[SATLUG] I/O Questions

[Eli]

Strange.  It sure seems like the cpu is taking a beating during ordinary
disk usage.

I use this to get some relative numbers for i/o:

http://sourceforge.net/projects/tiobench/

It executes multiple simultaneous reads/writes and gives a nice little
report at the end. Perhaps it will create a picture of what's going on
with cpu usage & i/o.

I'm thinking that you're not really getting dma transfers.

~e





> On 7/22/05, Eli <eli at then7.com> wrote:
>> is dma turned on for the 120gb ata?
>>
>> ~e
>>
>>
>> > The problems I run into is during tape operations, or heavy harddrive
>> > use.  During these times, the system becomes sluggish
>
> Eli,
>
> Even though hdparm says it's off, it still shows up as using udma5.
>
>
>
> nightscape ~ # hdparm -i /dev/hda
>
> /dev/hda:
>
>  Model=WDC WD1200JB-00EVA0, FwRev=15.05R15, SerialNo=WD-WMAEL2257862
>  Config={ HardSect NotMFM HdSw>15uSec SpinMotCtl Fixed DTR>5Mbs FmtGapReq
> }
>  RawCHS=16383/16/63, TrkSize=57600, SectSize=600, ECCbytes=74
>  BuffType=DualPortCache, BuffSize=8192kB, MaxMultSect=16, MultSect=16
>  CurCHS=16383/16/63, CurSects=16514064, LBA=yes, LBAsects=234441648
>  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
>  AdvancedPM=no WriteCache=enabled
>  Drive conforms to: device does not report version:
>
>  * signifies the current active mode
>
> nightscape ~ # hdparm /dev/hda
>
> /dev/hda:
>  multcount    = 16 (on)
>  IO_support   =  0 (default 16-bit)
>  unmaskirq    =  0 (off)
>  using_dma    =  0 (off)
>  keepsettings =  0 (off)
>  readonly     =  0 (off)
>  readahead    = 256 (on)
>  geometry     = 16383/255/63, sectors = 234441648, start = 0
>