By those four BUFFERPOOL settings, you're allowing all of them to grow, to a combined maximum size of 30GB, with (initial) V segment already consuming 2GB. If all bufferpools grew to their configured maximum (they currently add up to 29.6044 GB, plus some R and M memory), there'd be nothing left for additional virtual (V) memory. New V segments often get allocated (even with seemingly sufficient free blocks in existing V segments) when a larger contiguous block of memory is needed (in your backup case: some 600kB).
So, assuming you really need all four bufferpools (i.e. you have dbspaces utilizing the respective page sizes), you still shouldn't allow them to grow so big, or you'd switch to static configuration altogether. A bufferpool cannot shrink, afaik, nor get deallocated.
Andreas
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Andreas Legner
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Original Message:
Sent: Tue April 18, 2023 03:06 PM
From: Hugo Tellez
Subject: SHMTOTAL maxed on Workgroup Edition
Hi,
I am running 14.10.FC7W1WE on Linux 64-bit VM.
The SHMTOTAL has reached the license restriction of 32G and now Onbar Level 0 backups will not run because onbar cannot grab enough memory.
13:20:26 Warning: The IBM IDS Workgroup Edition license restriction limits
13:20:26 the total shared memory size for this server to 33554432 KB.
13:20:26 Size of resident + virtual segments 413696 KB + 34189312 KB > 33554432 KB.
13:20:26 Size of resident + virtual segments 413696KB + 34189312KB > 33554432KB
13:20:26 total allowed by configuration parameter SHMTOTAL
13:20:26 CDR 625001 byte memory allocation failed (Pool:arc_800992 Thread:ontape).
13:20:26 Assert Warning: ISAM error: An error has occurred during archive back up.
Memory segments are as follows:
Segment Summary:
id key addr size ovhd class blkused blkfree
65539 525d4801 44000000 423624704 5405944 R* 103310 114
65540 525d4802 5d400000 2147483648 25167624 V* 459065 65223
65541 525d4803 dd400000 6610223104 1 B* 1613824 0
65542 525d4804 267400000 2692743168 1 B* 657408 0
65543 525d4805 307c00000 2671771648 1 B* 652288 0
65544 525d4806 3a7000000 12926844928 1 B* 3155968 0
65545 525d4807 6a9800000 561152 7848 M 137 0
65546 525d4808 6a9889000 561152 7848 M 135 2
65547 525d4809 6a9a00000 201326592 1 B* 49152 0
65548 525d480a 6b5a00000 201326592 1 B* 49152 0
65549 525d480b 6c1a00000 67108864 1 B* 16384 0
65550 525d480c 6c5a00000 201326592 1 B* 49152 0
65551 525d480d 6d1a00000 67108864 1 B* 16384 0
65552 525d480e 6d5a00000 402653184 1 B* 98304 0
65553 525d480f 6eda00000 402653184 1 B* 98304 0
65554 525d4810 705a00000 402653184 1 B* 98304 0
65555 525d4811 71da00000 402653184 1 B* 98304 0
65556 525d4812 735a00000 402653184 1 B* 98304 0
65557 525d4813 74da00000 402653184 1 B* 98304 0
65558 525d4814 765a00000 402653184 1 B* 98304 0
65559 525d4815 77da00000 805306368 1 B* 196608 0
65560 525d4816 7ada00000 805306368 1 B* 196608 0
65561 525d4817 7dda00000 805306368 1 B* 196608 0
65562 525d4818 80da00000 805306368 1 B* 196608 0
65563 525d4819 83da00000 67108864 1 B* 16384 0
65564 525d481a 841a00000 40820736 1 B* 9966 0
Total: - - 34359738368 - - 8323269 65339
I have tried onmode -F but this will not release Bufferpool segments.
I have tried onmode -B reset and while all buffer cache is cleared it still does not allow onbar backup to run.
IBM Support has only suggested to reduce the buffer pool settings and restart the instance.
Is there a way to reduce the buffer pool settings to reduce the SHMTOTAL so that a full backup can run?
Buffer pools are set as follows:
BUFFERPOOL size=2K,start_memory=6gb,memory=8gb
BUFFERPOOL size=4K,start_memory=2500mb,memory=3gb
BUFFERPOOL size=8K,start_memory=2500mb,memory=3gb
BUFFERPOOL size=16K,start_memory=12gb,memory=16gb
Thanks,
Hugo
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Hugo Tellez
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