Hello
2012/4/25 Venki Ramachandran <venki_ramachandran@yahoo.com>:
> Hi all:
> Can someone please guide me as to how to solve this problem? If this is the
> wrong forum, please let me know which one to post this one in. I am new to
> Postgres (about 3 months into it)
>
> I have PostGres 9.0 database in a AWS server (x-large) and a pgplsql program
> that does some computation. It takes in a date range and for one pair of
> personnel (two employees in a company) it calculates some values over the
> time period. It takes about 40ms (milli seconds) to complete and give me the
> answer. All good so far.
>
> Now I have to run the same pgplsql on all possible combinations of employees
> and with 542 employees that is about say 300,000 unique pairs.
>
> So (300000 * 40)/(1000 * 60 * 60) = 3.33 hours and I have to rank them and
> show it on a screen. No user wants to wait for 3 hours, they can probably
> wait for 10 minutes (even that is too much for a UI application). How do I
> solve this scaling problem? Can I have multiple parellel sessions and each
> session have multiple/processes that do a pair each at 40 ms and then
> collate the results. Does PostGres or pgplsql have any parallel computing
> capability.
no, PostgreSQL doesn't support parallel processing of one query. You
can use some hardcore tricks and implement cooperative functions in C
- but this is hard work for beginner. The most simple solution is
parallelism on application level.
Regards
Pavel Stehule
>
> Thanks, Venki