Team,

Any body knows why DB2 see only 71Mb memory free.
When I start db2 using db2start command. I can see the below entry in the db2diag.log. And I COULD NOT ABLE TO ACTIVATE DB with 1GB bufferpool.

DB2DIAG.log
=====================
Instance "db2inst1" uses "32" bits and DB2 code release "SQL08023"
with level identifier "03040106".
Informational tokens are "DB2 v8.1.3.96", "s050811", "MI00143", FixPak "10".
DATA #2 : System Info, 436 bytes
System: Linux Super88db 6 2 x86_64
CPU: total:4 online:4 Cores per socket:2 Threading degree per core:1
Physical Memory(MB): total:7974 free:71
Virtual Memory(MB): total:32543 free:24557
Swap Memory(MB): total:24569 free:24486
Kernel Params: msgMaxMessageSize:65536 msgMsgMap:131072 msgMaxQueueIDs:9000
msgNumberOfHeaders:131072 msgMaxQueueSize:131072
msgMaxSegmentSize:16 shmMax:2800000000 shmMin:1
shmIDs:4096
shmSegments:4096 semMap:32000 semIDs:128 semNum:32000
semUndo:32000 semNumPerID:250 semOps:2001 semUndoSize:20
semMaxVal:32767 semAdjustOnExit:32767

ACTIVATE COMMAND
===============================
Super88db: >db2 activate db Mandb1
SQL1478W The defined buffer pools could not be started. Instead, one small
buffer pool for each page size supported by DB2 has been started.
SQLSTATE=01626

FREE command and TOP command
==============================
Super88db: >free
total used free shared buffers cached
Mem: 8165012 539716 7625296 0 0 0
-/+ buffers/cache: 539716 7625296
Swap: 0 0 0

Super88db: >top
top - 13:08:48 up 6 days, 22:00, 2 users, load average: 0.00, 0.02, 0.00
Tasks: 64 total, 1 running, 63 sleeping, 0 stopped, 0 zombie
Cpu(s): 0.1%us, 0.1%sy, 0.0%ni, 99.8%id, 0.0%wa, 0.0%hi, 0.0%si, 0.0%st
Mem: 8165012k total, 539796k used, 7625216k free, 0k buffers
Swap: 0k total, 0k used, 0k free, 0k cached

PID USER PR NI VIRT RES SHR S %CPU %MEM TIME+ COMMAND
1 root 15 0 10348 688 580 S 0.0 0.0 0:00.58 init
3177 db2inst1 16 0 34740 7732 4464 S 0.0 0.1 0:00.02 db2bp
13750 db2inst1 15 0 10720 884 688 R 0.0 0.0 0:00.00 top
17425 root 15 0 5908 740 544 S 0.0 0.0 0:00.43 syslogd
17428 root 19 0 3800 432 344 S 0.0 0.0 0:00.00 klogd

Fyi.. This is VM environment..

Thanks
U

You are using 32 bit DB2. It can only use about 1.7 GB of memory total.

Andy

Here it is using/showing only 71mb. Why?
Even I updated the INSTANCE_MEMORY dbm cfg to 1GB.. Still no luck

-U

I think you have a basic mis-understanding of how memory works in Linux. A significant amount of memory is allocated to disk caching by Linux if not needed by something else, and is given back (made free) as soon as DB2 or anything else needs it.

You can use the top command and to see how much is used for disk cache by Linux.