Add a test utility (test-drop-caches) that enables dropping the file
system cache on Windows.
Add a perf test (p7519-fsmonitor.sh) for fsmonitor.
Signed-off-by: Ben Peart <benpe...@microsoft.com>
Signed-off-by: Ævar Arnfjörð Bjarmason <ava...@gmail.com>
---
Makefile | 1 +
t/helper/test-drop-caches.c | 107 +++++++++++++++++++++++++++++
t/perf/p7519-fsmonitor.sh | 161 ++++++++++++++++++++++++++++++++++++++++++++
3 files changed, 269 insertions(+)
create mode 100644 t/helper/test-drop-caches.c
create mode 100755 t/perf/p7519-fsmonitor.sh
diff --git a/Makefile b/Makefile
index 992dd58801..893947839f 100644
--- a/Makefile
+++ b/Makefile
@@ -648,6 +648,7 @@ TEST_PROGRAMS_NEED_X += test-subprocess
TEST_PROGRAMS_NEED_X += test-svn-fe
TEST_PROGRAMS_NEED_X += test-urlmatch-normalization
TEST_PROGRAMS_NEED_X += test-wildmatch
+TEST_PROGRAMS_NEED_X += test-drop-caches
TEST_PROGRAMS = $(patsubst %,t/helper/%$X,$(TEST_PROGRAMS_NEED_X))
diff --git a/t/helper/test-drop-caches.c b/t/helper/test-drop-caches.c
new file mode 100644
index 0000000000..80830d920b
--- /dev/null
+++ b/t/helper/test-drop-caches.c
@@ -0,0 +1,107 @@
+#include "git-compat-util.h"
+#include <stdio.h>
+
+typedef DWORD NTSTATUS;
+
+#ifdef GIT_WINDOWS_NATIVE
+#include <tchar.h>
+
+#define STATUS_SUCCESS (0x00000000L)
+#define STATUS_PRIVILEGE_NOT_HELD (0xC0000061L)
+
+typedef enum _SYSTEM_INFORMATION_CLASS {
+ SystemMemoryListInformation = 80, // 80, q:
SYSTEM_MEMORY_LIST_INFORMATION; s: SYSTEM_MEMORY_LIST_COMMAND (requires
SeProfileSingleProcessPrivilege)
+} SYSTEM_INFORMATION_CLASS;
+
+// private
+typedef enum _SYSTEM_MEMORY_LIST_COMMAND
+{
+ MemoryCaptureAccessedBits,
+ MemoryCaptureAndResetAccessedBits,
+ MemoryEmptyWorkingSets,
+ MemoryFlushModifiedList,
+ MemoryPurgeStandbyList,
+ MemoryPurgeLowPriorityStandbyList,
+ MemoryCommandMax
+} SYSTEM_MEMORY_LIST_COMMAND;
+
+BOOL GetPrivilege(HANDLE TokenHandle, LPCSTR lpName, int flags)
+{
+ BOOL bResult;
+ DWORD dwBufferLength;
+ LUID luid;
+ TOKEN_PRIVILEGES tpPreviousState;
+ TOKEN_PRIVILEGES tpNewState;
+
+ dwBufferLength = 16;
+ bResult = LookupPrivilegeValueA(0, lpName, &luid);
+ if (bResult)
+ {
+ tpNewState.PrivilegeCount = 1;
+ tpNewState.Privileges[0].Luid = luid;
+ tpNewState.Privileges[0].Attributes = 0;
+ bResult = AdjustTokenPrivileges(TokenHandle, 0, &tpNewState,
(DWORD)((LPBYTE)&(tpNewState.Privileges[1]) - (LPBYTE)&tpNewState),
&tpPreviousState, &dwBufferLength);
+ if (bResult)
+ {
+ tpPreviousState.PrivilegeCount = 1;
+ tpPreviousState.Privileges[0].Luid = luid;
+ tpPreviousState.Privileges[0].Attributes = flags != 0 ?
2 : 0;
+ bResult = AdjustTokenPrivileges(TokenHandle, 0,
&tpPreviousState, dwBufferLength, 0, 0);
+ }
+ }
+ return bResult;
+}
+#endif
+
+int cmd_main(int argc, const char **argv)
+{
+ NTSTATUS status = 1;
+#ifdef GIT_WINDOWS_NATIVE
+ HANDLE hProcess = GetCurrentProcess();
+ HANDLE hToken;
+ if (!OpenProcessToken(hProcess, TOKEN_QUERY | TOKEN_ADJUST_PRIVILEGES,
&hToken))
+ {
+ _ftprintf(stderr, _T("Can't open current process token\n"));
+ return 1;
+ }
+
+ if (!GetPrivilege(hToken, "SeProfileSingleProcessPrivilege", 1))
+ {
+ _ftprintf(stderr, _T("Can't get
SeProfileSingleProcessPrivilege\n"));
+ return 1;
+ }
+
+ CloseHandle(hToken);
+
+ HMODULE ntdll = LoadLibrary(_T("ntdll.dll"));
+ if (!ntdll)
+ {
+ _ftprintf(stderr, _T("Can't load ntdll.dll, wrong Windows
version?\n"));
+ return 1;
+ }
+
+ NTSTATUS(WINAPI *NtSetSystemInformation)(INT, PVOID, ULONG) =
(NTSTATUS(WINAPI *)(INT, PVOID, ULONG))GetProcAddress(ntdll,
"NtSetSystemInformation");
+ if (!NtSetSystemInformation)
+ {
+ _ftprintf(stderr, _T("Can't get function addresses, wrong
Windows version?\n"));
+ return 1;
+ }
+
+ SYSTEM_MEMORY_LIST_COMMAND command = MemoryPurgeStandbyList;
+ status = NtSetSystemInformation(
+ SystemMemoryListInformation,
+ &command,
+ sizeof(SYSTEM_MEMORY_LIST_COMMAND)
+ );
+ if (status == STATUS_PRIVILEGE_NOT_HELD)
+ {
+ _ftprintf(stderr, _T("Insufficient privileges to execute the
memory list command"));
+ }
+ else if (status != STATUS_SUCCESS)
+ {
+ _ftprintf(stderr, _T("Unable to execute the memory list command
%lX"), status);
+ }
+#endif
+
+ return status;
+}
diff --git a/t/perf/p7519-fsmonitor.sh b/t/perf/p7519-fsmonitor.sh
new file mode 100755
index 0000000000..e41905cb9b
--- /dev/null
+++ b/t/perf/p7519-fsmonitor.sh
@@ -0,0 +1,161 @@
+#!/bin/sh
+
+test_description="Test core.fsmonitor"
+
+. ./perf-lib.sh
+
+# This has to be run with GIT_PERF_REPEAT_COUNT=1 to generate valid results.
+# Otherwise the caching that happens for the nth run will negate the validity
+# of the comparisons.
+if [ "$GIT_PERF_REPEAT_COUNT" -ne 1 ]
+then
+ echo "warning: This test must be run with GIT_PERF_REPEAT_COUNT=1 to
generate valid results." >&2
+ echo "warning: Setting GIT_PERF_REPEAT_COUNT=1" >&2
+ GIT_PERF_REPEAT_COUNT=1
+fi
+
+test_perf_large_repo
+test_checkout_worktree
+
+# Convert unix style paths to what Watchman expects
+case "$(uname -s)" in
+MINGW*|MSYS_NT*)
+ GIT_WORK_TREE="$(cygpath -aw "$PWD" | sed 's,\\,/,g')"
+ ;;
+*)
+ GIT_WORK_TREE="$PWD"
+ ;;
+esac
+
+# The big win for using fsmonitor is the elimination of the need to scan
+# the working directory looking for changed files and untracked files. If
+# the file information is all cached in RAM, the benefits are reduced.
+
+flush_disk_cache () {
+ case "$(uname -s)" in
+ MINGW*|MSYS_NT*)
+ sync && test-drop-caches
+ ;;
+ *)
+ sudo sync && echo 3 | sudo tee /proc/sys/vm/drop_caches
+ ;;
+ esac
+
+}
+
+test_lazy_prereq UNTRACKED_CACHE '
+ { git update-index --test-untracked-cache; ret=$?; } &&
+ test $ret -ne 1
+'
+
+test_expect_success "setup" '
+ # Maybe set untrackedCache & splitIndex depending on the environment
+ if test -n "$GIT_PERF_7519_UNTRACKED_CACHE"
+ then
+ git config core.untrackedCache "$GIT_PERF_7519_UNTRACKED_CACHE"
+ else
+ if test_have_prereq UNTRACKED_CACHE
+ then
+ git config core.untrackedCache true
+ else
+ git config core.untrackedCache false
+ fi
+ fi &&
+
+ if test -n "$GIT_PERF_7519_SPLIT_INDEX"
+ then
+ git config core.splitIndex "$GIT_PERF_7519_SPLIT_INDEX"
+ fi &&
+
+ # Hook scaffolding
+ mkdir .git/hooks &&
+ cp ../../../templates/hooks--query-fsmonitor.sample
.git/hooks/query-fsmonitor &&
+
+ # have Watchman monitor the test folder
+ watchman watch "$GIT_WORK_TREE" &&
+ watchman watch-list | grep -q -F "$GIT_WORK_TREE"
+'
+
+# Worst case without fsmonitor
+test_expect_success "clear fs cache" '
+ git config core.fsmonitor false &&
+ flush_disk_cache
+'
+test_perf "status (fsmonitor=false, cold fs cache)" '
+ git status
+'
+
+# Best case without fsmonitor
+test_perf "status (fsmonitor=false, warm fs cache)" '
+ git status
+'
+
+# Let's see if -uno & -uall make any difference
+test_expect_success "clear fs cache" '
+ flush_disk_cache
+'
+test_perf "status -uno (fsmonitor=false, cold fs cache)" '
+ git status -uno
+'
+
+test_expect_success "clear fs cache" '
+ flush_disk_cache
+'
+test_perf "status -uall (fsmonitor=false, cold fs cache)" '
+ git status -uall
+'
+
+# The first run with core.fsmonitor=true has to do a normal scan and write
+# out the index extension.
+test_expect_success "populate extension" '
+ # core.preloadIndex defeats the benefits of core.fsMonitor as it
+ # calls lstat for the index entries. Turn it off as _not_ doing
+ # the work is faster than doing the work across multiple threads.
+ git config core.fsmonitor true &&
+ git config core.preloadIndex false &&
+ git status
+'
+
+# Worst case with fsmonitor
+test_expect_success "shutdown fsmonitor, clear fs cache" '
+ watchman shutdown-server &&
+ flush_disk_cache
+'
+test_perf "status (fsmonitor=true, cold fs cache, cold fsmonitor)" '
+ git status
+'
+
+# Best case with fsmonitor
+test_perf "status (fsmonitor=true, warm fs cache, warm fsmonitor)" '
+ git status
+'
+
+# Best improved with fsmonitor (compare to worst case without fsmonitor)
+test_expect_success "clear fs cache" '
+ flush_disk_cache
+'
+test_perf "status (fsmonitor=true, cold fs cache, warm fsmonitor)" '
+ git status
+'
+
+# Let's see if -uno & -uall make any difference
+test_expect_success "clear fs cache" '
+ flush_disk_cache
+'
+test_perf "status -uno (fsmonitor=true, cold fs cache)" '
+ git status -uno
+'
+
+test_expect_success "clear fs cache" '
+ flush_disk_cache
+'
+test_perf "status -uall (fsmonitor=true, cold fs cache)" '
+ git status -uall
+'
+
+test_expect_success "cleanup" '
+ watchman watch-del "$GIT_WORK_TREE" &&
+ watchman shutdown-server
+'
+
+test_done
--
2.13.0
