From abf38abec201cded6094801766d69e11a6c112b6 Mon Sep 17 00:00:00 2001 From: Neeraj Singh Date: Thu, 10 Mar 2022 22:43:20 +0000 Subject: core.fsyncmethod: add writeout-only mode This commit introduces the `core.fsyncMethod` configuration knob, which can currently be set to `fsync` or `writeout-only`. The new writeout-only mode attempts to tell the operating system to flush its in-memory page cache to the storage hardware without issuing a CACHE_FLUSH command to the storage controller. Writeout-only fsync is significantly faster than a vanilla fsync on common hardware, since data is written to a disk-side cache rather than all the way to a durable medium. Later changes in this patch series will take advantage of this primitive to implement batching of hardware flushes. When git_fsync is called with FSYNC_WRITEOUT_ONLY, it may fail and the caller is expected to do an ordinary fsync as needed. On Apple platforms, the fsync system call does not issue a CACHE_FLUSH directive to the storage controller. This change updates fsync to do fcntl(F_FULLFSYNC) to make fsync actually durable. We maintain parity with existing behavior on Apple platforms by setting the default value of the new core.fsyncMethod option. Signed-off-by: Neeraj Singh Signed-off-by: Junio C Hamano --- contrib/buildsystems/CMakeLists.txt | 16 ++++++++++++---- 1 file changed, 12 insertions(+), 4 deletions(-) (limited to 'contrib/buildsystems/CMakeLists.txt') diff --git a/contrib/buildsystems/CMakeLists.txt b/contrib/buildsystems/CMakeLists.txt index e44232f85d..3a9e624166 100644 --- a/contrib/buildsystems/CMakeLists.txt +++ b/contrib/buildsystems/CMakeLists.txt @@ -261,10 +261,18 @@ if(CMAKE_SYSTEM_NAME STREQUAL "Windows") NOGDI OBJECT_CREATION_MODE=1 __USE_MINGW_ANSI_STDIO=0 USE_NED_ALLOCATOR OVERRIDE_STRDUP MMAP_PREVENTS_DELETE USE_WIN32_MMAP UNICODE _UNICODE HAVE_WPGMPTR ENSURE_MSYSTEM_IS_SET HAVE_RTLGENRANDOM) - list(APPEND compat_SOURCES compat/mingw.c compat/winansi.c compat/win32/path-utils.c - compat/win32/pthread.c compat/win32mmap.c compat/win32/syslog.c - compat/win32/trace2_win32_process_info.c compat/win32/dirent.c - compat/nedmalloc/nedmalloc.c compat/strdup.c) + list(APPEND compat_SOURCES + compat/mingw.c + compat/winansi.c + compat/win32/flush.c + compat/win32/path-utils.c + compat/win32/pthread.c + compat/win32mmap.c + compat/win32/syslog.c + compat/win32/trace2_win32_process_info.c + compat/win32/dirent.c + compat/nedmalloc/nedmalloc.c + compat/strdup.c) set(NO_UNIX_SOCKETS 1) elseif(CMAKE_SYSTEM_NAME STREQUAL "Linux") -- cgit v1.2.3