Re: COPY Performance

On Mon, May 5, 2008 at 9:03 AM, Scott Marlowe <scott.marlowe@gmail.com> wrote:
> On Sun, May 4, 2008 at 5:11 PM, Hans Zaunere <lists@zaunere.com> wrote:
>  > Hello,
>  >
>  >  We're using a statement like this to dump between 500K and >5 million rows.
>  >
>  >  COPY(SELECT SomeID FROM SomeTable WHERE SomeColumn > '0')
>  >   TO '/dev/shm/SomeFile.csv'
>
>  Wait, are you really creating a .csv file in shared memory?  Can such
>  a thing even work?
>
>  If you're not creating a file in /dev/shm, where is it being built?
>  On the main OS drive?  the battery backed cached RAID array?

OK, looked it up.  you're making your .csv file in a ramdisk?  If it
gets big it's gonna make the machine start swapping.  i'd suggest
storing only small things in a ram disk really.  Other than that, I'm
not sure what the problem is.