Memory utilization (was SGA/PGA and virtual memory)

Hello,

In article <332A45D4.5714_at_shirenet.com>, Gus Spier <gus_at_shirenet.com> wrote:

GS> Has anybody used a technique called "pinning a package" in memory?
GS> The allegation is that if frequently used packages are "pinned" in the
GS> SGA, performance is improved.  Of course, the obvious trade off is that a
GS> portion (>10,000k) of memory will be unavailable for the rest of the
GS> database and users.  In return, Oracle will not have to call up the
GS> package, use it, and flush it when finished with it.
GS> Will the anticipated performance improvement be worth the commitment?

If the package is read from the filesystem and you have enough RAM for cache there is no need to pin it in memory. Once read file will stay in memory until you some other file will be read and there will be no available RAM. If you have enough RAM, frequently used files will stay in cache forever.

vmstat/vmtune utilities will be useful to watch and tune your VMM behaviour.

Best regards,
Cyril Received on Mon Mar 17 1997 - 00:00:00 CST