perf: add test for writing the index

A performance test for writing the index to be able to
determine if changes to allocating ondisk structure help.

Signed-off-by: Kevin Willford <kewillf@microsoft.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

diff --git a/Makefile b/Makefile
index 461c845d33cbc5f201096ea4b3e1048492cb0a6a..6e9b80751e274ba622aad269ecd987e32c3a9bad 100644 (file)
--- a/Makefile
+++ b/Makefile
@@ -655,6 +655,7 @@ TEST_PROGRAMS_NEED_X += test-parse-options
 TEST_PROGRAMS_NEED_X += test-path-utils
 TEST_PROGRAMS_NEED_X += test-prio-queue
 TEST_PROGRAMS_NEED_X += test-read-cache
+TEST_PROGRAMS_NEED_X += test-write-cache
 TEST_PROGRAMS_NEED_X += test-ref-store
 TEST_PROGRAMS_NEED_X += test-regex
 TEST_PROGRAMS_NEED_X += test-revision-walking

diff --git a/t/helper/test-write-cache.c b/t/helper/test-write-cache.c
new file mode 100644 (file)
index 0000000..b7ee039
--- /dev/null
+++ b/t/helper/test-write-cache.c
@@ -0,0 +1,23 @@
+#include "cache.h"
+#include "lockfile.h"
+
+static struct lock_file index_lock;
+
+int cmd_main(int argc, const char **argv)
+{
+       int i, cnt = 1, lockfd;
+       if (argc == 2)
+               cnt = strtol(argv[1], NULL, 0);
+       setup_git_directory();
+       read_cache();
+       for (i = 0; i < cnt; i++) {
+               lockfd = hold_locked_index(&index_lock, LOCK_DIE_ON_ERROR);
+               if (0 <= lockfd) {
+                       write_locked_index(&the_index, &index_lock, COMMIT_LOCK);
+               } else {
+                       rollback_lock_file(&index_lock);
+               }
+       }
+
+       return 0;
+}

diff --git a/t/perf/p0007-write-cache.sh b/t/perf/p0007-write-cache.sh
new file mode 100755 (executable)
index 0000000..261fe92
--- /dev/null
+++ b/t/perf/p0007-write-cache.sh
@@ -0,0 +1,29 @@
+#!/bin/sh
+
+test_description="Tests performance of writing the index"
+
+. ./perf-lib.sh
+
+test_perf_default_repo
+
+test_expect_success "setup repo" '
+       if git rev-parse --verify refs/heads/p0006-ballast^{commit}
+       then
+               echo Assuming synthetic repo from many-files.sh
+               git config --local core.sparsecheckout 1
+               cat >.git/info/sparse-checkout <<-EOF
+               /*
+               !ballast/*
+               EOF
+       else
+               echo Assuming non-synthetic repo...
+       fi &&
+       nr_files=$(git ls-files | wc -l)
+'
+
+count=3
+test_perf "write_locked_index $count times ($nr_files files)" "
+       test-write-cache $count
+"
+
+test_done