> So question is : why when i am copying file from one HD to another (for
> simplicity from /hda to /hdb)
> the speed fall down ? Starting from about 27-30 MB/s (drives are in UDMA-4,
> hdparm -X68) it drops
> down to 11-12 MB/s after 4-5s. In *indows transfer rate is almost constant
> and about 20-22 MB/s (same hardware). Why the h#ll we suck?
> I feel that it's due to buffer cache, because when you use sync (while
> copying) transfer rate is so small or even 0.
> Drives are tuned with hdparm to highest transfer rates, readahead, multiple
> sector count (hdparm
> for details).
> Tried different filesystems, from classic ext2/3 to modern xfs/reiserfs. The
> same results.
> Pure kernel from kernel.org (2.4.{19,20,21}), vendors kernels - all the
How do you copy files? cp? dd? Midnight Commander? ;)
Does it happen with SCSI?
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vda