Hello Geoff,
Thanks Mark for doing a great job while I was doing other stuff.
On Wed, 21 Mar 2001 quintaq@yahoo.co.uk wrote:
> The result of hdparm -tT /dev/hda was, however, exactly the same as
> before (ie circa 15 MB/sec. The results for /dev/hda7 remain at about
> 30 MB/sec.
You may get a burst because of caching prefetch or predictive readahead,
but that is artifical; however, in your case the root directory begins 25%
in the drive.
/sbin/hdparm -t /dev/hda2 /dev/hda5 /dev/hda6 /dev/hda7 /dev/hda8 /dev/hda9 /dev/hda10
/dev/hda2:
Timing buffered disk reads: 64 MB in 1.80 seconds = 35.56 MB/sec
/dev/hda5:
Timing buffered disk reads: 64 MB in 1.85 seconds = 34.59 MB/sec
/dev/hda6:
Timing buffered disk reads: 64 MB in 1.90 seconds = 33.68 MB/sec
/dev/hda7:
Timing buffered disk reads: 64 MB in 1.95 seconds = 32.82 MB/sec
/dev/hda8:
Timing buffered disk reads: 64 MB in 1.95 seconds = 32.82 MB/sec
/dev/hda9:
Timing buffered disk reads: 64 MB in 2.13 seconds = 30.05 MB/sec
/dev/hda10:
Timing buffered disk reads: 64 MB in 2.13 seconds = 30.05 MB/sec
Disk /dev/hda: 255 heads, 63 sectors, 3737 cylinders
Units = cylinders of 16065 * 512 bytes
Device Boot Start End Blocks Id System
/dev/hda1 * 1 7 56196 83 Linux
/dev/hda2 8 269 2104515 83 Linux
/dev/hda3 270 3737 27856710 5 Extended
/dev/hda5 270 661 3148708+ 83 Linux
/dev/hda6 662 923 2104483+ 83 Linux
/dev/hda7 924 1119 1574338+ 83 Linux
/dev/hda8 1120 1642 4200966 83 Linux
/dev/hda9 1643 1773 1052226 83 Linux
/dev/hda10 1774 3737 15775798+ 83 Linux
> Further, even though the relevant line was commented out of fstab, I
> could still perform hdparm -tT /dev/hda1 (giving the usual 15 MB/sec).
> I suppose that this is because fdisk still showed :
>
> Disk /dev/hda: 255 heads, 63 sectors, 3737 cylinders
> Units = cylinders of 16065 * 512 bytes
>
> Device Boot Start End Blocks Id System
> /dev/hda1 * 1 932 7486258+ b Win95 FAT32
> /dev/hda2 933 3737 22531162+ 5 Extended
> /dev/hda5 933 935 24066 83 Linux
> /dev/hda6 936 952 136521 82 Linux swap
> /dev/hda7 953 3737 22370481 83 Linux
First you have the faster portion of the drive using a lame OS, so do not
expect Linux to perform if you put it on the slowest portions of the
device.
> On the other hand, am I correct in interpreting the bonnie output for
> the block read (included in my earlier post), of 20937 KB/sec as
> reasonably healthy for my DTLA (ie consistent with hdparm's 30 MB/sec),
> when performing more realistic tasks on the linux filesystem ?
Yes if you adjust for ZONES.
[root@via DiskPerf-1.0.3]# ./DiskPerf /dev/hda
Device: IBM-DTLA-307030 Serial Number: YKDYKM37674
LBA 0 DMA Read Test = 56.53 MB/Sec (4.42 Seconds)
Outer Diameter Sequential DMA Read Test = 35.47 MB/Sec (7.05 Seconds)
Inner Diameter Sequential DMA Read Test = 17.74 MB/Sec (14.09 Seconds)
As you can clearly see a single sector v/s outer v/s inner zones produce
different transfer throughputs.
> Regards,
>
> Geoff
Andre Hedrick
Linux ATA Development
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This archive was generated by hypermail 2b29 : Fri Mar 23 2001 - 21:00:16 EST