From: | Ondrej Ivanič <ondrej(dot)ivanic(at)gmail(dot)com> |
---|---|
To: | pgsql-general(at)postgresql(dot)org |
Subject: | Re: Postgres vs other Postgres based MPP implementations |
Date: | 2011-11-08 10:36:47 |
Message-ID: | CAM6mieLSbgXkynXa_fu-sn1KoUF3HvaPNGKEvcXvrM80rmtC_A@mail.gmail.com |
Views: | Raw Message | Whole Thread | Download mbox | Resend email |
Thread: | |
Lists: | pgsql-general |
Hi,
2011/11/8 Craig Ringer <ringerc(at)ringerc(dot)id(dot)au>:
> "Spreads reads too much" ?
>
> Are you saying there's too much random I/O? Is it possible it'd benefit from
> a column store?
> When you're using Greenplum are you using "Polymorphic Data Storage" column
> storage "WITH (orientation=column)" ?
yes, exactly. Column store and compression speed up queries even more
(sometimes beyond 100x times) comparing to postgres.
>
> Or is the performance different just in better utilisation of the hardware
> under Greenplum?
>>
Yes, looks like that they can better utilise available hardware.
>> Is there
>> a way to get PG backed IO stats using stock CentOS (5.7) kernel and
>> tools? (I can't change my env easily)
>
> Dunno; check postgresql high performance (book), the manual, etc. Useful
> tools are the pg_stat_ tables, "vmstat", "iostat", "iotop", etc.
Yeah, I know about those.. I like iotop but enterprise distributions
do not ship fresh kernels... I need something which can I "safely"
(slightly worse performance is acceptable but machine must survie) run
in production for several hours and then cross reference it with
postgres and other system logs
> That said, Pg's codebase isn't exactly trivial :S and trying to get involved
> in major re-engineering like parallelisation isn't going to be practical
> when you're just getting started.
That's what I meant ;)
--
Ondrej Ivanic
(ondrej(dot)ivanic(at)gmail(dot)com)
From | Date | Subject | |
---|---|---|---|
Next Message | Fujii Masao | 2011-11-08 10:54:05 | Re: Streaming Replication woes |
Previous Message | Lucas Mocellin | 2011-11-08 10:34:10 | Re: Performance Problem with postgresql 9.03, 8GB RAM,Quadcore Processor Server--Need help!!!!!!! |