Re: Re: Postgres insert performance and storage requirement compared to Oracle

On Wed, Oct 27, 2010 at 6:13 AM, Ivan Voras <ivoras(at)freebsd(dot)org> wrote:
> On 10/26/10 17:41, Merlin Moncure wrote:
>> On Tue, Oct 26, 2010 at 11:08 AM, Leonardo Francalanci <m_lists(at)yahoo(dot)it> wrote:
>>>> temp  tables are not wal logged or
>>>> synced.  Periodically they can be flushed  to a permanent table.
>>>
>>>
>>> What do you mean with "Periodically they can be flushed  to
>>> a permanent table"? Just doing
>>>
>>> insert into tabb select * from temptable
>>>
>>
>> yup, that's exactly what I mean -- this will give you more uniform
>
> In effect, when so much data is in temporary storage, a better option
> would be to simply configure "synchronous_commit = off" (better in the
> sense that the application would not need to be changed). The effects
> are almost the same - in both cases transactions might be lost but the
> database will survive.

right -- although that's a system wide setting and perhaps other
tables still require full synchronous fsync. Still -- fair point
(although I bet you are still going to get better performance going by
the temp route if only by a hair).

merlin