Merge branch 'ns/batch-fsync'

Introduce a filesystem-dependent mechanism to optimize the way the
bits for many loose object files are ensured to hit the disk
platter.

* ns/batch-fsync:
  core.fsyncmethod: performance tests for batch mode
  t/perf: add iteration setup mechanism to perf-lib
  core.fsyncmethod: tests for batch mode
  test-lib-functions: add parsing helpers for ls-files and ls-tree
  core.fsync: use batch mode and sync loose objects by default on Windows
  unpack-objects: use the bulk-checkin infrastructure
  update-index: use the bulk-checkin infrastructure
  builtin/add: add ODB transaction around add_files_to_cache
  cache-tree: use ODB transaction around writing a tree
  core.fsyncmethod: batched disk flushes for loose-objects
  bulk-checkin: rebrand plug/unplug APIs as 'odb transactions'
  bulk-checkin: rename 'state' variable and separate 'plugged' boolean

1 files changed, 11 insertions, 1 deletions

diff --git a/cache.h b/cache.h
index 595582becc..7b3825cf50 100644
--- a/cache.h
+++ b/cache.h
@@ -1031,6 +1031,10 @@ enum fsync_component {
 			      FSYNC_COMPONENT_INDEX | \
 			      FSYNC_COMPONENT_REFERENCE)
 
+#ifndef FSYNC_COMPONENTS_PLATFORM_DEFAULT
+#define FSYNC_COMPONENTS_PLATFORM_DEFAULT FSYNC_COMPONENTS_DEFAULT
+#endif
+
 /*
  * A bitmask indicating which components of the repo should be fsynced.
  */
@@ -1040,7 +1044,8 @@ extern int use_fsync;
 
 enum fsync_method {
 	FSYNC_METHOD_FSYNC,
-	FSYNC_METHOD_WRITEOUT_ONLY
+	FSYNC_METHOD_WRITEOUT_ONLY,
+	FSYNC_METHOD_BATCH,
 };
 
 extern enum fsync_method fsync_method;
@@ -1766,6 +1771,11 @@ void fsync_or_die(int fd, const char *);
 int fsync_component(enum fsync_component component, int fd);
 void fsync_component_or_die(enum fsync_component component, int fd, const char *msg);
 
+static inline int batch_fsync_enabled(enum fsync_component component)
+{
+	return (fsync_components & component) && (fsync_method == FSYNC_METHOD_BATCH);
+}
+
 ssize_t read_in_full(int fd, void *buf, size_t count);
 ssize_t write_in_full(int fd, const void *buf, size_t count);
 ssize_t pread_in_full(int fd, void *buf, size_t count, off_t offset);