On Tue, Feb 15, 2005 at 08:03:39PM +0300, E.Rodichev wrote:
> On Tue, 15 Feb 2005, Magnus Hagander wrote:
> >Question 1: Is your writeback cache really disabled in Linux, on the
> >harddrive? Windows fsync will *write through the disk write cache* if
> >the driver is properly implemented. AFAIK, on Linux if write cache is
> >enabled on the drive, fsync will only get into the cache.
>
> Difficult to say concerning writeback cache... I have 2.6.10 without any
> additional tuning, file system is ext2. From dmesg:
>
> hda: TOSHIBA MK8026GAX, ATA DISK drive
> hda: max request size: 128KiB
> hda: 156301488 sectors (80026 MB), CHS=65535/16/63, UDMA(100)
> hda: cache flushes supported

Write caching is generally on by default with IDE drives. Disable it
like so:
hdparm -W 0 /dev/hda

-Mike Adler

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