Re: ZFS or UFS? Solaris 11 or better stay with Solaris 10?

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Date: Thu, 29 Mar 2012 09:41:24 +0200
Message-ID: <>

Hi Tony,
  • regarding UFS vs ZFS. The best thing is to do any (!) sort of tests. But if you really cannot do This is really difficult question since:
    • zfs is brand new filesystem which will be improved more and more. UFS will not be improved.
      • but does it matter for you if you will keep this system for years without change ?
    • zfs has much more features which are unknown for UFS (and never will be)
      • but do you really need them ?
    • if you insist on using ZFS for Oracle read the following URL:
    • there are a lot of knowledge (in terms of people experience) in the internet about using UFS + Oracle
    • if you can do any sort of tests (ZFS vs UFS):
      • you can do it on both ZFS and UFS using:
        • Orion (Oracle tool to test storage performance)
          • of course don't relay on just one tool and its results
        • Oracle 11 IO calibration (new feature) and just compare the results
    • a couple of URLs:
  • regarding Solaris 10 vs 11
    • Solaris 11 has many new features. You can read WPs about What's new, etc. It's worth reading.
      • but do you need them for typical OLTP (DSS ?) environment ?
    • Solaris 10 is stable and predictable
      • but does it matter for you ? Maybe you like new environments ? New features ?
      • having Solaris 10 does not mean that you cannot upgrade to Solaris 11 in the future. Live Upgrade is a feature which helps you in this area.
    • if you happen to have a bug in Solaris 11 Oracle support is not known to be the best on this planet regarding fixing new bugs ...
  • regarding SAN

Best regards
Przemyslaw Bak (przemol)


On Wed, Mar 28, 2012 at 11:34:25PM +1000, De DBA wrote:

> G'day,
> I'm involved in a project to migrate a 4TB database from HP/UX 11 and Oracle 9i to a brand-new Sun M5000 server with Oracle This database suffers insert transactions in the order of 70 tx/sec. The daily redo production is in the order of 45GB. Management reports are also run with great vigour (i.e. large volumes of disk read IOPS). Two further tiny instances (5-7GB each) also live in the same environment.
> The original plan was to install Solaris 10 on the new server and create a big ZFS pool on the san, as proposed by Oracle Sales. However, doubts have arisen as to the performance of ZFS with Oracle databases, and we now lean towards using UFS for the database files. All discussions and white papers that I have been able to find on the subject stress to closely follow the upgrade path, as ZFS is continuously being improved still. Some blogs give pointers on how to make ZFS perform "almost the same as UFS", which sounds to me as a lot of extra effort for no gain. I struggle to find any validation for choosing ZFS over UFS.
> Today, the boss was told by a relation who used to work for Sun that that relation would no longer install boxes with UFS. He would also enable direct IO instead of totally relying on ZFS. The SAN disks should according to this relation be presented as raw disks, rather than striped-and-mirrored LUNs, to be RAIDed in ZFS. Apparently there are desirable features in ZFS that make this worthwhile. It should be noted that the SAN is (almost) completely dedicated to this one database machine and has block copy capabilities, built-in raid, etc.
> To me it seems a bit back-to-front to disable the SAN functionality, effectively turning it into an expensive external disk array, and at the same time shifting all the work that the SAN would have done to the database machine CPU where it competes for resources with the Oracle instances. What advantages, if any, exist that make using ZFS in this way is preferable over UFS? Do you have any experience with it?
> The Solaris version was bought before Oracle certified on Solaris 11, but now it seems silly not to upgrade Solaris before this system goes life. It will quite possibly not be able to be upgraded any time soon, possibly not until after Oracle 14x is released.. ;) The same relation however also insisted that "there are certification issues with Solaris 11" and he would never install Oracle 11g database on Solaris 11. However, MOS clearly shows that is fully certified on Solaris 11. Do you happen to know what issues could exist that pre-empt the use of Solaris 11, even if that might mean that the client will be on Solaris 10 for the next decade?
> I would like to hear about your experiences and thoughts.
> Cheers,
> Tony
> --
Received on Thu Mar 29 2012 - 02:41:24 CDT

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