Mailing List Archive

Jimbo wrote:

>Ian Gilfillan, author of Mastering MySQL 4, has also volunteered to
>help, and if he wants access, we can give it to him too, even though I
>don't know him. He wrote a book, so he's legit.

There's no better source of legitimacy, in my eyes.
--
--------------------------------
| Sheldon Rampton
| Editor, PR Watch (www.prwatch.org)
| Author of books including:
| Friends In Deed: The Story of US-Nicaragua Sister Cities
| Toxic Sludge Is Good For You
| Mad Cow USA
| Trust Us, We're Experts
--------------------------------

After looking at Sheldon's website, it's a good thing I didn't claim to have
appeared as an expert on the radio!

Anyway, I've had a look at the my.cnf file, and the settings mostly look
fine. A couple of things...

set-variable = innodb_buffer_pool_size=384M
#set-variable = innodb_buffer_pool_size=512M

I see you've reduced this, probably because it was too high with the dual
db/web server. This can be upped to at most 80% of available memory when you
move to the dedicated server running InnoDB tables (you'd need to make sure
any MyISAM tables don't steal memory too - it's more complicated running
both table types - I haven't had a real look at the db structure yet to
say). This sets the cache size for innodb indexes etc, so upping it can help
quite a bit if this is the bottleneck.

Also:
set-variable = innodb_log_file_size=5M

This can go up to around 25% of the innodb_buffer_pool_size. Saves a bit of
disk I/O (at the cost of recovery speed after a crash)

The main speed increase I think will come from looking at individual
queries, and making sure the indexes are optimized. There was mention of one
query taking 37 seconds which should never happen!

If you have any really problematic queries, feel free to post them and I'll
see if I can take a look. I've downloaded the db from the site (hopefully
the structures etc are up to date), so I can see if there's anything I can
do to speed them up.

ian gilfillan

----- Original Message -----
From: "Sheldon Rampton" <sheldon.rampton@verizon.net>
To: <wikitech-l@wikipedia.org>
Sent: Friday, February 07, 2003 3:36 PM
Subject: [Wikitech-l] Re: Giving Jan access


> Jimbo wrote:
>
> >Ian Gilfillan, author of Mastering MySQL 4, has also volunteered to
> >help, and if he wants access, we can give it to him too, even though I
> >don't know him. He wrote a book, so he's legit.
>
> There's no better source of legitimacy, in my eyes.
> --
> --------------------------------
> | Sheldon Rampton
> | Editor, PR Watch (www.prwatch.org)
> | Author of books including:
> | Friends In Deed: The Story of US-Nicaragua Sister Cities
> | Toxic Sludge Is Good For You
> | Mad Cow USA
> | Trust Us, We're Experts
> --------------------------------
> _______________________________________________
> Wikitech-l mailing list
> Wikitech-l@wikipedia.org
> http://www.wikipedia.org/mailman/listinfo/wikitech-l
>

On ven, 2003-02-07 at 06:25, Ian Gilfillan wrote:
> Also:
> set-variable = innodb_log_file_size=5M
>
> This can go up to around 25% of the innodb_buffer_pool_size. Saves a bit of
> disk I/O (at the cost of recovery speed after a crash)

I did at one point try to increase this, but got an error on startup
about the log file not being the expected size and ended up changing it
back. (Sorry, I don't have the exact error message at hand -- for
shame!)

Is there any trick to fiddling with this setting?

(Just checked in to turn on the slow query logging now that the backup
dump run is finished. Back to the grindstone...)

-- brion vibber (brion @ pobox.com)