Disk access/MPT under ESX3.5

[Daniel Ponticello]

Oh, btw, this make improvements only on 7.0-Release and Stable using ULE 
scheduler.
- Using 4BSD Scheduler will improve disk access speed but no cpu usage.
- On FreeBSD 6.2 and 6.3 this make no difference on cpu usage/speed 
(about 60mb/sec maximum using 100% cpu).


Thanks,

Daniel


Daniel Ponticello ha scritto:
>
> Much better:
>
> endevor# camcontrol negotiate 0:0 -W 16 -O 127 -R 40.000
> Current Parameters:
> (pass0:mpt0:0:0:0): sync parameter: 8
> (pass0:mpt0:0:0:0): frequency: 160.000MHz
> (pass0:mpt0:0:0:0): offset: 127
> (pass0:mpt0:0:0:0): bus width: 16 bits
> (pass0:mpt0:0:0:0): disconnection is enabled
> (pass0:mpt0:0:0:0): tagged queueing is enabled
> endevor# camcontrol inquiry da0
> pass0: <VMware Virtual disk 1.0> Fixed Direct Access SCSI-2 device
> pass0: 80.000MB/s transfers (40.000MHz, offset 127, 16bit), Command 
> Queueing Enabled
> endevor# 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 20.364577 secs (51490193 bytes/sec)
> endevor# 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 11.525560 secs (90978311 bytes/sec)
> endevor# 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 11.833996 secs (88607094 bytes/sec)
> endevor# 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 12.779979 secs (82048335 bytes/sec)
> endevor# 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 11.812926 secs (88765137 bytes/sec)
>
> Also CPU system load is lower: 40% instead of 70% on dual cpu, and 23% 
> instead of 50% on quad cpu.
>
> Still not as fast as debian, but really really usable now =)
>
> how i can make it mantain these settings at boot?
>
> Also, do you know why the first dd was slower?
>
> Thanks,
>
> Daniel
>
>
> Shunsuke SHINOMIYA ha scritto:
>>  Hello, Daniel
>>
>>  Can you execute camcontrol with some parameters again?
>>  For example, `camcontrol negotiate 0:0 -W 16 -O 127 -R 40.000'.
>>
>>   
>

-- 

WBR,
Cordiali Saluti,
 
Daniel Ponticello, VP of Engineering

Network Coordination Centre of Skytek

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