Re: fragmented system tables

Richard Stanford wrote: > > Sven Tolkemit schrieb: > > > we discovered, that the system tables (systables,sysindexes, etc.) on > > our Online 7.23.UC1 are very fragmented. We think, this leads into > > Volker Fraenkle wrote: > > > Yes, there is. You have to unload and drop the tables. After, you can > > create it with "first size" and "next size" (to prevent your tables from > > high fragmentation) and load the tables. > > John Carlson wrote: > > > Unless something has changed, should you do this with system tables? > > I've never tried to drop and recreate a system table before. > > > > Last I heard, this is a big no-no. > > What you can do is take a dbexport, go in and modify the schema to set the > NEXT size for all the system tables at the top. This way, they all go into > two extents, but hopefully no more. I never bothered to do any serious > benchmarking of this, and usually don't do it, but it is (as far as I know) > the only safe way of reducing extent sizes in system tables. > > Has anyone benchmarked this? I'd imagine better results in larger > systems (1000+ tables, etc). This won't work either since the system tables are created along with the database and are not contained in the schema file that dbexport produces. Art S. Kagel