Re: strange performance regression between 7.4 and 8.1

* Alex Deucher:

> I have noticed a strange performance regression and I'm at a loss as
> to what's happening.  We have a fairly large database (~16 GB).

Sorry for asking, but is this a typo?  Do you mean 16 *TB* instead of
16 *GB*?

If it's really 16 GB, you should check if it's cheaper to buy more RAM
than to fiddle with the existing infrastructure.

> however the table structure is almost identical (UTF8 on the new one
> vs. C on the old).

Locale settings make a huge difference for sorting and LIKE queries.
We usually use the C locale and SQL_ASCII encoding, mostly for
performance reasons.  (Proper UTF-8 can be enforced through
constraints if necessary.)

--
Florian Weimer                <fweimer@bfk.de>
BFK edv-consulting GmbH       http://www.bfk.de/
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