Commands Queued Output

[Randall Smith]

Thanks Patrick.

I started a log using cron to capture the state of proc/scsi/aic7xxx/0 
daily.  I found that the "commands queued" number is jumping during the 
tape backup, which tars the root directory.  Does that give you some 
idea of what is happening?  And how can I set the commands queued back 
to zero to prevent a crash?

Randall

Patrick_Boyd at Dell.com wrote:
> 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)
> 
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