Re: shared memory/max_locks_per_transaction error

Tom, Alvaro:
Thank you much for the clarification. It's "back to the drawing board" for
me!

Kynn

On Mon, Mar 17, 2008 at 10:55 AM, Tom Lane <tgl(at)sss(dot)pgh(dot)pa(dot)us> wrote:

> "Kynn Jones" <kynnjo(at)gmail(dot)com> writes:
> > I'm leaning towards the re-design option, primarily because I really
> don't
> > really understand the consequences of cranking up
> max_locks_per_transaction.
> > E.g. Why is its default value 2^6, instead of, say, 2^15? In fact, why
> is
> > there a ceiling on the number of locks at all?
>
> Because the size of the lock table in shared memory has to be set at
> postmaster start.
>
> There are people running DBs with a couple hundred thousand tables,
> but I don't know what sorts of performance problems they face when
> they try to run pg_dump. I think most SQL experts would suggest
> a redesign: if you have lots of essentially identical tables the
> standard advice is to fold them all into one table with one more
> key column.
>
> regards, tom lane
>