Re: pg_relation_size locking

Andreas Pflug <pgadmin@pse-consulting.de> writes:
> Until recently, pg_relation_size used SearchSysCache to locate the 
> relation to examine, and calculated the file location from that 
> information. Starting with dbsize.c V1.5 (committed after Beta2), 
> relation_open(.., AccessShareLock) is used. This is very unfortunate 
> because it will not allow to observe a table growing while it is 
> populated, e.g. with a lengthy COPY; pg_relation_size will be blocked. 

Nonsense.

> After reverting to 1.4, everything was fine again.
> Can we have this reverted/fixed?

Can we have the actual problem explained?
        regards, tom lane