unpack-trees: skip stat on fsmonitor-valid files
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. Helped-by: Junio C Hamano <gitster@pobox.com> Helped-by: Kevin Willford <Kevin.Willford@microsoft.com> Signed-off-by: Utsav Shah <utsav@dropbox.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
Utsav Shah committed
Nov 20, 2019 at 08:32 UTC
679f2f9fdd2173d87251aee357dd0e46ce977f42
3 files changed
+29
-9
fsmonitor.c
+17
-6
@@ -191,13 +191,26 @@ void refresh_fsmonitor(struct index_state *istate)
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}
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if (bol < query_result.len)
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fsmonitor_refresh_callback(istate, buf + bol);
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+
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+ /* Now mark the untracked cache for fsmonitor usage */
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+ if (istate->untracked)
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+ istate->untracked->use_fsmonitor = 1;
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} else {
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+
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+ /* We only want to run the post index changed hook if we've actually changed entries, so keep track
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+ * if we actually changed entries or not */
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+ int is_cache_changed = 0;
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/* Mark all entries invalid */
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- for (i = 0; i < istate->cache_nr; i++)
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- istate->cache[i]->ce_flags &= ~CE_FSMONITOR_VALID;
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+ for (i = 0; i < istate->cache_nr; i++) {
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+ if (istate->cache[i]->ce_flags & CE_FSMONITOR_VALID) {
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+ is_cache_changed = 1;
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+ istate->cache[i]->ce_flags &= ~CE_FSMONITOR_VALID;
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+ }
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+ }
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/* If we're going to check every file, ensure we save the results */
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- istate->cache_changed |= FSMONITOR_CHANGED;
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+ if (is_cache_changed)
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+ istate->cache_changed |= FSMONITOR_CHANGED;
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if (istate->untracked)
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istate->untracked->use_fsmonitor = 0;
@@ -259,9 +272,7 @@ void tweak_fsmonitor(struct index_state *istate)
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(uintmax_t)istate->fsmonitor_dirty->bit_size, istate->cache_nr);
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ewah_each_bit(istate->fsmonitor_dirty, fsmonitor_ewah_callback, istate);
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- /* Now mark the untracked cache for fsmonitor usage */
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- if (istate->untracked)
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- istate->untracked->use_fsmonitor = 1;
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+ refresh_fsmonitor(istate);
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}
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ewah_free(istate->fsmonitor_dirty);
t/t7519-status-fsmonitor.sh
+7
-2
@@ -106,6 +106,8 @@ EOF
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# test that "update-index --fsmonitor-valid" sets the fsmonitor valid bit
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test_expect_success 'update-index --fsmonitor-valid" sets the fsmonitor valid bit' '
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+ write_script .git/hooks/fsmonitor-test<<-\EOF &&
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+ EOF
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git update-index --fsmonitor &&
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git update-index --fsmonitor-valid dir1/modified &&
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git update-index --fsmonitor-valid dir2/modified &&
@@ -164,6 +166,8 @@ EOF
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# test that newly added files are marked valid
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test_expect_success 'newly added files are marked valid' '
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+ write_script .git/hooks/fsmonitor-test<<-\EOF &&
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+ EOF
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git add new &&
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git add dir1/new &&
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git add dir2/new &&
@@ -218,11 +222,12 @@ test_expect_success '*only* files returned by the integration script get flagged
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# Ensure commands that call refresh_index() to move the index back in time
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# properly invalidate the fsmonitor cache
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test_expect_success 'refresh_index() invalidates fsmonitor cache' '
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- write_script .git/hooks/fsmonitor-test<<-\EOF &&
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- EOF
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clean_repo &&
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dirty_repo &&
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+ write_integration_script &&
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git add . &&
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+ write_script .git/hooks/fsmonitor-test<<-\EOF &&
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+ EOF
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git commit -m "to reset" &&
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git reset HEAD~1 &&
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git status >actual &&
unpack-trees.c
+5
-1
@@ -1494,6 +1494,9 @@ int unpack_trees(unsigned len, struct tree_desc *t, struct unpack_trees_options
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o->merge_size = len;
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mark_all_ce_unused(o->src_index);
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+ if (o->src_index->fsmonitor_last_update)
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+ o->result.fsmonitor_last_update = o->src_index->fsmonitor_last_update;
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+
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/*
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* Sparse checkout loop #1: set NEW_SKIP_WORKTREE on existing entries
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*/
@@ -2374,7 +2377,8 @@ int oneway_merge(const struct cache_entry * const *src,
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if (old && same(old, a)) {
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int update = 0;
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- if (o->reset && o->update && !ce_uptodate(old) && !ce_skip_worktree(old)) {
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+ if (o->reset && o->update && !ce_uptodate(old) && !ce_skip_worktree(old) &&
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+ !(old->ce_flags & CE_FSMONITOR_VALID)) {
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struct stat st;
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if (lstat(old->name, &st) ||
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ie_match_stat(o->src_index, old, &st, CE_MATCH_IGNORE_VALID|CE_MATCH_IGNORE_SKIP_WORKTREE))