Re: pg_autovacuum: short, wide tables

"Matthew T. O'Connor" <matthew(at)zeut(dot)net> writes:
> Tom Lane wrote:
>> In particular, I think people would like to be able to use the stats
>> views to see how much toast-related I/O is going on, and not have that
>> smushed together with main-table I/O.

> Fair enough, but how are you planning to display the data,

At the moment I'm thinking "just like a regular table" --- see my
last message to Alvaro. The existing backend code will count each
toast-chunk insert or delete just like a normal row insert or delete,
so AFAICS this will produce sane-looking stats that autovac could
use the same way as for a plain table.

The main bit of additional logic that might be needed is an awareness
that firing a VACUUM on a main table will implicitly fire one on its
toast table, and so you'd not want to go and issue the toast table
VACUUM separately.

regards, tom lane