Extremely slow write speeds to disk : FreeBSD 7.1 and Dell SAS 6/iR Adapter

O. Hartmann ohartman at zedat.fu-berlin.de
Thu Feb 12 07:18:09 PST 2009

Bradley Radjoo wrote:
> Thanks very much Richard,
> (They are 2 X 73Gig Ultra 320 scsi SAS drives)
> BUT seems that even with the UP kernel, I still get issues..
> This is what I see in dmesg :
> mpt0: <LSILogic SAS/SATA Adapter> port 0xec00-0xecff mem
> 0xdfcec000-0xdfceffff,0xdfcf0000-0xdfcfffff irq 15 at device 0.0 on pci5
> mpt0: [ITHREAD]
> mpt0: MPI Version=
> mpt0: mpt_wait_req(6) timed out
> mpt0: port 0 enable timed out
> mpt0: failed to enable port 0
> mpt0: unable to initialize IOC
> da0 at mpt0 bus 0 target 0 lun 0
> ses0 at mpt0 bus 0 target 8 lun 0
> Please can you assist and advise 
> -----Original Message-----
> From: Richard Tector [mailto:richardtector at thekeelecentre.com] 
> Sent: 12 February 2009 01:57 PM
> To: Bradley Radjoo
> Cc: freebsd-performance at freebsd.org
> Subject: Re: Extremely slow write speeds to disk : FreeBSD 7.1 and Dell
> SAS 6/iR Adapter
> Bradley Radjoo wrote:
>> Greetings,
>> Please can you assist.
>> I have attempted most of the popular BSD Variants such as NetBSD, Open
>> BSD, FreeBSD...
>> The only distrubution that seems to work on the is Dell SAS 6/iR
> Adapter
>> is FreeBSD 7.1
>> Firmware version & date : 9/29/2008
>> But the issue is that writing to disk is extremely slow...i.e. 14Mb
> per
>> second....
>> If I install any other linux distribution, like CentOS, write speek is
>> the way it should be..it averages around 190Mb+ per second
>> I was hoping if it were at all possible for you to assist me in with a
>> later RAID Controller Driver for the SAS 6/iR Adapter
> Try:
> hw.mpt.enable_sata_wc=1
> in /boot/loader.conf and reboot.
> Assuming you are using SATA drives, the write cache is disabled by 
> default. This reenables it. The mpt manpage holds more information.
> Regards,
> Richard
> Please note: This email and its content are subject to the disclaimer as displayed at the following link http://www.is.co.za/legal/E-mail+Confidentiality+Notice+and+Disclaimer.htm. Should you not have Web access, send a mail to disclaimers at is.co.za and a copy will be emailed to you.
> _______________________________________________
> freebsd-performance at freebsd.org mailing list
> http://lists.freebsd.org/mailman/listinfo/freebsd-performance
> To unsubscribe, send any mail to "freebsd-performance-unsubscribe at freebsd.org"

We're using a Dell 1950-III Poweredge server with two XEON 4-Core-CPUs 
and at the momen one 750GB SATA drive.
This box suffers from incredible slow drive access speeds - 
approximately a half of what I see on other boxes around.

When I read this posting I was quite happy having found a possible 
solution, but I can't find the above mentioned OID, FreeBSD 
8.0-CURRENT/amd64 (running on this box) shows only "hw.ata.wc: 1" as
a relevant OID. No hw.mpt.XXX OIDs anywere. This is the part from DMESG 
reflecting MPT:

mpt0: <LSILogic SAS/SATA Adapter> port 0xec00-0xecff mem 
0xfc4fc000-0xfc4fffff,0xfc4e0000-0xfc4effff irq 16 at device 0.0 on pci1
mpt0: [ITHREAD]
mpt0: MPI Version=
mpt0: Capabilities: ( RAID-0 RAID-1E RAID-1 )
mpt0: 0 Active Volumes (2 Max)
mpt0: 0 Hidden Drive Members (14 Max)

I can not tell you, at this very moment, what configuration has been 
done in the BIOS. The SATA HD is recognized as da0:

da0 at mpt0 bus 0 target 0 lun 0
da0: <ATA Hitachi HUA72107 A74A> Fixed Direct Access SCSI-5 device
da0: 300.000MB/s transfers
da0: Command Queueing Enabled
da0: 715404MB (1465149168 512 byte sectors: 255H 63S/T 91201C)

Maybe someon can followup on this if there is some kind of issue ...

Thanks in advance,

More information about the freebsd-performance mailing list