Re: 3 parameter/onstat questions

Thanks. I just got off the phone with Informix. They  told me that the change ( bc 2 ), doesn't change any of the existing chunks that are 2 gigs and less in size. It only works for new chunks created after it is applied. I guess that's why it works so quickly. ----- Original Message ----- Subject: Re: 3 parameter/onstat questions From: "Mark Jamison" >;majp51@yahoo.com> Date: Wed, April 9, 2008 15:56 Floyd Wellershaus >;floyd@fwellers.com> wrote: I just got off the chat-with-labs with John Miller. He left me with 3 questions I am hoping to get more info about, having failed to get anything useful from the version 10 docs. I'm on ids10.0.fc5. 1) He strongly recommended having the chunk mode set to expanded 'always'. He said that if it's not that way, I am suffering in performance because there is a translation that needs to go on with each IO between the old type of IO and the new type. ( something like that ).    --So is this correct for my version ?    -- If it is, then onmode -BC 2 would do it, is there any danger to that, or does it take a while , or is it instantaneous. ( yes I know I can check, but I would have to make an instance to check it on ). Hi Floyd, Answering the above. Yes, it is correct for your version. In addition to improving performance, it also means you use less memory, and can avoid certain issues that can arise if you run out of memory. In order to enable Expanded chunks, you have to first run onmode -BC 1 before trying to run onmode -BC 2. In practical usage, it takes zero time, and applies an in place style of change for the pages on disk. ------------------------------------------------------------------------------------ Praise the Lord oh my soul, let my inmost being praise His holy name. -Psalm 103:1