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uthaman · Beginner Joined: 09 Apr 2007 Posts: 14 Topics: 9

I am getting a 0C4 error when trying to write to a VSAM file. The error shows up as:

COMPLETION CODE - SYSTEM=04C USER=0000 REASON=00000000

Further down in the dump this message appears:

VOLUME COUNT FOR DD EXCEEDED: SPECIFIC- 4 NON-SPECIFIC- 113

The VSAM file is defined as:
DEFINE CL (NAME(VSAM1.ZERO.BAL1504.WORKFILE) -
CYL(5,5) -
KEYS(22 0) -
RECSZ(3026 3026) -
REUSE -
SPEED -
SHR(2,3)) -
DATA (NAME(VSAM1.ZERO.BAL1504.WORKFILE.DATA) -
CISZ(4096)) -
INDEX (NAME(VSAM1.ZERO.BAL1504.WORKFILE.INDEX) -
CISZ(2560))

The file generally has about 150,000 records in it, but we had a "perfect storm" last week and 400,000+ records flooded the file and blew it up.

Would increasing the CISZ fix this?

THANKS!!!

jsharon1248 · Posted: Wed Jun 04, 2008 2:39 pm Post subject:

A lot of this depends on how big the records really are. The RECSZ says the average is 3026, so that's what I'm using. With records at 3026, and the CI's at 4096, VSAM can only write 1 record per CI. Each track is a little less than 60,000 bytes. That means that you can write 14 CI's per track, each CI with 1 record, so 14 records per track. With 15 tracks per CYL you'll end up with 210 recs per CYL. So 5 CYLS? 1050 records in the primary. You're allocating for a bathtub toy boat and an aircraft carrier showed up. Using the values from your DEFINE, you need over 700 CYL to store your normal volume of 150,000 records. To accomodate the unexpected, you need about 2.5 times that so with the current CISZ, you'd want something with a healthy secondary allocation like CYL(725,125).

So let's see what happens if we play around with the CI size. At 3026, I'd want to use a CISZ that would be slightly higher than a multiple of that record size. Luckily, we don't have to look too far. 6144 will comfortably fit 2 records and leave less than 100 bytes unuseable. That's 1/10th the unuseable bytes that you had using 4096. So now, you'd fit 2 records per CI, but unfortunately, only 9 CI's per track. Still, you'd fit 18 records per track, and 270 records per CYL. Just doing the math, you'd need a little over 550 CYLS to store the same 150,000 records, about 20% less space. Now you could get away with an allocation using something like CYL(575,100).

Incidentally, your job terminated with an S04C, not an S0C4. S0C4 is something a little different.

jsharon1248 · Posted: Wed Jun 04, 2008 3:39 pm Post subject:

Actually, I was a little too generous with my track estimate being 'a little less than 60,000'. It's a little less than 56,000. So the 4096 CISZ becomes even worse because you'll only write 13 records per track and 195 per cylinder. Your 150,000 records would use about 780 CYL. The 6144 CISZ still writes 18 records per CI, so the 550 CYL looks even more attractive. You could also use 18432 as your CISZ to achieve the same 18 records per track. This might be a suitable option if the processing for your VSAM dataset is mostly sequential.