[PATCH v2 21/27] t/perf/p7527: add perf test for builtin FSMonitor

["Jeff Hostetler via GitGitGadget" <gitgitgadget@gmail.com>]

From: Jeff Hostetler <jeffhost@microsoft.com>

Signed-off-by: Jeff Hostetler <jeffhost@microsoft.com>
---
 t/perf/p7527-builtin-fsmonitor.sh | 257 ++++++++++++++++++++++++++++++
 1 file changed, 257 insertions(+)
 create mode 100755 t/perf/p7527-builtin-fsmonitor.sh

diff --git a/t/perf/p7527-builtin-fsmonitor.sh b/t/perf/p7527-builtin-fsmonitor.sh
new file mode 100755
index 00000000000..9338b9ea008
--- /dev/null
+++ b/t/perf/p7527-builtin-fsmonitor.sh
@@ -0,0 +1,257 @@
+#!/bin/sh
+
+test_description="Perf test for the builtin FSMonitor"
+
+. ./perf-lib.sh
+
+if ! test_have_prereq FSMONITOR_DAEMON
+then
+	skip_all="fsmonitor--daemon is not supported on this platform"
+	test_done
+fi
+
+test_lazy_prereq UNTRACKED_CACHE '
+	{ git update-index --test-untracked-cache; ret=$?; } &&
+	test $ret -ne 1
+'
+
+# Lie to perf-lib and ask for a new empty repo and avoid
+# the complaints about GIT_PERF_REPO not being big enough
+# the perf hit when GIT_PERF_LARGE_REPO is copied into
+# the trash directory.
+#
+# NEEDSWORK: It would be nice if perf-lib had an option to
+# "borrow" an existing large repo (especially for gigantic
+# monorepos) and use it in-place.  For now, fake it here.
+#
+test_perf_fresh_repo
+
+
+# Use a generated synthetic monorepo.  If it doesn't exist, we will
+# generate it.  If it does exist, we will put it in a known state
+# before we start our timings.
+#
+PARAM_D=5
+PARAM_W=10
+PARAM_F=9
+
+PARAMS="$PARAM_D"."$PARAM_W"."$PARAM_F"
+
+BALLAST_BR=p0006-ballast
+export BALLAST_BR
+
+TMP_BR=tmp_br
+export TMP_BR
+
+REPO=../repos/gen-many-files-"$PARAMS".git
+export REPO
+
+if ! test -d $REPO
+then
+	(cd ../repos; ./many-files.sh -d $PARAM_D -w $PARAM_W -f $PARAM_F)
+fi
+
+
+enable_uc () {
+	git -C $REPO config core.untrackedcache true
+	git -C $REPO update-index --untracked-cache
+	git -C $REPO status >/dev/null 2>&1
+}
+
+disable_uc () {
+	git -C $REPO config core.untrackedcache false
+	git -C $REPO update-index --no-untracked-cache
+	git -C $REPO status >/dev/null 2>&1
+}
+
+start_fsm () {
+	git -C $REPO fsmonitor--daemon start
+	git -C $REPO fsmonitor--daemon status
+	git -C $REPO config core.fsmonitor true
+	git -C $REPO update-index --fsmonitor
+	git -C $REPO status >/dev/null 2>&1
+}
+
+stop_fsm () {
+	git -C $REPO config --unset core.fsmonitor
+	git -C $REPO update-index --no-fsmonitor
+	test_might_fail git -C $REPO fsmonitor--daemon stop 2>/dev/null
+	git -C $REPO status >/dev/null 2>&1
+}
+
+
+# Ensure that FSMonitor is turned off on the borrowed repo.
+#
+test_expect_success "Setup borrowed repo (fsm+uc)" "
+	stop_fsm &&
+	disable_uc
+"
+
+# Also ensure that it starts in a known state.
+#
+# Because we assume that $GIT_PERF_REPEAT_COUNT > 1, we are not going to time
+# the ballast checkout, since only the first invocation does any work and the
+# subsequent ones just print "already on branch" and quit, so the reported
+# time is not useful.
+#
+# Create a temp branch and do all work relative to it so that we don't
+# accidentially alter the real ballast branch.
+#
+test_expect_success "Setup borrowed repo (temp ballast branch)" "
+	test_might_fail git -C $REPO checkout $BALLAST_BR &&
+	test_might_fail git -C $REPO reset --hard &&
+	git -C $REPO clean -d -f &&
+	test_might_fail git -C $REPO branch -D $TMP_BR &&
+	git -C $REPO branch $TMP_BR $BALLAST_BR &&
+	git -C $REPO checkout $TMP_BR
+"
+
+
+echo Data >data.txt
+
+# NEEDSWORK: We assume that $GIT_PERF_REPEAT_COUNT > 1.  With
+# FSMonitor enabled, we can get a skewed view of status times, since
+# the index MAY (or may not) be updated after the first invocation
+# which will update the FSMonitor Token, so the subsequent invocations
+# may get a smaller response from the daemon.
+#
+do_status () {
+	msg=$1
+
+	test_perf "$msg" "
+		git -C $REPO status >/dev/null 2>&1
+	"
+}
+
+do_matrix () {
+	uc=$1
+	fsm=$2
+
+	t="[uc $uc][fsm $fsm]"
+	MATRIX_BR="$TMP_BR-$uc-$fsm"
+
+	test_expect_success "$t Setup matrix branch" "
+		git -C $REPO clean -d -f &&
+		git -C $REPO checkout $TMP_BR &&
+		test_might_fail git -C $REPO branch -D $MATRIX_BR &&
+		git -C $REPO branch $MATRIX_BR $TMP_BR &&
+		git -C $REPO checkout $MATRIX_BR
+	"
+
+	if test $uc = true
+	then
+		enable_uc
+	else
+		disable_uc
+	fi
+
+	if test $fsm = true
+	then
+		start_fsm
+	else
+		stop_fsm
+	fi
+
+	do_status "$t status after checkout"
+
+	# Modify many files in the matrix branch.
+	# Stage them.
+	# Commit them.
+	# Rollback.
+	#
+	test_expect_success "$t modify tracked files" "
+		find $REPO -name file1 -exec cp data.txt {} \\;
+	"
+
+	do_status "$t status after big change"
+
+	# Don't bother timing the "add" because _REPEAT_COUNT
+	# issue described above.
+	#
+	test_expect_success "$t add all" "
+		git -C $REPO add -A
+	"
+
+	do_status "$t status after add all"
+
+	test_expect_success "$t add dot" "
+		git -C $REPO add .
+	"
+
+	do_status "$t status after add dot"
+
+	test_expect_success "$t commit staged" "
+		git -C $REPO commit -a -m data
+	"
+
+	do_status "$t status after commit"
+
+	test_expect_success "$t reset HEAD~1 hard" "
+		git -C $REPO reset --hard HEAD~1 >/dev/null 2>&1
+	"
+
+	do_status "$t status after reset hard"
+
+	# Create some untracked files.
+	#
+	test_expect_success "$t create untracked files" "
+		cp -R $REPO/ballast/dir1 $REPO/ballast/xxx1
+	"
+
+	do_status "$t status after create untracked files"
+
+	# Remove the new untracked files.
+	#
+	test_expect_success "$t clean -df" "
+		git -C $REPO clean -d -f
+	"
+
+	do_status "$t status after clean"
+
+	if test $fsm = true
+	then
+		stop_fsm
+	fi
+}
+
+# Begin testing each case in the matrix that we care about.
+#
+uc_values="false"
+test_have_prereq UNTRACKED_CACHE && uc_values="false true"
+
+fsm_values="false true"
+
+for uc_val in $uc_values
+do
+	for fsm_val in $fsm_values
+	do
+		do_matrix $uc_val $fsm_val
+	done
+done
+
+cleanup () {
+	uc=$1
+	fsm=$2
+
+	MATRIX_BR="$TMP_BR-$uc-$fsm"
+
+	test_might_fail git -C $REPO branch -D $MATRIX_BR
+}
+
+
+# We're borrowing this repo.  We should leave it in a clean state.
+#
+test_expect_success "Cleanup temp and matrix branches" "
+	git -C $REPO clean -d -f &&
+	test_might_fail git -C $REPO checkout $BALLAST_BR &&
+	test_might_fail git -C $REPO branch -D $TMP_BR &&
+	for uc_val in $uc_values
+	do
+		for fsm_val in $fsm_values
+		do
+			cleanup $uc_val $fsm_val
+		done
+	done
+"
+
+test_done
-- 
gitgitgadget