Re: pg_shmem_allocations view

Hi,

On 2014-05-04 13:44:17 +0200, Andres Freund wrote:
> postgres=# SELECT * FROM pg_shmem_allocations ORDER BY size DESC;
>                  key                 |     off     |    size     | allocated
> -------------------------------------+-------------+-------------+-----------
>  Buffer Blocks                       |   286242528 | 17179869184 | t
>  Buffer Descriptors                  |   152024800 |   134217728 | t
> ...
>  OldSerXidControlData                | 17584357344 |          16 | t
> (44 rows)

Thinking about this, I think it was a mistake to not add a 'name' field
to dynamic shared memory's dsm_control_item. Right now it's very hard to
figure out which extension allocated a dsm segment. Imo we should change
that before 9.4 is out. I am not suggesting to use it to identify
segments, but just as an identifier, passed in into dsm_create().

Imo there should be a corresponding pg_dynshmem_allocations to
pg_shmem_allocations.

Greetings,

Andres Freund

-- 
 Andres Freund	                   http://www.2ndQuadrant.com/
 PostgreSQL Development, 24x7 Support, Training & Services