Re: [v9.1] sepgsql - userspace access vector cache

On Thu, Jul 21, 2011 at 4:00 AM, Yeb Havinga <yebhavinga@gmail.com> wrote:
> Is there a way to dump syscache statistics like there is for
> MemoryContext..Stats (something - gdb helped me there)?

I don't know of one.

> Besides that I have to admit having problems understanding why the 5MB cache
> for pg_seclabel is a problem; it's memory consumption is lineair only to the
> size of the underlying database.  (in contrast with the other cache storing
> access vectors which would have O(n*m) space complexity if it wouldn't
> reclaim space). So it is proportional to the number of objects in a database
> and in size it seems to be in the same order as pg_proc, pg_class and
> pg_attribute.

Fair enough.  I'm not convinced that the sheer quantity of memory use
is a problem, although I would like to see a few more test results
before we decide that definitively.  I *am* unwilling to pay the
startup overhead of initializing an extra 2048 syscache that only
sepgsql users will actually need.

--
Robert Haas
EnterpriseDB: http://www.enterprisedb.com
The Enterprise PostgreSQL Company