contention on dstpool

Hi, I run 'onstat -g spi | sort -nr -k 2 |head -20 , and the output show high contention on dstpool,currently the ds_hashsize is 31, ds_poolsize is 127, How to tune those two parameter, Do anyone has any guideline ? thanks.

The performance guide documentation has some guidelines, you could use then as baseline: "For medium to large systems, you can start with the following values: DD_HASHSIZE 503 DD_HASHMAX 4 DS_HASHSIZE 503 DS_POOLSIZE 1000Monitor these caches by running the onstat -g dsc command to see the actual usage, and you can adjust these parameters accordingly." Luis Marques DIT/TCS/DBA - Informix/Postgresql/Mysql/DB2 Database Administration tlf:+351 215018981 / tlm:+351 963135033 / prev:+351 962059165 luis-silvestre-marques@telecom.pt AV JACQUES DELORS EDF INOVACAO 3 TAGUSPARK 2740-122 PORTO SALVO | PORTUGAL meo.pt AVISO DE CONFIDENCIALIDADE Esta mensagem e quaisquer ficheiros anexos a ela contêm informação confidencial, propriedade da PT Portugal e/ou das demais sociedades que com ela se encontrem em relação de domínio, Fundação Portugal Telecom e PT ACS, destinando-se ao uso exclusivo do destinatário. Se não for o destinatário pretendido, não deve usar, distribuir, imprimir ou copiar este e-mail. Se recebeu esta mensagem por engano, por favor informe o emissor e elimine-a imediatamente. Obrigado. -----Original Message----- From: ids-bounces@iiug.org [mailto:ids-bounces@iiug.org] On Behalf Of CHUAN LU Sent: sexta-feira, 10 de novembro de 2017 03:02 To: ids@iiug.org Subject: contention on dstpool [40175] Hi, I run 'onstat -g spi | sort -nr -k 2 |head -20 , and the output show high contention on dstpool,currently the ds_hashsize is 31, ds_poolsize is 127, How to tune those two parameter, Do anyone has any guideline ? thanks. ******************************************************************************* Forum Note: Use "Reply" to post a response in the discussion forum.

Statement cache being used? That might save you some optimization work and lower this contention ... From: "CHUAN LU" <luchuan@cn.ibm.com> To: ids@iiug.org Date: 11/10/2017 04:02 AM Subject: contention on dstpool [40175] Sent by: ids-bounces@iiug.org Hi, I run 'onstat -g spi | sort -nr -k 2 |head -20 , and the output show high contention on dstpool,currently the ds_hashsize is 31, ds_poolsize is 127, How to tune those two parameter, Do anyone has any guideline ? thanks. ******************************************************************************* Forum Note: Use "Reply" to post a response in the discussion forum.