Re: 20TB Storage System (fsck????)

From: Brooks Davis (brooks_at_one-eyed-alien.net)
Date: 09/03/03

  • Next message: Geoff Buckingham: "Re: 20TB Storage System" 
    Date: Wed, 3 Sep 2003 12:47:34 -0700
To: Chuck Swiger <cswiger@mac.com>

    On Wed, Sep 03, 2003 at 03:37:35PM -0400, Chuck Swiger wrote:
    > Piotr KUCHARSKI wrote:
    > >On Wed, Sep 03, 2003 at 02:37:50PM -0400, Chuck Swiger wrote:
    > >>I'm wary of the write-performance hit from putting too many drives wide
    > >>in a RAID-5 (or -5,0) configuration.
    > >
    > >How many is "too many"?
    >
    > At one point, the advice used to be to use between four and seven disks for
    > a RAID-5 volume. For example, the Apple XServe RAID box has 14 bays, but
    > Apple seems to recommend configuring it as two 7-drive RAID-5 volumes,
    > rather than a single 14-drive-wide RAID-5 volume.

    As far as I can tell from taking one of ours apart, that's not
    recommendation, that's a hard limit due to the system design. The
    XServe RAID is two 100% independent 7-disk RAID systems. If you look at
    the controller boards, each one has four High-Point ATA controllers which
    means it can only access 8 disks with reasonable performance. There
    appears to be no communication between the halves of the systems.

    -- Brooks 

    -- 
Any statement of the form "X is the one, true Y" is FALSE.
PGP fingerprint 655D 519C 26A7 82E7 2529  9BF0 5D8E 8BE9 F238 1AD4

  • Next message: Geoff Buckingham: "Re: 20TB Storage System"

    Relevant Pages

    • Re: Storage server advice
      ... > wondering if anyone could offer me some advice based on their experience. ... As for getting the server and storage, that isn't terribly hard, just ... with SCSI disks is an entirely different level of financial pain than 1 ... terabyte with IDE disks.) ...
      (comp.os.linux.hardware)
    • Re: [opensuse] Best Disk Layout
      ... starting from new disks, new everything. ... In searching the Net for advice on an optimum disk layout, ...
      (SuSE)
    • Re: [opensuse] Best Disk Layout
      ... In searching the Net for advice on an optimum disk layout, ... Given that space will not be a problem of itself (two SATA 320 GB disks, ... With LVM there's never reason to re-partition anymore. ...
      (SuSE)
    • [opensuse] Best Disk Layout
      ... My old desktop computer died in such a way that I'm faced with complete reinstallon its replacement, multi-boot including openSuSE 10.2, starting from new disks, new everything. ... In searching the Net for advice on an optimum disk layout, all I've succeeded in doing is confuse myself in trying to come to terms with the often contradictory advice out there. ... What are the plusses and minuses involved (a lot of Net afficionados refer to these but don't explain what they are)? ...
      (SuSE)
    • Re: Avoiding Carotid Artery Surgery
      ... Looking forward to reading and using it. ... I'm checking out this group upon advice from you and this looks like my kind of place! ... <I am also into fasting for health.> ... Did you know that nicotine can be harmful to the disks in your back because it decreases the ability of the disks to absorb nutrients they need to stay healthy, and may cause them to become dry and brittle? ...
      (misc.health.alternative)