[Tilesathome] Using RAM-drive for ROMA temp tables

[Florian Lohoff]

On Sat, Dec 06, 2008 at 01:26:53AM +0100, Mathieu Arnold wrote:
> temp_buffers (integer)
> 
>     Sets the maximum number of temporary buffers used by each database
> session. These are session-local buffers used only for access to temporary
> tables. The default is eight megabytes (8MB). The setting can be changed
> within individual sessions, but only up until the first use of temporary
> tables within a session; subsequent attempts to change the value will have
> no effect on that session.
>     A session will allocate temporary buffers as needed up to the limit
> given by temp_buffers. The cost of setting a large value in sessions that
> do not actually need a lot of temporary buffers is only a buffer
> descriptor, or about 64 bytes, per increment in temp_buffers. However if a
> buffer is actually used an additional 8192 bytes will be consumed for it
> (or in general, BLCKSZ bytes). 
> 
> I've set my temp_buffers to 384M, and, I don't think one request will ever
> create temp tables that large :-) (128M was not, on the other hand, I
> believe, enough to store everything it would need.)

So you think there are z12 tiles whose binary table content has more
than 128M ? I dont think so - IIRC the largest xml of that binary i saw
was ~40MByte and the binary would most likely not exceed 4MByte for
that.

Flo
-- 
Florian Lohoff                  flo at rfc822.org             +49-171-2280134
	Those who would give up a little freedom to get a little 
          security shall soon have neither - Benjamin Franklin
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