We've recently started running Oracle 10g on SLES9 We were wondering why we are going into swap with 16G of ram and not much running on the machine except for Oracle. Some things we found are:

Subject: Re : Why does system show all 16 GB used and swap also in use

Paul; Turn off disk cacheing, make sure that you are using async I/O.

HTH Peter

Subject: Re : Why does system show all 16 GB used and swap also in use

You're probably observing two phenomena here:

1. Linux will use as much memory as it can get for "disk caching" (filesystem buffers, really). You can reduce this dramatically using the BufferMem parameter, and by using async I/O. (As already noted...) 2. In most unixen, shared memory segments get counted multiple times. The executable code for each process is loaded into shared (sharable) memory, and the SGA is -- of course -- shared also. The memory consumed for the "oracle" executable and for the SGA are commonly reported for *all* processes that are using them, even though each is present in memory only once.

I search the Internet and find that the buffermem parameter is supposed to be in /proc/sys/vm but I also heard that some extensive work has been done on the virtual memory system in kernel 2.6. I don't have a buffermem parameter to set. Does anyone know how to adjust/turn-off disk caching in SLES9 with the 2.6 kernel? Thanks, Ed