Question on Read-Write Error Recovery mode page PER operation

Mark Evans Mark.Evans at wdc.com
Mon Nov 10 07:53:59 PST 2008


Formatted message: <a href="r0811100_f.htm">HTML-formatted message</a>

Hello,
I will check this and make corrections as I make a new revision of SBC-3.
Please check the next revision of SBC-3 to insure that your issues have been
addressed.
Please feel free to call or send an email to me if you have any additional
questions about this stuff. 
Regards, 
Mark Evans 
Western Digital Corporation 
5863 Rue Ferrari 
San Jose,  CA  95138 
Email: mark.evans at wdc.com 
Office: 408.363.5257 
Fax: 408.363.5139 
Cell: 408.391.7805 
________________________________
From: owner-t10 at t10.org [mailto:owner-t10 at t10.org] On Behalf Of Knight,
Frederick
Sent: Sunday, November 09, 2008 5:05 PM
To: Bill.Martin at emulex.com; t10 at t10.org
Cc: Narayan.Ayalasomayajula at emulex.com
Subject: RE: Question on Read-Write Error Recovery mode page PER operation 
Well, SBC-2 and SBC3r11 have the NOT.  07-447r1 is the one that changed it
|from this older text:
A post error (PER) bit set to one specifies that the device server shall
report recovered errors. A PER bit set to
zero specifies that the device server shall not report recovered errors, and
the device server shall perform
error recovery procedures within the limits established by the error
recovery parameters.
    Fred Knight
________________________________
From: Bill.Martin at Emulex.Com [mailto:Bill.Martin at Emulex.Com] 
Sent: Friday, November 07, 2008 6:43 PM
To: t10 at t10.org
Cc: Narayan.Ayalasomayajula at Emulex.Com
Subject: Question on Read-Write Error Recovery mode page PER operation 
In the description of PER in the Read-Write Error Recovery mode page, the
following is stated:
A post error (PER) bit set to one specifies that if a recovered read error
occurs during a command performing a read or write operation, then the
device server shall terminate the command with CHECK CONDITION status with
the sense key set to RECOVERED ERROR. A PER bit set to zero specifies that
if a recovered read error occurs during a command performing a read or write
operation, then the device server shall terminate the command with CHECK
CONDITION status, and shall perform error recovery procedures within the
limits established by the error recovery parameters. If the DTE bit is set
to one, then the PER bit shall be set to one.
It seems that the first and second sentences require mostly the same thing
as far as reporting a CHECK CONNDITION.  I think that the second sentence is
missing a "not" in the device server shall NOT terminate the command with
CHECK CONDITION status, ...
This interpretation is consistent with the first two rows of table 128 also,
which state "The device server shall not report recovered read errors. The
device server shall terminate a command performing a read or write operation
with CHECK CONDITION status before the transfer count is exhausted only if
an unrecovered error is detected."
Bill Martin
Emulex
Office of Technology
Industry Standards
916 772-3658
916 765-6875 (Cell)
bill.martin at emulex.com



More information about the T10 mailing list