Re: Very slow writing to SATA disk

From: Peter Jeremy (PeterJeremy_at_optushome.com.au)
Date: 10/28/05

  • Next message: Robert Watson: "Re: RFC: porting NetBSD fsdb enhancements to FreeBSD" 
    Date: Fri, 28 Oct 2005 19:48:44 +1000
To: "Mikhail T." <mi@aldan.algebra.com>

    On Fri, 2005-Oct-28 01:18:03 -0400, Mikhail T. wrote:
    >I've got a new Hitachi drive with 16Mb of cache:
    >
    > ad8: 476940MB <HDS725050KLA360 K2AOA11A> at ata4-master SATA150
    >
    >and am trying to use it to store backups online. Unfortunately, writing
    >to the disk is painfully slow (by today's standards) -- it can barely
    >keep 7Mb/second and my other (SCSI) disks run circles around it.

    If this drive doesn't support tagged-queueing, is the write cache
    disabled? I get that sort of performance from a (PATA) disk with
    the cache disabled (hw.ata.wc="0" in loader.conf)

    >According to smartctl, the drive runs at 56C during the copying. Its
    >idle temperature seems to be 54C.

    I'd double-check that (eg with a finger). If the drive really is
    running at 56°C, it won't last very long. 

    -- 
Peter Jeremy
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  • Next message: Robert Watson: "Re: RFC: porting NetBSD fsdb enhancements to FreeBSD"

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