Commands Queued Output

[Patrick_Boyd at Dell.com]

Target 6 should be the enclosure or backplane. As far as why the
commands are being queued to it, it might just be that something is
trying to send SCSI pass throughs or IO that the enclosure doesn't
understand.

Patrick Boyd
Dell Storage Software Engineer
(512)728-3182
 

-----Original Message-----
From: linux-poweredge-bounces at dell.com
[mailto:linux-poweredge-bounces at dell.com] On Behalf Of Randall Smith
Sent: Thursday, September 21, 2006 12:06 PM
To: linux-poweredge-Lists
Subject: Commands Queued Output

Sorry if this dups.  I didn't send in my confirmation in time, so the
first attempt got rejected.

The following is a message I sent a while back to a list that no longer
exists.  The server discussed here crashed this morning with a kernel
panic and after a reboot the commands queued on Target 6 stands at 2.
The machine is a PowerEdge 2500 running Debian Sarge.  I don't know for
sure this is what caused the crash, but I'd like to understand it
regardless.  Any insight into what the Target 6 information means and
why it has a huge queue would be greatly appreciated.

Thanks.  -Randall

cat /proc/scsi/aic7xxx/0

is producing this output

---snip---
Target 5 Negotiation Settings
         User: 160.000MB/s transfers (80.000MHz DT, offset 127, 16bit)
Target 6 Negotiation Settings
         User: 160.000MB/s transfers (80.000MHz DT, offset 127, 16bit)
         Goal: 80.000MB/s transfers (40.000MHz, offset 32, 16bit)
         Curr: 80.000MB/s transfers (40.000MHz, offset 32, 16bit)
         Channel A Target 6 Lun 0 Settings
                 Commands Queued 26151289
                 Commands Active 0
                 Command Openings 1
                 Max Tagged Openings 0
                 Device Queue Frozen Count 0
---snip---

and I'm concerned because I don't know what it means.  I have a two disk
mirrored array setup.  I don't know what Target 6 is and why it has
commands queued or even what that means.  I'm guessing it isn't a good
thing.  Any help is appreciated.

--Randall

output of afacli:

AFA0> container list
Executing: container list
Num          Total  Oth Chunk          Scsi   Partition
Label Type   Size   Ctr Size   Usage   B:ID:L Offset:Size
----- ------ ------ --- ------ ------- ------ -------------
  0    Mirror 33.8GB            Valid   0:00:0 64.0KB:33.8GB
  /dev/sda             MIRROR_DWS       0:01:0 64.0KB:33.8GB

AFA0> disk list
Executing: disk list

B:ID:L  Device Type     Blocks    Bytes/Block Usage            Shared
Rate
------  --------------  --------- ----------- ---------------- ------
----
0:00:0   Disk            71132959  512         Initialized      NO
160
0:01:0   Disk            71132959  512         Initialized      NO
160

AFA0> disk show smart /all
Executing: disk show smart /all=TRUE

         Smart    Method of         Enable
         Capable  Informational     Exception  Performance  Error
B:ID:L  Device   Exceptions(MRIE)  Control    Enabled      Count
------  -------  ----------------  ---------  -----------  ------
0:00:0     Y            6             Y           N             0
0:01:0     Y            6             Y           N             0

AFA0> disk show defects 0
Executing: disk show defects (ID=0)

Number of PRIMARY defects on drive: 978

Number of GROWN defects on drive: 0

AFA0> disk show defects 1
Executing: disk show defects (ID=1)

Number of PRIMARY defects on drive: 112

Number of GROWN defects on drive: 0


result of lspci is

0000:01:02.1 RAID bus controller: Dell PowerEdge Expandable RAID
Controller 3/Di (rev 01) 0000:02:04.0 SCSI storage controller: Adaptec
RAID subsystem HBA (rev 01)
0000:02:04.1 SCSI storage controller: Adaptec AIC-7899P U160/m (rev 01)
0000:03:06.0 SCSI storage controller: Adaptec AHA-3960D / AIC-7899A
U160/m (rev 01)
0000:03:06.1 SCSI storage controller: Adaptec AHA-3960D / AIC-7899A
U160/m (rev 01)

_______________________________________________
Linux-PowerEdge mailing list
Linux-PowerEdge at dell.com
http://lists.us.dell.com/mailman/listinfo/linux-poweredge
Please read the FAQ at http://lists.us.dell.com/faq