Re: system cache and buffer cache

Praveen Kumar N wrote:
> Hi,
>     can anybody explain me what is the difference between system cache 
> and buffer cache?
>
> I found that keywords in PostgreSql FAQ 
> http://www.postgresql.org/docs/faqs.FAQ_DEV.html#item2.1

System cache is a per-row cache of system catalog tables. It's used to 
speed up lookup of things like function names. It's implemented in 
src/backend/utils/cache/syscache.c

Buffer cache is the cache managed by the buffer manager, that caches any 
blocks from any relation used in the system. All access to relations go 
through the buffer cache, using ReadBuffer/ReleaseBuffer (etc.) calls. 
It's implemented in src/backend/storage/buffer/bufmgr.c

--  Heikki Linnakangas EnterpriseDB   http://www.enterprisedb.com