Max # of threads - Need Direction

Hi,

Is there a documentaion on how to minitir the the max # of threads setting
with Ananlysis Server?

We are testing the cube building process on a 64 bit machine with 8
processors. The Max # of threads is set to 16 (default).

When we run 4 partitions in parllel, Analysis services allmost takes 4 times
more than what ot is taking to process the one partition at a time. Not sure
if it is processing them in parllel internally.

We ran these 4 queires directly on the DB2 machine and they are all done in
5 minutes. Where as the log file shows they are taking 25 to 30 minutes when
we build 4 partitons in parllel.

Just wondering if this has to do anything with the Mx # of threads setting
on the Analysis Server.

Any direction in this regard is appreciated.

Thanks,

Sam.

So the queries take 20 to 30 min when run at the same time? You have run
these queies outside of AS in parallel?

The Max number of threads really isn't going to do much here, you could see
if the number of Context Switches is really high when processing by going to
Performance Monitor and looking in System:Context Switches.

Then main properties to look at are the Process Buffer size and the read
ahead buffer. If they are set too high it could prevent the parallel
processing for working as it should, or if to low it will cause AS to write
to disk much too often.

David

"Prasad" <Prasad (AT) discussions (DOT) microsoft.com> wrote

Hi,

Is there a documentaion on how to minitir the the max # of threads setting
with Ananlysis Server?

We are testing the cube building process on a 64 bit machine with 8
processors. The Max # of threads is set to 16 (default).

When we run 4 partitions in parllel, Analysis services allmost takes 4
times
more than what ot is taking to process the one partition at a time. Not
sure
if it is processing them in parllel internally.

We ran these 4 queires directly on the DB2 machine and they are all done
in
5 minutes. Where as the log file shows they are taking 25 to 30 minutes
when
we build 4 partitons in parllel.

Just wondering if this has to do anything with the Mx # of threads setting
on the Analysis Server.

Any direction in this regard is appreciated.

Thanks,

Sam.

Thanks for the reply.

Yes we ran these 4 queries in parallel on the DB2 machine stting the output
to Null. It look only 5 minutes.

Driver: IBM DB2 ODBC Driver
version: 8.01.06.744
File: DB2CLIO.DLL
Date: 01/06/2005.

We have 64 GB of memory on this machine. 8 CPU's. I am going to bring down
the Read - a - head buffer and try again. I will watch the context switches
as well.

Can you please confirm if we are using the optimal driver? And any ideas in
improving the perfromance.

"Prasad" wrote:

Hi,

Is there a documentaion on how to minitir the the max # of threads setting
with Ananlysis Server?

We are testing the cube building process on a 64 bit machine with 8
processors. The Max # of threads is set to 16 (default).

When we run 4 partitions in parllel, Analysis services allmost takes 4 times
more than what ot is taking to process the one partition at a time. Not sure
if it is processing them in parllel internally.

We ran these 4 queires directly on the DB2 machine and they are all done in
5 minutes. Where as the log file shows they are taking 25 to 30 minutes when
we build 4 partitons in parllel.

Just wondering if this has to do anything with the Mx # of threads setting
on the Analysis Server.

Any direction in this regard is appreciated.

Thanks,

Sam.