Re: SCSI adaptec 19160 speed - 2.6.14-rt13 - Q for scsi experts

["art" <art@usfltd.com>]

Re: SCSI adaptec 19160 speed - 2.6.14-rt13 - Q for scsi experts

On Tue, Nov 29, 2005 at 07:36:44PM -0600, art wrote:
> > SCSI adaptec 19160 speed - 2.6.14-rt13 - Q for scsi experts
> >
> > Attached scsi disk sda at scsi0, channel 0, id 1, lun 0
> >   Vendor: COMPAQ    Model: BF14688286        Rev: HPB3
> >   Type:   Direct-Access                      ANSI SCSI revision: 03
> > scsi0:A:2:0: Tagged Queuing enabled.  Depth 64
> > target0:0:2: Beginning Domain Validation
> > target0:0:2: wide asynchronous.
> > target0:0:2: FAST-80 WIDE SCSI 160.0 MB/s DT (12.5 ns, offset 63)
> > target0:0:2: Ending Domain Validation
> > SCSI device sdb: 286749488 512-byte hdwr sectors (146816 MB)
> > SCSI device sdb: drive cache: write through
> > SCSI device sdb: 286749488 512-byte hdwr sectors (146816 MB)
> > SCSI device sdb: drive cache: write through
> > sdb: sdb1
> > Attached scsi disk sdb at scsi0, channel 0, id 2, lun 0
> >   Vendor: COMPAQ    Model: BF14688286        Rev: HPB3
> >   Type:   Direct-Access                      ANSI SCSI revision: 03
> > scsi0:A:5:0: Tagged Queuing enabled.  Depth 64
> > target0:0:5: Beginning Domain Validation
> > target0:0:5: wide asynchronous.
> > target0:0:5: FAST-80 WIDE SCSI 160.0 MB/s DT (12.5 ns, offset 63)
> > target0:0:5: Ending Domain Validation
> > SCSI device sdc: 286749488 512-byte hdwr sectors (146816 MB)
> > SCSI device sdc: drive cache: write through
> > SCSI device sdc: 286749488 512-byte hdwr sectors (146816 MB)
> > SCSI device sdc: drive cache: write through
> > sdc: sdc1
> > Attached scsi disk sdc at scsi0, channel 0, id 5, lun 0
> >
> > # hdparm -tT /dev/sdb
> > /dev/sdb:
> > Timing cached reads:   2316 MB in  2.00 seconds = 1157.90 MB/sec
> > Timing buffered disk reads:  268 MB in  3.00 seconds =  89.26 MB/sec
> > # hdparm -tT /dev/sdc
> >
> > /dev/sdc:
> > Timing cached reads:   2512 MB in  2.00 seconds = 1255.49 MB/sec
> > Timing buffered disk reads:  268 MB in  3.00 seconds =  89.32 MB/sec
> >
> > # hdparm -tT /dev/sdb & hdparm -tT /dev/sdc &
> > [1] 3314
> > [2] 3315
> >
> > /dev/sdb:
> > /dev/sdc:
> > Timing cached reads:    Timing cached reads:   1228 MB in  2.00 seconds = 613.88 MB/sec
> > 1316 MB in  1.99 seconds = 659.73 MB/sec
> > Timing buffered disk reads:   Timing buffered disk reads:
> > 174 MB in  3.00 seconds =  57.91 MB/sec
> > 170 MB in  3.05 seconds =  55.75 MB/sec
> > ------------------------------------------------------------------------------------------
> >
> > pci is 66Mhz theoretical throuhput ~ 250MB/s

And pci at 33mhz can do 130MB/s or so.  With a bit over overhead those
numbers sure look awful close to what a 33mhz pci bus can handle.

> > controller adaptec asc-19160
> > discs are 146GB-15krpm-cheetah
> >
> > one disc transfer 89MB/s
> >
> > adaptec speed with 2 disc on one channel = 57.91+55.75 = 113.66MB/s
> >
> > 71% of 160MB/s channel speed i expected ~90%
> >
> > any clue?

PCI bus not at 66mhz perhaps?  Is it an add in card on onboard?  I
wonder if a pci bus that supports 66mhz has to drop everything to 33mhz
if any of the cards installed are 33mhz only.  Having never tried I
don't know.

Len Sorensen

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# /sbin/lspci -v

02:00.0 SCSI storage controller: Adaptec AIC-7892B U160/m (rev 02)
        Subsystem: Adaptec 19160 Ultra160 SCSI Controller
        Flags: bus master, 66Mhz, medium devsel, latency 32, IRQ 16
        BIST result: 00
        I/O ports at a000 [disabled] [size=256]
        Memory at e302a000 (64-bit, non-prefetchable) [size=4K]
        [virtual] Expansion ROM at 50000000 [disabled] [size=128K]
        Capabilities: [dc] Power Management version 2

02:02.2 USB Controller: NEC Corporation USB 2.0 (rev 04) (prog-if 20 [EHCI])
        Subsystem: Belkin Root Hub
        Flags: bus master, medium devsel, latency 32, IRQ 16
        Memory at e3028000 (32-bit, non-prefetchable) [size=256]
        Capabilities: [40] Power Management version 2

02:04.0 FireWire (IEEE 1394): Texas Instruments TSB43AB23 IEEE-1394a-2000 Controller (PHY/Link) (prog-if 10 [OHCI])
        Subsystem: Adaptec: Unknown device 0030
        Flags: bus master, medium devsel, latency 32, IRQ 16
        Memory at e302b000 (32-bit, non-prefetchable) [size=2K]
        Memory at e3020000 (32-bit, non-prefetchable) [size=16K]
        Capabilities: [44] Power Management version 2


3 cards on same 16-int  Adaptec 19160 at 66Mhz
but---33Mhz ieee1394a ---- subsystem: Adaptec ???

xboom