Re: Intermittent allocation issue

[Dave Schnee <DSchnee@xxxxxxxxxxxxxxxxxxx>]

Brad:

I had this kind of problem several times over the last few months.  There 
were 2 separate reasons, neither of them due to any out-and-out logic 
problem.

First, if you are using high-availability software, there can be a 
condition where you clear a member (or add one) and then write to it where 
your HA software grabs enough of a lock on the member and/or file to 
prevent you from doing what you want.  This one bit me when populating a 
source file member that I had just added (probably not your specific 
problem).  Your *EXCL lock on the *FILE may not give you enough control 
over both the MEMBER and the data space in it.

Second (and more insidious) is the use of Save-While-Active.  If you have 
some kind of SAVOBJ or SAVLIB going, there are internal seize-like locks 
obtained on some objects that have nothing to do with your lock but CAN 
prevent you from updating something.  In my case, it was updating a 
*DTAARA on which I had an *EXCLRD lock that failed.  The workaround here 
was to monitor for the failure, delay a short interval and retry.

The system is getting more and more interesting.

Dave Schnee,
Barsa Consulting Group, LLC

---------------     Brad Porter wrote:     ---------------

date: Tue, 13 Dec 2005 14:15:24 -0700
from: "Brad Porter" <bradp@xxxxxxxxxxxx>
subject: Intermittent allocation issue

I am having a problem with a file allocation but it is very intermittent.
I allocate a file, copy records from the file, clear the file and then 
copy
back.  Some times the clear operation fails with a cannot allocate error.
Here is a copy of the code and the error message.

0016.00
0017.00              ALCOBJ     OBJ((GPPTRPM *FILE *EXCL)) WAIT(600)
0018.00              MONMSG     MSGID(CPF1002) EXEC(DO)
0019.00              SNDPGMMSG  MSG('Can not Allocate object GPPTRPM 
File.')
0020.00              GOTO END
0021.00              ENDDO
0022.00
0023.00              DLTF       FILE(QTEMP/GPPTRPMBK)
0024.00              MONMSG     MSGID(CPF0000)
0025.00
0026.00              CPYF       FROMFILE(GPPTRPM) TOFILE(QTEMP/GPPTRPMBK) 
+
0027.00                           MBROPT(*REPLACE) CRTFILE(*YES) +
0028.00                           INCREL((*IF PMSTAT *EQ 'A'))
0029.00
0030.00              CLRPFM     FILE(GPPTRPM)
0031.00
0031.00
0032.00              CPYF       FROMFILE(QTEMP/GPPTRPMBK) TOFILE(GPPTRPM) 
+
0033.00                           MBROPT(*ADD)
0034.00
0035.00              DLCOBJ     OBJ((GPPTRPM *FILE *EXCL))
0036.00 END:
0037.00              ENDPGM

Message . . . . :   CPF3130 received by GP5903CP at 3000. (C D I R)
 Cause . . . . . :   Control language (CL) program GP5903CP in library
GP#LIBR
   detected an error at statement number 3000. Message text for CPF3130 
is:
   Member GPPTRPM already in use.