Amit,

As a starter, if the server has 1 TB of shared memory, it is a bit stupid to use only only 38 Gb (not even 4% of the server's RAM...)I was going to say check you Buffer Turnover ratio before anything, but Art was still awake to answer that ( and he is the author of the formula ). This ratio will tell you if you need more BUFFERPOOL, but I am sure you do in a mean way.

How many users on the server? SHMVIRTSIZE will mainly depend on how many users are connected, then on how their queries consume shmvirt. To tune it, if possible, set an initial value, a bit short, and see how many additional segments get assigned during the day. This will be the 'cruising' value or initial value you will want to set for the server.

But you can have many possible reasons for slowness. Badly written queries, lack of indexes or bad indexes as a starter.

Eric VercellettoData Management Architect and Owner / Begooden IT ConsultingBoard of Directors, International Informix Users groupIBM Champion 2013,2014,2015,2016,2017,2018,2019,2020

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