6.2 & Strange HDD problem - BSD

This is a discussion on 6.2 & Strange HDD problem - BSD ; On Thu, 2 Aug 2007 23:28:12 +0100, Steve O'Hara-Smith wrote: : Oh sure they can burst from the cache faster than that - but : sustained rates are way lower - more than 50MB/s is impressive. I get about 73-74MB/s ...

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Thread: 6.2 & Strange HDD problem

  1. Re: 6.2 & Strange HDD problem

    On Thu, 2 Aug 2007 23:28:12 +0100, Steve O'Hara-Smith wrote:
    : Oh sure they can burst from the cache faster than that - but
    : sustained rates are way lower - more than 50MB/s is impressive.

    I get about 73-74MB/s off a consumer grade WD drive (WDC3200AAKS),
    sustained read. Tad slower write but not much. This drive is a cheapo
    7400 (or 7200? don't remember) RPM drive, about $70 retail. Actually
    measured with 1GB, onboard ICH5, the stupid ICH5 stuck at SATA-I, and
    through the geom gmirror front end in raid 1 at that. No
    optimizations except a little tweak to vfs.readahead (?) to 16 instead
    of 8.


  2. Re: 6.2 & Strange HDD problem

    On Thu, 02 Aug 2007 20:42:31 +1000, Steve Adam
    wrote:


    >
    >Hi again, Glenn,
    >
    >The Promise card arrived today, and I installed it


    [CUT]

    >Both show a touch over 40MB/second on each drive while
    >synchronizing a mirror with no other system activity.
    >
    >Steve.


    Thank you very much, Steve.

    All of the above will be very useful for me, I'm evaluating a similar
    promise model.


  3. Re: 6.2 & Strange HDD problem

    In article <176uZD2KcidF-pn2-HbDKF95Phdid@rikki.tavi.co.uk>,
    Bob Eager wrote:
    >On Fri, 3 Aug 2007 01:32:45 UTC, bv@wjv.com (Bill Vermillion) wrote:
    >
    >> In article <176uZD2KcidF-pn2-ZJdIDqxstdwk@rikki.tavi.co.uk>,
    >> Bob Eager wrote:
    >> >On Thu, 2 Aug 2007 13:36:47 UTC, Steve O'Hara-Smith
    >> >wrote:
    >> >
    >> >> On Thu, 02 Aug 2007 20:42:31 +1000
    >> >> Steve Adam wrote:
    >> >>
    >> >> > Another point of interest is that the new card
    >> >> > did not show any performance difference that
    >> >> > I could see, though it's SATA 300 while the
    >> >> > other card is a 150.
    >> >>
    >> >> I don't think there exist any single drives that can produce data
    >> >> faster than SATA 150 can handle, a RAID array with a single SATA connection
    >> >> probably can.
    >> >
    >> >Surely they can deliver data from the cache faster than that?

    >>
    >> >--
    >> >Bob Eager
    >> >begin 123 a new life...take up Extreme Ironing!

    >>
    >> It's not the problem of delivering data from cache, but getting
    >> the data from the platter into the cache.

    >
    >You miss the point.
    >
    >The burst rate from the cache is higher, and that is what can exceed the
    >150kB/s.
    >
    >> Check the web-sites for you favorite drive, and go to the technical
    >> specs section and look for the data transfer rate from platter to
    >> cache.

    >
    >I'm perfectly aware of that, thank you. I never buy a disk without
    >reading (and understanding) its specs first.


    Then you and I are probably in the minority. Back when drives
    started getting faster all everyone could talk about was the
    7200RPM drives like the original Baracudda.

    But I measured an IBM drive rotating at 5400RPM that had a faster
    throughput than the 'cuddas.

    The reason was that the IBMs had a smaller head gap and were
    writing more data per track, and getting more bits of the platter
    at 5400RPM than the 'cuddas did at 7200RPM.

    So much of the raving about access time and RPMs came from those
    run MS systems that had synchronous writes and that's what
    DPT [a local company] started making caching controllers for
    MS machines.

    The previous year Steve, the owner, described the operation to me
    at a demo they had at a Comdex in Atlanta. There were about
    20 Wyse50 terminal spewing data to the screen faster than I had
    ever seen on any multi-terminal system. The system was
    a Heuricon - a company that was making their own Unix machines
    along with close to 100 manufacturers - all with slightly different
    versions of Unix. Sort of like the Linux world today :-(

    Those were really interesting days.

    Bill
    >
    >--
    >Bob Eager
    >begin 123 a new life...take up Extreme Ironing!



    --
    Bill Vermillion - bv @ wjv . com

  4. Re: 6.2 & Strange HDD problem

    Steve Adam wrote:
    > Glenn Middleton wrote:
    >> wrote:
    >>
    >>> I have arranged to buy a Promise SATA300 TX4 which
    >>> has 4 ports, no RAID, and seems reasonably priced.
    >>>
    >>> I'll let you know how it goes, after it arrives.

    >> Many thanks, Steve..

    >
    > Hi again, Glenn,


    And again...

    Just to let you know... Though the promise card
    does seem more reliable than the adaptec, the
    TX4 does have errors at times. I haven't seen
    any problems during normal system activity (which
    is very light on this system) but the following
    sequence of commands resulted in a timeout within
    about 2 minutes.

    # dd if=/dev/ad4 of=/dev/null &
    # dd if=/dev/ad6 of=/dev/null &
    # find / | wc&
    # find / | wc&
    # find / | wc&
    # find / | wc&

    ad4: TIMEOUT - READ_DMA retrying (1 retry left) LBA=171247
    ad4: WARNING - SETFEATURES SET TRANSFER MODE taskqueue timeout - completing request directly
    ad4: WARNING - SETFEATURES SET TRANSFER MODE taskqueue timeout - completing request directly
    ad4: WARNING - SETFEATURES ENABLE RCACHE taskqueue timeout - completing request directly
    ad4: WARNING - SETFEATURES ENABLE WCACHE taskqueue timeout - completing request directly
    ad4: WARNING - SET_MULTI taskqueue timeout - completing request directly
    ad4: TIMEOUT - READ_DMA retrying (1 retry left) LBA=567230
    ad4: TIMEOUT - READ_DMA retrying (1 retry left) LBA=585491
    ad6: WARNING - SETFEATURES SET TRANSFER MODE taskqueue timeout - completing request directly
    ad6: WARNING - SETFEATURES SET TRANSFER MODE taskqueue timeout - completing request directly
    ad6: WARNING - SETFEATURES ENABLE RCACHE taskqueue timeout - completing request directly
    ad6: WARNING - SETFEATURES ENABLE WCACHE taskqueue timeout - completing request directly
    ad6: WARNING - SET_MULTI taskqueue timeout - completing request directly
    ad6: TIMEOUT - READ_DMA retrying (1 retry left) LBA=1327372
    ad6: TIMEOUT - READ_DMA retrying (1 retry left) LBA=255625419
    ad6: WARNING - SETFEATURES SET TRANSFER MODE taskqueue timeout - completing request directly
    ad6: WARNING - SETFEATURES SET TRANSFER MODE taskqueue timeout - completing request directly
    ad6: WARNING - SETFEATURES ENABLE RCACHE taskqueue timeout - completing request directly
    ad6: WARNING - SETFEATURES ENABLE WCACHE taskqueue timeout - completing request directly
    ad6: WARNING - SET_MULTI taskqueue timeout - completing request directly
    ad6: TIMEOUT - READ_DMA48 retrying (1 retry left) LBA=304159067
    ad6: WARNING - READ_DMA48 UDMA ICRC error (retrying request) LBA=304159067
    ad6: FAILURE - READ_DMA48 timed out LBA=304159067
    GEOM_MIRROR: Request failed (error=5). ad6[READ(offset=155729442304, length=2048)]
    GEOM_MIRROR: Device gm0: provider ad6 disconnected.








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