From mboxrd@z Thu Jan 1 00:00:00 1970 From: bakul@bitblocks.com (Bakul Shah) Date: Mon, 23 Apr 2018 23:22:41 -0700 Subject: [TUHS] /dev/drum In-Reply-To: Your message of "Mon, 23 Apr 2018 22:59:19 -0600." References: <9a5e49bb-f235-4b87-445b-1532d8facd2f@update.uu.se> <20180424044941.7C703156E510@mail.bitblocks.com> Message-ID: <20180424062248.9D2FE156E510@mail.bitblocks.com> On Mon, 23 Apr 2018 22:59:19 -0600 Warner Losh wrote: > > ... > > Not_Zoned # Zone Mode <<== this seems wrong. > > > > That's right. This is for BIO_ZONE stuff, which has to do with host managed > and host aware SMR drive zones. That's different than the zones you are > talking about. Ah. Thanks! Does host management of SMR zones provide better throughput for sequential writes? Enough to make it worht it? [I guess this may be something you guys may care about?] Haven't had a chance to work on storage stuff for ages. [Last I played with Ceph was 5 years ago and at a higher level than disks.] > Yes. This matches our experience where we get 1.5x better on the low LBAs > than the high LBAs. We're looking to 'short stroke' the drive to the first > part of it to get better performance... Toss a filesystem on top of it, and > have a more random workload and it's down to about 30% better than using > the whole drive.... Is the tradeoff worth it? Now you have choices like Sata vs SAS vs SDD vs PCIe.... We've come a long way from /dev/drum :-)