On Fri 13-05-16 12:29:10, Jens Axboe wrote: > Thanks Jan, this is great and super useful! I'm revamping certain parts of > it to deal with write back caching better, and I'll take a look at the > regressions that you reported. > > What kind of SSD is this? I'm assuming it's SATA (QD=32), and then it would > probably be a safe assumption that it's flagging itself as having a volatile > write back cache, would that be a correct assumption? Yes, it is SATA with writeback cache. > Are you using scsi-mq, or do you have an IO scheduler attached to it? The disk was using IO scheduler, however at this point I'm not 100% sure which scheduler (deadline or cfq) was the default one for the distro that was installed. The machine is currently testing something else so I cannot reinstall it and check. Maybe I can rerun some tests later in the week when the machine gets freed with scsi-mq or deadline IO scheduler so that we have 100% certain config. Honza -- Jan Kara <jack@xxxxxxxx> SUSE Labs, CR -- To unsubscribe from this list: send the line "unsubscribe linux-fsdevel" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html