DB2 8.2 UDF_MEM_SZ / ASL_HEAP_SZ

[Ralf Gross]

Hi,

the install guide of an application which will use our DB2 database
enumerate some DB2 parameters that have to be changed.

db2 => update dbm cfg using udf_mem_sz 6000

But this paramter does not exist in DB 8.2.

Version 8 incompatibilities with previous releases
<http://publib.boulder.ibm.com/infocenter/db2help/index.jsp?topic=/com.ibm.db2.udb.doc/admin/r0008109.htm>
* udf_mem_sz: UDFs no longer pass data in shared memory, so this parameter
is not supported

I found an old posting that mentioned the parameter ASL_HEAP_SZ as
alternative for udf_mem_sz. I'm not sure if I should use the same value
(6000) for ASL_HEAP_SZ that is mentioned in the install guide for
udf_mem_sz.

Ralf

[Knut Stolze]

Ralf Gross wrote:

Hi,

the install guide of an application which will use our DB2 database
enumerate some DB2 parameters that have to be changed.

db2 => update dbm cfg using udf_mem_sz 6000

But this paramter does not exist in DB 8.2.

Version 8 incompatibilities with previous releases
<http://publib.boulder.ibm.com/infocenter/db2help/index.jsp?topic=/com.ibm.db2.udb.doc/admin/r0008109.htm> * udf_mem_sz: UDFs no longer pass data in shared memory, so this parameter
is not supported

I found an old posting that mentioned the parameter ASL_HEAP_SZ as
alternative for udf_mem_sz. I'm not sure if I should use the same value
(6000) for ASL_HEAP_SZ that is mentioned in the install guide for
udf_mem_sz.

That's correct. UDF_MEM_SZ doesn't exist any longer (but you won't get an
error trying to set it - it will just be ignored). ASL_HEAP_SZ uses a
different unit to specify the amount of memory, and the memory utilization
is also different. So using the 6000 is not a good idea.

You might want to ask the application vendor what they recommend for DB2 V8
now. Or you just install the application and run it and handle
out-of-memory problems when they occur, i.e. just reactive.

--
Knut Stolze
DB2 Information Integration Development
IBM Germany

[Ralf Gross]

Knut Stolze wrote:

Ralf Gross wrote:

the install guide of an application which will use our DB2 database
enumerate some DB2 parameters that have to be changed.

db2 => update dbm cfg using udf_mem_sz 6000

But this paramter does not exist in DB 8.2.

Version 8 incompatibilities with previous releases

<http://publib.boulder.ibm.com/infocenter/db2help/index.jsp?topic=/com.ibm.db2.udb.doc/admin/r0008109.htm>

* udf_mem_sz: UDFs no longer pass data in shared memory, so this parameter
is not supported

I found an old posting that mentioned the parameter ASL_HEAP_SZ as
alternative for udf_mem_sz. I'm not sure if I should use the same value
(6000) for ASL_HEAP_SZ that is mentioned in the install guide for
udf_mem_sz.

That's correct. UDF_MEM_SZ doesn't exist any longer (but you won't get an
error trying to set it - it will just be ignored). ASL_HEAP_SZ uses a
different unit to specify the amount of memory, and the memory utilization
is also different. So using the 6000 is not a good idea.

You might want to ask the application vendor what they recommend for DB2 V8
now. Or you just install the application and run it and handle
out-of-memory problems when they occur, i.e. just reactive.

I asked them right after I noticed that UDF_MEM_SZ doesn't exist
anymore. They recommended to stay with the default paramter and keep in
mind to change this parameter if problems occure. It's somewhat funny
that db2 8.x is certified for this application...

Ralf