[Tilesathome] INNODB for tiles_meta?

[Andres Kaaber]

On Thursday 19 July 2007 21:57:26 Raphaël Jacquot wrote:
> OJW wrote:
> > What do people think of the idea of moving tiles_meta to InnoDB format
> > (is currently MyISAM)
> >
> > It currently has 24 million entries, in 3.2 GiB of disk, which (not being
> > a db expert) I guess will take a while to convert.
> >
> > tiles_meta is written-to for each upload (sometimes many times per
> > upload), and read (a) whenever someone asks for details of who uploaded a
> > tile and (b) when daily tile list is generated.
>
> this table using MyISAM is total nonsense. please convert it ASAP !!
>
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Well I'v been playing around a bit with db -s and I dont think converting it 
ASAP would be a good idea.
First of all, what will it give? MyISAM is considered a little bit faster then 
Innodb. Why mostly Innodb is is selected is because it enables the row level 
locking while MyISAM cant do that, only table locking.
One big disadvantage of innodb is the size:

http://dotnot.org/blog/archives/2005/10/12/mysql-myisam-vs-innodb/

"On the alpha server, using MyISAM, the entire database took about 2.4GB of 
disk space, including the indices. Once the load was done on the test server, 
the InnoDB files totaled over 10.6 GB!!! You’ve got that right, the 
FeedLounge grew to take up almost 5x the space just by changing database 
storage engines!"

So if right now the database is somewhere 3.2G then converting it to innodb 
would make more then 15G. 15G is a lot for making backups or what ever in 
this amount of data there will come in also the disks IO.

Well if you asked me ( :) ) then I'd say that maybe it's wise to switch DB 
from mysql to oracle. If this project becomes really popular then it is quite 
possible that db size will grow to few hundred G -s and I'm quite sure that 
MySQL nor postgres or sybase (ok maybe sybase but oracle surely would behave 
better) cant handle that.

We are using this one Oracle 10g XE
http://www.oracle.com/technology/products/database/xe/index.html

I'v been making php web apps on oracle for my company for a while now and it 
is great. And it is quite easy to convert your mysql syntax to oracles. 

Just my 0.2 € cents :)

-- 
Andres Kaaber
IT ja sidebüroo juhataja
Ida-Eesti päästekeskus
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