Re: Load Distributed Checkpoints, take 3 - Mailing list pgsql-patches

From Greg Smith
Subject Re: Load Distributed Checkpoints, take 3
Date
Msg-id Pine.GSO.4.64.0706251743540.2936@westnet.com
Whole thread Raw
In response to Re: Load Distributed Checkpoints, take 3  (Heikki Linnakangas <heikki@enterprisedb.com>)
List pgsql-patches
On Mon, 25 Jun 2007, Heikki Linnakangas wrote:

> It only scans bgwriter_lru_percent buffers ahead of the clock hand. If the
> hand isn't moving, it keeps scanning the same buffers over and over again.
> You can crank it all the way up to 100%, though, in which case it would work,
> but that starts to get expensive CPU-wise.

In addition to being a CPU pig, that still won't necessarily work because
the way the LRU writer ignores things with a non-zero usage_count.  If
it's dirty, it's probably been used recently as well.

--
* Greg Smith gsmith@gregsmith.com http://www.gregsmith.com Baltimore, MD

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