.c
+++ b/fsmonitor.c
@@ -189,13 +189,26 @@ void refresh_fsmonitor(struct index_state *istate)
}
if (bol < query_result.len)
fsmonitor_refresh_callback(istate, buf + bol);
+
+ /* Now mark the untracked cache for fsmonitor usage */
+ if (istate->untracked)
+ istate->untracked->use_fsmonitor = 1;
} else {
+
+ /* We only want to run the post index changed hook if we've actually changed entries, so keep track
+ * if we actually changed entries or not */
+ int is_cache_changed = 0;
/* Mark all entries invalid */
- for (i = 0; i < istate->cache_nr; i++)
- istate->cache[i]->ce_flags &= ~CE_FSMONITOR_VALID;
+ for (i = 0; i < istate->cache_nr; i++) {
+ if (istate->cache[i]->ce_flags & CE_FSMONITOR_VALID) {
+ is_cache_changed = 1;
+ istate->cache[i]->ce_flags &= ~CE_FSMONITOR_VALID;
+ }
+ }
/* If we're going to check every file, ensure we save the results */
- istate->cache_changed |= FSMONITOR_CHANGED;
+ if (is_cache_changed)
+ istate->cache_changed |= FSMONITOR_CHANGED;
if (istate->untracked)
istate->untracked->use_fsmonitor = 0;
@@ -257,9 +270,7 @@ void tweak_fsmonitor(struct index_state *istate)
(uintmax_t)istate->fsmonitor_dirty->bit_size, istate->cache_nr);
ewah_each_bit(istate->fsmonitor_dirty, fsmonitor_ewah_callback, istate);
- /* Now mark the untracked cache for fsmonitor usage */
- if (istate->untracked)
- istate->untracked->use_fsmonitor = 1;
+ refresh_fsmonitor(istate);
}
ewah_free(istate->fsmonitor_dirty);
diff --git a/t/t7519-status-fsmonitor.sh b/t/t7519-status-fsmonitor.sh
index d8df990972..69908b6a9b 100755
--- a/t/t7519-status-fsmonitor.sh
+++ b/t/t7519-status-fsmonitor.sh
@@ -106,6 +106,8 @@ EOF
# test that "update-index --fsmonitor-valid" sets the fsmonitor valid bit
test_expect_success 'update-index --fsmonitor-valid" sets the fsmonitor valid bit' '
+ write_script .git/hooks/fsmonitor-test<<-\EOF &&
+ EOF
git update-index --fsmonitor &&
git update-index --fsmonitor-valid dir1/modified &&
git update-index --fsmonitor-valid dir2/modified &&
@@ -164,6 +166,8 @@ EOF
# test that newly added files are marked valid
test_expect_success 'newly added files are marked valid' '
+ write_script .git/hooks/fsmonitor-test<<-\EOF &&
+ EOF
git add new &&
git add dir1/new &&
git add dir2/new &&
@@ -218,11 +222,12 @@ test_expect_success '*only* files returned by the integration script get flagged
# Ensure commands that call refresh_index() to move the index back in time
# properly invalidate the fsmonitor cache
test_expect_success 'refresh_index() invalidates fsmonitor cache' '
- write_script .git/hooks/fsmonitor-test<<-\EOF &&
- EOF
clean_repo &&
dirty_repo &&
+ write_integration_script &&
git add . &&
+ write_script .git/hooks/fsmonitor-test<<-\EOF &&
+ EOF
git commit -m "to reset" &&
git reset HEAD~1 &&
git status >actual &&
diff --git a/unpack-trees.c b/unpack-trees.c
index 33ea7810d8..fc5ceb932c 100644
--- a/unpack-trees.c
+++ b/unpack-trees.c
@@ -1504,6 +1504,9 @@ int unpack_trees(unsigned len, struct tree_desc *t, struct unpack_trees_options
o->merge_size = len;
mark_all_ce_unused(o->src_index);
+ if (o->src_index->fsmonitor_last_update)
+ o->result.fsmonitor_last_update = o->src_index->fsmonitor_last_update;
+
/*
* Sparse checkout loop #1: set NEW_SKIP_WORKTREE on existing entries
*/
@@ -2384,7 +2387,8 @@ int oneway_merge(const struct cache_entry * const *src,
if (old && same(old, a)) {
int update = 0;
- if (o->reset && o->update && !ce_uptodate(old) && !ce_skip_worktree(old)) {
+ if (o->reset && o->update && !ce_uptodate(old) && !ce_skip_worktree(old) &&
+ !(old->ce_flags & CE_FSMONITOR_VALID)) {
struct stat st;
if (lstat(old->name, &st) ||
ie_match_stat(o->src_index, old, &st, CE_MATCH_IGNORE_VALID|CE_MATCH_IGNORE_SKIP_WORKTREE))
--
gitgitgadget
