=?ISO-8859-1?Q?R=E9my_Beaumont?= <remyb(at)medrium(dot)com> writes:
> On 30-Aug-05, at 12:15, Tom Lane wrote:
>> I know zip about NetApps, but doesn't the 8th column indicate pretty
>> steady disk reads?
> Yes, but they are very low.
Sure, but that's more or less what you'd expect if the thing is randomly
seeking all over the disk :-(. Just because it's a NetApp doesn't mean
it's got zero seek time.
You did not say what sort of query this is, but I gather that it's doing
an indexscan on a table that is not at all in index order. Possible
solutions involve reverting to a seqscan (have you forced the planner to
choose an indexscan here, either directly or by lowering random_page_cost?)
or CLUSTERing the table by the index (which would need to be repeated
periodically, so it's not a great answer).
regards, tom lane
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