Re: [zfs-discuss] Seagate Constellation vs. Hitachi Ultrastar
On Apr 6, 2012, at 4:58 PM, Marion Hakanson wrote: > a...@blackandcode.com said: >> I'm spec'ing out a Thumper-esque solution and having trouble finding my >> favorite Hitachi Ultrastar 2TB drives at a reasonable post-flood price. The >> Seagate Constellations seem pretty reasonable given the market circumstances >> but I don't have any experience with them. Anybody using these in their ZFS >> systems and have you had good luck? > > We have a lot of 2TB and 3TB Seagates here, they work fine. Most of > ours are the Nearline-SAS variety, in Dell MD1200 enclosures, used on > Windows & Linux behind PERC H800 RAID cards, and on Solaris-10 and > OpenIndiana behind LSI SAS HBA's. We do have one new server with a > pile of 2TB SATA Seagate's as well, so far working fine. > > The only caveat I've found is that the Nearline SAS Seagates go really > slow with the Solaris default multipath load-balancing setting > (round-robin). Set it to "none" or some large block value and they go > fast. This issue doesn't appear when used with the PERC H800's. We are starting to see a number of SAS HDDs that prefer logical-block to round-robin. I see this with late model Seagate and Toshiba HDDs. There is another, similar issue with recognition of multipathing by the scsi_vhci driver. Both of these are being tracked as https://www.illumos.org/issues/644 and there is an alternate scsi_vhci.conf file posted in that bugid. We're considering making logical-block the default (as in above bugid) and we have not discovered a reason to keep round-robin. If you know of any reason why round-robin is useful, please add to the bugid. -- richard -- ZFS Performance and Training richard.ell...@richardelling.com +1-760-896-4422 ___ zfs-discuss mailing list zfs-discuss@opensolaris.org http://mail.opensolaris.org/mailman/listinfo/zfs-discuss
Re: [zfs-discuss] What's wrong with LSI 3081 (1068) + expander + (bad) SATA disk?
I'm not familiar with the J4400 at all, but isn't Sun/Oracle using -like NetAPP- Interposer cards and thus handling the SATA drives more or less like SAS ones? Out of curiosity, are there any third-party hardware vendors that make server/storage chassis (Supermicro et al) who make SATA backplanes with the SAS interposers soldered on? Would that make sense, or be cheaper/more reliable than having extra junk between the disk and backplane connectors? (if I correctly understand what the talk is about? ;) ZFS was very attractive at first because of the claim that "it returns Inexpensive into raId" and can do miracles with SATA disks. Reality has shown to many of us that many SATA implementations existing in the wild should be avoided... so we're back to good vendors' higher end expensive SATAs or better yet SAS drives. Not inexpensive anymore again :( Thanks, //Jim ___ zfs-discuss mailing list zfs-discuss@opensolaris.org http://mail.opensolaris.org/mailman/listinfo/zfs-discuss
Re: [zfs-discuss] What's wrong with LSI 3081 (1068) + expander + (bad) SATA disk?
On Apr 7, 2012, at 4:15 PM, Jim Klimov wrote: >> I'm not familiar with the J4400 at all, but isn't Sun/Oracle using -like >> NetAPP- >> Interposer cards and thus handling the SATA drives more or less like SAS >> ones? > > Out of curiosity, are there any third-party hardware vendors > that make server/storage chassis (Supermicro et al) who make > SATA backplanes with the SAS interposers soldered on? None AFIAK. > > Would that make sense, or be cheaper/more reliable than > having extra junk between the disk and backplane connectors? > (if I correctly understand what the talk is about? ;) It would not be more reliable or cheaper. > ZFS was very attractive at first because of the claim that > "it returns Inexpensive into raId" and can do miracles > with SATA disks. Reality has shown to many of us that > many SATA implementations existing in the wild should > be avoided... so we're back to good vendors' higher end > expensive SATAs or better yet SAS drives. Not inexpensive > anymore again :( You can't get past the age-old idiom: you get what you pay for. In some cases today, depending on vendor, the cost of SATA + interposer is the same as SAS. -- richard -- DTrace Conference, April 3, 2012, http://wiki.smartos.org/display/DOC/dtrace.conf ZFS Performance and Training richard.ell...@richardelling.com +1-760-896-4422 ___ zfs-discuss mailing list zfs-discuss@opensolaris.org http://mail.opensolaris.org/mailman/listinfo/zfs-discuss
