Re: Systables in local cache (was: Correcting Next Extent problems).

}From: uunet!pyra.co.uk!graeme (Graeme Sargent) }Subject: Systables in local cache (was: Correcting Next Extent problems). }Date: 1 Mar 93 10:20:09 GMT }X-Informix-List-Id: <news.2727> }In <1993Feb23.160915.5802@informix.com> (Dave Kosenko) writes: }>Contrary to what the manuals lead you to believe, having more than 8 }>extents will not have any significant impact on the performance of your }>system. The reason 8 is used is that 8 extents are tracked in the }>tblspace shared memory structure. When there are >8, the tblspace }>tblspace page for the table will be checked. For frequently accessed }>tables, this will cause the TT page to sit in cache, so there is no great }>loss. For system tables, it is even less of a problem, because they are }>read into *local* cache when sqlturbo is started up, so accessing that }>data is really not an issue. }Are you saying that each sqlturbo process keeps a copy of the system }catalogs in it's stack segment, and therefore size of data dictionary }affects process size and memory usage per user???? No: the cache referred to was the main shared memory segment. }If this is true, how should one attempt to calculate the effect on memory }per user? N/A Yours, Jonathan Leffler (johnl@obelix.informix.com) #include <disclaimer.h>