Using O_DSYNC means we do not have to write out the inode if we are overwriting full allocated blocks. For sheepdog that is a fairly usual use case when blocks in an image has already been allocated and the guest OS overwrites previously deleted blocks with new data.
Signed-off-by: Christoph Hellwig <[email protected]> Index: sheepdog/sheep/journal.c =================================================================== --- sheepdog.orig/sheep/journal.c 2011-11-10 21:24:20.851800458 +0100 +++ sheepdog/sheep/journal.c 2011-11-10 21:24:29.227795709 +0100 @@ -65,7 +65,7 @@ static int jrnl_close(struct jrnl_descri static int jrnl_create(struct jrnl_descriptor *jd, const char *jrnl_dir) { snprintf(jd->path, sizeof(jd->path), "%sXXXXXX", jrnl_dir); - jd->fd = mkostemp(jd->path, O_SYNC); + jd->fd = mkostemp(jd->path, O_DSYNC); if (jd->fd < 0) { eprintf("failed to create %s: %m\n", jd->path); @@ -283,7 +283,7 @@ int jrnl_recover(const char *jrnl_dir) } if (!jrnl_has_end_mark(&jd)) goto end_while_2; - jd.target_fd = open(jd.head.target_path, O_SYNC | O_RDWR); + jd.target_fd = open(jd.head.target_path, O_DSYNC | O_RDWR); if (ret) { eprintf("unable to open the object file %s for recovery\n", jd.head.target_path); Index: sheepdog/sheep/store.c =================================================================== --- sheepdog.orig/sheep/store.c 2011-11-10 21:24:20.871799279 +0100 +++ sheepdog/sheep/store.c 2011-11-10 21:24:45.804065749 +0100 @@ -439,7 +439,7 @@ static int ob_open(uint32_t epoch, uint6 if (sys->use_directio && is_data_obj(oid)) flags = O_DIRECT | O_RDWR | aflags; else - flags = O_SYNC | O_RDWR | aflags; + flags = O_DSYNC | O_RDWR | aflags; snprintf(path, sizeof(path), "%s%08u/%016" PRIx64, obj_path, epoch, oid); @@ -482,7 +482,7 @@ int update_epoch_log(int epoch) dprintf("update epoch: %d, %d\n", epoch, sys->nr_nodes); snprintf(path, sizeof(path), "%s%08u", epoch_path, epoch); - fd = open(path, O_RDWR | O_CREAT | O_SYNC, def_fmode); + fd = open(path, O_RDWR | O_CREAT | O_DSYNC, def_fmode); if (fd < 0) { ret = fd; goto err_open; @@ -1008,7 +1008,7 @@ int set_cluster_ctime(uint64_t ct) { int fd, ret; - fd = open(config_path, O_SYNC | O_WRONLY); + fd = open(config_path, O_DSYNC | O_WRONLY); if (fd < 0) return -1; @@ -1310,7 +1310,7 @@ next: if (rsp->result == SD_RES_SUCCESS) { char path[PATH_MAX], tmp_path[PATH_MAX]; - int flags = O_SYNC | O_RDWR | O_CREAT; + int flags = O_DSYNC | O_RDWR | O_CREAT; snprintf(path, sizeof(path), "%s%08u/%016" PRIx64, obj_path, epoch, oid); @@ -2043,7 +2043,7 @@ int set_cluster_copies(uint8_t copies) { int fd, ret; - fd = open(config_path, O_SYNC | O_WRONLY); + fd = open(config_path, O_DSYNC | O_WRONLY); if (fd < 0) return SD_RES_EIO; @@ -2080,7 +2080,7 @@ int set_cluster_flags(uint16_t flags) { int fd, ret = SD_RES_EIO; - fd = open(config_path, O_SYNC | O_WRONLY); + fd = open(config_path, O_DSYNC | O_WRONLY); if (fd < 0) goto out; -- sheepdog mailing list [email protected] http://lists.wpkg.org/mailman/listinfo/sheepdog
