twa driver and 3ware 9690SA issues

[Josh Paetzel]

This is somewhat of a repost from questions@, and I'm currently  
engaged with 3ware about this issue.

I have several 3ware 9690SA SAS RAID controllers.   This item is very  
similar to their 9650SE controller.  It uses the same firmware and  
driver, the difference being it can handle SAS drives.  Up until this  
point all of the arrays we've used with these drives have been RAID 1  
arrays with 7200 RPM SATA drives, but recently we've started using  
15,000 MBA series Fujitsu SAS drives in places.

The arrays have always been detected as:

da0: <AMCC 9690SA-4I  DISK 4.06> Fixed Direct Access SCSI-5 device
da0: 100.000MB/s transfers

Which wasn't that much of an issue, as SATA drives aren't capable of  
sustained sequential 100 MB/sec transfers anyways, but the SAS drives  
we are getting are supposedly capable of 180 Megs/sec and I'm not  
seeing it.  I'm unsure of how to eliminate caching from the equation,  
simple tests like dd if=/dev/zero of=testfile bs=8m count=1000 seem to  
support what dmesg reports by returning 96 Meg/sec transfer rates

3ware has had me verify the savestor performance profile is set to  
performance, write-caching is enabled, and that I'm using the latest  
driver and firmware.

root at erlang / ->tw_cli /c0 show

Unit  UnitType  Status         %RCmpl  %V/I/M  Stripe  Size(GB)   
Cache  AVrfy
------------------------------------------------------------------------------
u0    RAID-1    OK             -       -       -       135.031    
ON     ON

VPort Status         Unit Size      Type  Phy Encl-Slot    Model
------------------------------------------------------------------------------
p0    OK             u0   136.98 GB SAS   0   -            FUJITSU  
MBA3147RC
p1    OK             u0   136.98 GB SAS   1   -            FUJITSU  
MBA3147RC

Name  OnlineState  BBUReady  Status    Volt     Temp     Hours   
LastCapTest
---------------------------------------------------------------------------
bbu   On           Yes       OK        OK       OK       0      xx-xxx- 
xxxx


At this point I'd be happy to somehow verify the 100 MB/sec reported  
by dmesg as either the real link speed, or as a bogus number.


This issue may have trickle down to 9650SE and 9550 series  
controllers, those also report 100 MB/sec links for me with SATA  
drives, and while that's well over the sequential capability of  
current SATA drives, it could be affecting cache transfer rates...not  
to mention RAID array configurations.

This test can't be considered at all conclusive, as I ran it on a  
production server:

root at markov / ->tw_cli /c0 show

Unit  UnitType  Status         %RCmpl  %V/I/M  Stripe  Size(GB)   
Cache  AVrfy
------------------------------------------------------------------------------
u0    RAID-10   OK             -       -       64K     596.025    
ON     OFF

Port   Status           Unit   Size        Blocks        Serial
---------------------------------------------------------------
p0     OK               u0     298.09 GB   625142448     WD-WCARW4254676
p1     OK               u0     298.09 GB   625142448     WD-WCARW3480367
p2     OK               u0     298.09 GB   625142448     WD-WCARW4254675
p3     OK               u0     298.09 GB   625142448     WD-WCARW3479101

root at markov / ->grep da0 /var/run/dmesg.boot
da0 at twa0 bus 0 target 0 lun 0
da0: <AMCC 9550SXU-4L DISK 3.08> Fixed Direct Access SCSI-5 device
da0: 100.000MB/s transfers
da0: 610330MB (1249955840 512 byte sectors: 255H 63S/T 77806C)
Trying to mount root from ufs:/dev/da0s1a
root at markov /home/jpaetzel ->dd if=/dev/zero of=test bs=8m count=100
100+0 records in
100+0 records out
838860800 bytes transferred in 6.923690 secs (121158052 bytes/sec)

Kind of what I expect, and faster than 100 Megs/sec

Thanks,

Josh Paetzel