[dev] datatree performance (again)

[Kevin M. Myer]

Quoting Eric Jon Rostetter <eric.rostetter at physics.utexas.edu>:

> Quoting Didi Rieder <adrieder at sbox.tugraz.at>:
>
>>> With less users on the system (night time) the queries take less than
>>> a second. But with many (> 500) concurrent users they can take 8 sec.
>>> and more.
>
> One idea I had was that it might be a DB issue (mysql vs pgsql vs
> oracle, etc).
> The other idea people have expressed is that it is a concurrent user issue.
>
> I don't see any problems on my site, but I max out at 64 concurrent users.
> So maybe I don't have enough people hitting my site to trigger a melt down.
>
>> so it is about 100 queries / sec. on average in the last 21 days,
>> which include nighttime and holidays.
>
> Since it is no doubt much higher at peak, it could be just too many queries
> for the DB to handle...

Just to add some more data to the mix:

MySQL 4.1.X, InnoDB and MyISAM tables; about 30 databases total

Supports multiple Horde installs (12), but each install has a separate 
database; all Horde databases are MyISAM

The two largest concurrent users peak at 100 users and 60 users, 
respectively.  Our own install is the latter, so I'm pretty sure I'd 
pick up degradation since I use it on a daily basis.

I see no performance degradation, although these are fairly beefy 
database servers.

Kevin
-- 
Kevin M. Myer
Senior Systems Administrator
Lancaster-Lebanon Intermediate Unit 13  http://www.iu13.org