[libvirt] [PATCH 2/2] fsync new storage volumes even if new volume was copied.

Originally the storage volume files were opened with O_DSYNC to make sure they were flushed to disk immediately. It turned out that this was extremely slow in some cases, so the O_DSYNC was removed in favor of just calling fsync() after all the data had been written. However, this call to fsync was inside the block that is executed to zero-fill the end of the volume file. In cases where the new volume is copied from an old volume, and they are the same length, this fsync would never take place. Now the fsync is *always* done, unless there is an error (in which case it isn't important, and is most likely inappropriate. --- src/storage/storage_backend.c | 13 +++++++------ 1 files changed, 7 insertions(+), 6 deletions(-) diff --git a/src/storage/storage_backend.c b/src/storage/storage_backend.c index 1eb8e33..730ca7b 100644 --- a/src/storage/storage_backend.c +++ b/src/storage/storage_backend.c @@ -324,12 +324,13 @@ static int createRawFileOpHook(int fd, void *data) { } } - if (fsync(fd) < 0) { - ret = errno; - virReportSystemError(errno, _("cannot sync data to file '%s'"), - hdata->vol->target.path); - goto cleanup; - } + } + + if (fsync(fd) < 0) { + ret = errno; + virReportSystemError(errno, _("cannot sync data to file '%s'"), + hdata->vol->target.path); + goto cleanup; } cleanup: -- 1.7.1.1