Re: Memory Issue with array_agg?

Hello

please, can you send some example or test?

Regards

Pavel Stehule

2013/8/19 Robert Sosinski <rsosinski(at)ticketevolution(dot)com>

> When using array_agg on a large table, memory usage seems to spike up
> until Postgres crashes with the following error:
>
> 2013-08-17 18:41:02 UTC [2716]: [2] WARNING: terminating connection
> because of crash of another server process
> 2013-08-17 18:41:02 UTC [2716]: [3] DETAIL: The postmaster has commanded
> this server process to roll back the current transaction and exit, because
> another server process exited abnormally and possibly corrupted shared
> memory.
> 2013-08-17 18:41:02 UTC [2716]: [4] HINT: In a moment you should be able
> to reconnect to the database and repeat your command.
>
> I've definitely isolated it down to using array_agg, as when I changed the
> query to use string_agg, it worked fine. I also tried using array_agg on a
> few different queries, all yielding the same issue. Swapping in string_agg
> fixed the issue once more.
>
> This particular table has over 2 million rows and is 1.2 Gigs, and when I
> ran the query while viewing htop, the virtual size of the Postgres
> process ballooned to 13.9G until crashing.
>
> The version of Postgres I am using is: PostgreSQL 9.2.4 on
> x86_64-unknown-linux-gnu, compiled by gcc (Ubuntu/Linaro 4.7.2-2ubuntu1)
> 4.7.2, 64-bit
>
> Any help would be much appreciated, thanks!
>
> -Robert
>