Question on lots of small databases

I have a question but need to explain the scenario first. We have a 4 processor SGI with about 20GB of disk space The application is run on app servers that query the databases as multiple connections of the same user. we run 2 instances of IDS7.x Each instance has about 400 databases on it, the databases are relatively small. Querys are all simple and index based. Each user opens 2 database connections on startup and they remain open until done. The problem is that the load on the machine goes very high with only 20-30 users. It is not an indexing problem, the disks are striped RAID0 with high speed caching controllers. We do have to use cooked disk space because of the 2Gb limit....the SGI only allows 15 logical volumes ( We have .5Tb of diskspace) We do not appear to be disk bound. My question is due to the large number of databases we have is it possible that I am overlooking a kernel parameter that should be higher. I see a lot of long spins and a lot of mutexes. TIA for your assistance and as usual theres a free site membership for the first correct answer...if you want it :) Mike South The BEST in adult Video www.mikesouth.com

Post your ONCONFIG file and someone may spot something. Just a stab - are you using mostly network connections in CPU VPs? Or does the service for shared memory match the one used for TCP in the sqlhosts file? Either of these conditions can cause excessive system calls and CPU usage. Art S. Kagel Mike South wrote: > > I have a question but need to explain the scenario first. > > We have a 4 processor SGI with about 20GB of disk space > The application is run on app servers that query the databases as > multiple connections of the same user. > > we run 2 instances of IDS7.x > > Each instance has about 400 databases on it, the databases are > relatively small. Querys are all simple and index based. Each user > opens 2 database connections on startup and they remain open until > done. > > The problem is that the load on the machine goes very high with only > 20-30 users. It is not an indexing problem, the disks are striped > RAID0 with high speed caching controllers. We do have to use cooked > disk space because of the 2Gb limit....the SGI only allows 15 logical > volumes ( We have .5Tb of diskspace) We do not appear to be disk > bound. > > My question is due to the large number of databases we have is it > possible that I am overlooking a kernel parameter that should be > higher. I see a lot of long spins and a lot of mutexes. > > TIA for your assistance and as usual theres a free site membership for > the first correct answer...if you want it :) > > Mike South > The BEST in adult Video > www.mikesouth.com