Note: "permalinks" may not be as permanent as we would like,
direct links of old sources may well be a few messages off.
Phil Frost writes: > Unfortunately, I don't feel very qualified in this area, so can anyone > tell me if I'm totally off base here? Any suggestions on how I might > test this? I don't know much about the kernel myself, but your post suggested a fix. I applied the patch below to linux-3.4.1 and this patch appears to fix the problem. Specifically, fsync() is too fast before the patch, and it runs at non-drbd speed after the patch. diff --git a/drivers/block/drbd/drbd_main.c b/drivers/block/drbd/drbd_main.c index 211fc44..96e400b 100644 --- a/drivers/block/drbd/drbd_main.c +++ b/drivers/block/drbd/drbd_main.c @@ -3413,6 +3413,7 @@ struct drbd_conf *drbd_new_device(unsigned int minor) set_disk_ro(disk, true); disk->queue = q; + blk_queue_flush(disk->queue, REQ_FLUSH | REQ_FUA); disk->major = DRBD_MAJOR; disk->first_minor = minor; disk->fops = &drbd_ops;