Gregor Kovač wrote:
Knut Stolze wrote:
>Gregor Kovač wrote:
>>Hi!
Is it possible to alter tablespace so that you don't connect to the
database?
The problem I have is this. I got a DB backup from a machine with 16 Gb
of RAM. There was a bufferpool set to use 10 Gb of RAM. Now I have to put
it on a machine with only 8 Gb of RAM. The restore is OK, but I'd like to
decrease that bufferpool to only use 4 Gb.
You want to change the tablespace or the bufferpool?
You could simply start DB2 and activate the database. If there is not
sufficient RAM, DB2 will start with very small bufferpools (usually
hidden). Now you can change the BP and re-activate the database with the
new, reduced size.
We are on a 64-bit machine and Windows and when you connect to the database
the pagefile (Windows virtual memory) grows for Gbs and it takes almost an
hour for connect to succeed.
I just thought that there is a command like activate database with default
bufferpool :)))
I pinged backstage and here is the recommendation:
DB2_OVERRIDE_BPF
Operating system: All
Default: not set, Values: a positive numeric number of pages OR
<entry>[;<entry>…] where <entry>=<buffer pool ID>,<number of pages>
This variable specifies the size of the buffer pool, in pages, to be
created at database activation, rollforward recovery, or crash recovery.
It is useful when memory constraints cause failures to occur during
database activation, rollforward recovery, or crash recovery. The memory
constraint could arise either in the rare case of a real memory shortage
or, because of the attempt by the database manager to allocate a large
buffer pool, in the case where there were inaccurately configured buffer
pools. For example, when even a minimal buffer pool of 16 pages is not
brought up by the database manager, try specifying a smaller number of
pages using this environment variable. The value given to this variable
overrides the current buffer pool size.
You can also use <entry>[;<entry>…] where <entry>=<buffer pool
ID>,<number of pagesto temporarily change the size of all or a subset
of the buffer pools so that they can start up.
--
Serge Rielau
DB2 Solutions Development
IBM Toronto Lab
