Disk access/MPT under ESX3.5

[Daniel Ponticello]

Hello,


monitor# camcontrol negotiate 0:0 -W 16
Current Parameters:
(pass0:mpt0:0:0:0): sync parameter: 0
(pass0:mpt0:0:0:0): offset: 0
(pass0:mpt0:0:0:0): bus width: 8 bits
(pass0:mpt0:0:0:0): disconnection is enabled
(pass0:mpt0:0:0:0): tagged queueing is enabled
monitor# dd if=/dev/zero of=/var/tmp/dead.file bs=1024k count=1000
1000+0 records in
1000+0 records out
1048576000 bytes transferred in 32.421679 secs (32341817 bytes/sec)
monitor# dd if=/dev/zero of=/var/tmp/dead.file bs=1024k count=1000
1000+0 records in
1000+0 records out
1048576000 bytes transferred in 20.355797 secs (51512402 bytes/sec)

No improvements. But it looks like it did not renegotiated the transfers 
data rate that for
some odd reasons are setted as 3.3MB/S instead of 320mb/s.

I made some tests using linux 2.18 (debian):

debiantest:/home/daniel# uname -a
Linux debiantest 2.6.18-6-686 #1 SMP Sun Feb 10 22:11:31 UTC 2008 i686 
GNU/Linux

scsi0 : ioc0: LSI53C1030, FwRev=00000000h, Ports=1, MaxQ=128, IRQ=169
  Vendor: VMware    Model: Virtual disk      Rev: 1.0
  Type:   Direct-Access                      ANSI SCSI revision: 02
 target0:0:0: Beginning Domain Validation
 target0:0:0: Domain Validation skipping write tests
 target0:0:0: Ending Domain Validation
 target0:0:0: FAST-160 WIDE SCSI 320.0 MB/s DT IU RDSTRM RTI WRFLOW 
PCOMP (6.25
ns, offset 127)

debiantest:/home/daniel# dd if=/dev/zero of=dead.file bs=1024k count=1000
1000+0 records in
1000+0 records out
1048576000 bytes (1.0 GB) copied, 5.01316 seconds, 209 MB/s


=(


Shunsuke SHINOMIYA ha scritto:
>> da0 at mpt0 bus 0 target 0 lun 0
>> da0: <VMware Virtual disk 1.0> Fixed Direct Access SCSI-2 device
>> da0: 3.300MB/s transfers
>> da0: Command Queueing Enabled
>> da0: 34816MB (71303168 512 byte sectors: 255H 63S/T 4438C)
>>     
>
>  Can you re-negotiate transfer rate, using camcontrol?
>  `camcontrol negotiate 0:0 -W 16' might improve that transfer settings.
>  
>  camcontrol needs passthrough device support in a kernel.
>
>
>   

-- 

WBR,
Cordiali Saluti,
 
Daniel Ponticello, VP of Engineering

Network Coordination Centre of Skytek

---
- For further information about our services: 
- Please visit our website at http://www.Skytek.it
---