Linux on PE2950, PV220S and very slow PV124T

David B. haazeloud at gmail.com
Fri Aug 22 07:41:23 CDT 2008 

Hi,

I've got I/O performance problem during quite some time (several 
mounths) without any solutions for now.
Especially while writing a LTO3 Tape.

OS : CentOS 5 64bits

Hardware :
PE 2950
Intel Xeon 5120
RAM : 1 GB
PERC 5/i Integrated (with 6 x 7200rpm SATA HDDs, 2 x RAID 5 arrays (3 
disks per array).
39320A Ultra320 with external PV124T (LTO3 tape drive)
PERC 4/DC with external PV220S (14 x 300 Go SCSI 10000rpm, 2 x RAID 5 
arrays (7 disks per array).

Tape write and read are very slow.
This was a bit better a mounth ago, since a power outage, system seems 
to be slow, but I can't figure out why !

Tape write :
Quite simple, reading files from PV220S to LTO3 Tape.
For a 300 GB of data transfert (lots of files, around 12M), it take 
around 20 hours !

Backup to tape through tar :
mt -f /dev/st0 setblk 0
tar -b 128 -cvf /dev/st0 /my_backup_dir

No load on OS during transfert, just tar process !
No patrol read operation during process.

Omreport seems not to report any problem :
 > omreport chassis
Health

Main System Chassis

SEVERITY : COMPONENT
Ok       : Fans
Ok       : Intrusion
Ok       : Memory
Ok       : Power Supplies
Ok       : Processors
Ok       : Temperatures
Ok       : Voltages
Ok       : Hardware Log
Ok       : Batteries

 > omreport storage controller
List of Controllers in the system

Controllers
ID                                : 0
Status                            : Ok
Name                              : PERC 4/DC
Slot ID                           : PCI Slot 2
State                             : Ready
Firmware Version                  : 352D
Minimum Required Firmware Version : Not Applicable
Driver Version                    : Not Applicable
Minimum Required Driver Version   : Not Applicable
Number of Connectors              : 2
Rebuild Rate                      : 30%
BGI Rate                          : Not Applicable
Check Consistency Rate            : Not Applicable
Reconstruct Rate                  : Not Applicable
Alarm State                       : Enabled
Cluster Mode                      : Not Applicable
SCSI Initiator ID                 : 7
Cache Memory Size                 : 128 MB
Patrol Read Mode                  : Auto
Patrol Read State                 : Stopped
Patrol Read Rate                  : Not Applicable
Patrol Read Iterations            : 161

ID                                : 1
Status                            : Ok
Name                              : SCSI Card 39320A Ultra320 SCSI
Slot ID                           : PCI Slot 3
State                             : Ready
Firmware Version                  : Not Applicable
Minimum Required Firmware Version : Not Applicable
Driver Version                    : Not Applicable
Minimum Required Driver Version   : Not Applicable
Number of Connectors              : 2
Rebuild Rate                      : Not Applicable
BGI Rate                          : Not Applicable
Check Consistency Rate            : Not Applicable
Reconstruct Rate                  : Not Applicable
Alarm State                       : Not Applicable
Cluster Mode                      : Not Applicable
SCSI Initiator ID                 : Not Applicable
Cache Memory Size                 : Not Applicable
Patrol Read Mode                  : Not Applicable
Patrol Read State                 : Not Applicable
Patrol Read Rate                  : Not Applicable
Patrol Read Iterations            : Not Applicable

ID                                : 2
Status                            : Ok
Name                              : PERC 5/i Integrated
Slot ID                           : Embedded
State                             : Ready
Firmware Version                  : 5.2.1-0067
Minimum Required Firmware Version : Not Applicable
Driver Version                    : 00.00.03.15-RH1
Minimum Required Driver Version   : Not Applicable
Number of Connectors              : 2
Rebuild Rate                      : 30%
BGI Rate                          : 30%
Check Consistency Rate            : 30%
Reconstruct Rate                  : 30%
Alarm State                       : Not Applicable
Cluster Mode                      : Not Applicable
SCSI Initiator ID                 : Not Applicable
Cache Memory Size                 : 256 MB
Patrol Read Mode                  : Auto
Patrol Read State                 : Stopped
Patrol Read Rate                  : 30%
Patrol Read Iterations            : 54

FW seems to be uptodate.

I/O read on PV220S, seems to be not too bad :
dd if=/dev/zero of=testfile bs=1M count=2000 && sync
2000+0 records in
2000+0 records out
2097152000 bytes (2.1 GB) copied, 27.4402 seconds, 76.4 MB/s

SCSI chain between 39320A and PV124T looks good :
cat /proc/scsi/aic79xx/1
Adaptec AIC79xx driver version: 3.0
Adaptec 39320A Ultra320 SCSI adapter
aic7902: Ultra320 Wide Channel A, SCSI Id=7, PCI-X 101-133Mhz, 512 SCBs
Allocated SCBs: 4, SG List Length: 128

Serial EEPROM:
0x17c8 0x17c8 0x17c8 0x17c8 0x17c8 0x17c8 0x17c8 0x17c8
0x17c8 0x17c8 0x17c8 0x17c8 0x17c8 0x17c8 0x17c8 0x17c8
0x09f4 0x0142 0x2807 0x0010 0xffff 0xffff 0xffff 0xffff
0xffff 0xffff 0xffff 0xffff 0xffff 0xffff 0x0430 0xb3f3

Target 0 Negotiation Settings
         User: 320.000MB/s transfers (160.000MHz RDSTRM|DT|IU|RTI|QAS, 
16bit)
Target 1 Negotiation Settings
         User: 320.000MB/s transfers (160.000MHz RDSTRM|DT|IU|RTI|QAS, 
16bit)
Target 2 Negotiation Settings
         User: 320.000MB/s transfers (160.000MHz RDSTRM|DT|IU|RTI|QAS, 
16bit)
Target 3 Negotiation Settings
         User: 320.000MB/s transfers (160.000MHz RDSTRM|DT|IU|RTI|QAS, 
16bit)
Target 4 Negotiation Settings
         User: 320.000MB/s transfers (160.000MHz RDSTRM|DT|IU|RTI|QAS, 
16bit)
Target 5 Negotiation Settings
         User: 320.000MB/s transfers (160.000MHz RDSTRM|DT|IU|RTI|QAS, 
16bit)
Target 6 Negotiation Settings
         User: 320.000MB/s transfers (160.000MHz RDSTRM|DT|IU|RTI|QAS, 
16bit)
         Goal: 160.000MB/s transfers (80.000MHz DT, 16bit)
         Curr: 160.000MB/s transfers (80.000MHz DT, 16bit)
         Channel A Target 6 Lun 0 Settings
                 Commands Queued 7192757
                 Commands Active 0
                 Command Openings 1
                 Max Tagged Openings 0
                 Device Queue Frozen Count 0
         Channel A Target 6 Lun 1 Settings
                 Commands Queued 60
                 Commands Active 0
                 Command Openings 1
                 Max Tagged Openings 0
                 Device Queue Frozen Count 0
Target 7 Negotiation Settings
         User: 320.000MB/s transfers (160.000MHz RDSTRM|DT|IU|RTI|QAS, 
16bit)
Target 8 Negotiation Settings
         User: 320.000MB/s transfers (160.000MHz RDSTRM|DT|IU|RTI|QAS, 
16bit)
Target 9 Negotiation Settings
         User: 320.000MB/s transfers (160.000MHz RDSTRM|DT|IU|RTI|QAS, 
16bit)
Target 10 Negotiation Settings
         User: 320.000MB/s transfers (160.000MHz RDSTRM|DT|IU|RTI|QAS, 
16bit)
Target 11 Negotiation Settings
         User: 320.000MB/s transfers (160.000MHz RDSTRM|DT|IU|RTI|QAS, 
16bit)
Target 12 Negotiation Settings
         User: 320.000MB/s transfers (160.000MHz RDSTRM|DT|IU|RTI|QAS, 
16bit)
Target 13 Negotiation Settings
         User: 320.000MB/s transfers (160.000MHz RDSTRM|DT|IU|RTI|QAS, 
16bit)
Target 14 Negotiation Settings
         User: 320.000MB/s transfers (160.000MHz RDSTRM|DT|IU|RTI|QAS, 
16bit)
Target 15 Negotiation Settings
         User: 320.000MB/s transfers (160.000MHz RDSTRM|DT|IU|RTI|QAS, 
16bit)

  I've tried deadline and CFQ for IO scheduler, quite the same thing...

  LTO Tape drive : Compression enable

  I've found this that i haven't tried yet...
  http://lists.us.dell.com/pipermail/linux-poweredge/2007-March/029916.html

  Did someone have some idea ?

  Thank you.
  David

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