Re: Where best to cache the disk

In article 783604402snz_at_sambusys.demon.co.uk, psb_at_sambusys.demon.co.uk (Paul Beardsell) writes:
> We are not using raw partitions for our tablespaces.
> Are we better off caching inside Oracle by using a large SGA
> and a small Unix disk cache or should we use a small SGA and
> a large Unix disk cache?
>
> I am tempted to assign all our spare memory to the Unix disk
> cache (by increasing NBUF etc) and to keep the SGA just big
> enough for DC_* dictionary caching.
>
> What say you?

By assigning your cache at the file system level you will be caching resources other than those specifically allocated to Oracle. If you want to cache more Oracle data you should give more cache to the SGA. If, in turn, you want to improve I/O performance for the Unix environment as a whole you should consider allocating to the system.

There is a concise guide published by Oracle:

       Oracle for Unix Performance Tunning tips (Part # 53134-0293)

This guide, while somewhat old (1993) provides many pointers for Unix based performance optimization. it is by no means the ultimate but will give you many ideas for your own performance research.

John Baez Received on Thu Nov 10 1994 - 15:13:17 CET