Disk I/O - too slow?

[Don Levey]

On Mon, 2004-02-23 at 22:30, James Drabb wrote:
> On Mon, 2004-02-23 at 20:30, Don Levey wrote:
> > So...  I've got DMA enabled, Multiple I/O, EIDE 32-bit and lookahead
> > enabled in my /etc/sysconfig/harddisks file.  Running that hdparm line
> > gives me:
> > 
> > /dev/hdb: 
> > Timing buffer-cache reads:   1204 MB in  2.00 seconds = 601.49 MB/sec
> > Timing buffered disk reads:   96 MB in  3.00 seconds =  31.97 MB/sec
> > 
> > ...clearly *not* fast.  This is a Maxtor Diamond ATA 120Gb drive,
> > 7200rpm, on an ASUS A7V8X-X mb.  I'm running FC1 with a 2.6.3 kernel
> > from kernel.org.  Any suggestions for speeding up my I/O (or more info
> > to provide)?
> > 
> > TIA,  -Don
> 
> Those numbers are pretty respectable.  The 31.97 MB/sec sounds about
> right for your average 7200 RPM hard drive.  On all the standard 7200
> RPM drives I have, I get from 30 MB/s to 35 MB/s.  YOu need sata or scsi
> if you want more then that.
> 
> Here is my laptop:
> 
> /dev/hda:
>  Timing buffer-cache reads:   1500 MB in  2.00 seconds = 750.00 MB/sec
>  Timing buffered disk reads:   68 MB in  3.06 seconds =  22.22 MB/sec
>                                                                                           The first result is dependent on your memory speed. If I put the same hard drive in a system with slower memory, the first result will drop way down.  I have PC2100 in my laptop.  The second result is low because this laptop has a 4200 RPM drive.
> 
> What output do you get from:
>     hdparm -i /dev/hda
> and:
>     hdparm /dev/hda


Ah, of course: scsi vs eide.  The original numbers I was comparing to
were from a scsi drive.  The output I get is:

[root at dauphin root]# hdparm -i /dev/hdb

/dev/hdb:

 Model=Maxtor 6Y120L0, FwRev=YAR41BW0, SerialNo=Y3L5FTZE
 Config={ Fixed }
 RawCHS=16383/16/63, TrkSize=0, SectSize=0, ECCbytes=57
 BuffType=DualPortCache, BuffSize=2048kB, MaxMultSect=16, MultSect=16
 CurCHS=16383/16/63, CurSects=16514064, LBA=yes, LBAsects=240121728
 IORDY=on/off, tPIO={min:120,w/IORDY:120}, tDMA={min:120,rec:120}
 PIO modes:  pio0 pio1 pio2 pio3 pio4
 DMA modes:  mdma0 mdma1 mdma2
 UDMA modes: udma0 udma1 udma2 udma3 udma4 udma5 *udma6
 AdvancedPM=yes: disabled (255) WriteCache=enabled
 Drive conforms to: (null):

 * signifies the current active mode

[root at dauphin root]# hdparm  /dev/hdb

/dev/hdb:[root at dauphin root]# hdparm -i /dev/hdb

/dev/hdb:

 Model=Maxtor 6Y120L0, FwRev=YAR41BW0, SerialNo=Y3L5FTZE
 Config={ Fixed }
 RawCHS=16383/16/63, TrkSize=0, SectSize=0, ECCbytes=57
 BuffType=DualPortCache, BuffSize=2048kB, MaxMultSect=16, MultSect=16
 CurCHS=16383/16/63, CurSects=16514064, LBA=yes, LBAsects=240121728
 IORDY=on/off, tPIO={min:120,w/IORDY:120}, tDMA={min:120,rec:120}
 PIO modes:  pio0 pio1 pio2 pio3 pio4
 DMA modes:  mdma0 mdma1 mdma2
 UDMA modes: udma0 udma1 udma2 udma3 udma4 udma5 *udma6
 AdvancedPM=yes: disabled (255) WriteCache=enabled
 Drive conforms to: (null):

 * signifies the current active mode

[root at dauphin root]# hdparm  /dev/hdb

/dev/hdb:
 multcount    = 16 (on)
 IO_support   =  1 (32-bit)
 unmaskirq    =  1 (on)
 using_dma    =  1 (on)
 keepsettings =  0 (off)
 readonly     =  0 (off)
 readahead    = 256 (on)
 geometry     = 65535/16/63, sectors = 240121728, start = 0

 multcount    = 16 (on)
 IO_support   =  1 (32-bit)
 unmaskirq    =  1 (on)
 using_dma    =  1 (on)
 keepsettings =  0 (off)
 readonly     =  0 (off)
 readahead    = 256 (on)
 geometry     = 65535/16/63, sectors = 240121728, start = 0

I've been looking for performance tweaks, as certain things seem a bit
slow, such as I/O and display.  I had gotten a hot display card, for
example, from ATI on the basis of their having Linux drivers - only to
find that those drivers are... incomplete.  I was hoping to make up some
speed at disk level.  Oh well.
Thanks again,
 -Don