[postgis-users] Poor performance

[David Mitchell]

> This says that its only taking 0.7 seconds - thats pretty good for 
> pulling 23,000 random rows off disk.

Ok, I'll give you that. But once those rows are in the page cache it 
should be a lot faster. The times you've got are for the cached run (the 
first time it is a lot slower).

> You could try re-building the index:

Not sure that that would help, this table hasn't changed since it was 
first indexed.

> The next step would be to get faster drives or RAID them - whats the CPU 
> doing during the query (if its not high, you're IO bound)?

This is running off two 10,000 rpm SATA drives in a striped RAID 
configuration. But again, this should be much faster for the cached run.

-- 
David Mitchell
Software Engineer
Telogis

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