Hi,
I am just realizing a totally RAM present MySQL-Database by tuning all buffers and caches
Now I am wondering if it would be possible to add sqlite-support to moodle (adodb has). The idea is to store the sqlite-database inside a ramdisk - one file can be easily backuped frequently to hdd - this should give a "little" more power and breath to the I/O-System. It should be possible to "stress" the CPU more, which is normally boring in ourdays.
We are not talking about extremly huge databases (0.5-1.0 GB). Before I'll start I just want to know if this idea is totally crazy or not and just one or two hints where to begin...
regards,
Maik
It's a great idea, and quite doable too. Have a look at the lib/xmldb directory. But be aware: it'll be great for small single installs, with one or two users (like Moodle-on-a-stick cases, or the MoodleClient project).
sqlite has good performance with a single user, but does not scale at all well with concurrency - writes lock the db. And web applications see a lot of concurrency.
So the benefits I'd expect of a SQLite support layer in XMLDb are a bit different -- and it'll be great if you can do it!
OTOH, if you are wanting to have a really fast MySQL on a RAM disk, you can do that too. Just move the mysql storage directory to a RAM disk.
As with the sqlite-on-a-ramdisk plan you do need a way to copy it to a real disk too -- or you'll just lose the data!
sqlite has good performance with a single user, but does not scale at all well with concurrency - writes lock the db. And web applications see a lot of concurrency.
So the benefits I'd expect of a SQLite support layer in XMLDb are a bit different -- and it'll be great if you can do it!
OTOH, if you are wanting to have a really fast MySQL on a RAM disk, you can do that too. Just move the mysql storage directory to a RAM disk.
As with the sqlite-on-a-ramdisk plan you do need a way to copy it to a real disk too -- or you'll just lose the data!
I had a look for the unsupported features of sqllite last time it came up:
http://www.sqlite.org/omitted.html
There are a few which might cause a problem in moodle - a few RIGHT OUTER JOINs, and also lots of column dropping etc on upgrade.
http://www.sqlite.org/omitted.html
There are a few which might cause a problem in moodle - a few RIGHT OUTER JOINs, and also lots of column dropping etc on upgrade.
Hi.
I'm working on the SQLite support for Moodle (and more) as one of the GSoC 2008 projects. My mentor is Penny Leach. You can found our specification at
http://docs.moodle.org/en/Student_projects/SQLite.
Please provide any comments you consider appropriate.
Regards,
Andrei
I'm working on the SQLite support for Moodle (and more) as one of the GSoC 2008 projects. My mentor is Penny Leach. You can found our specification at
http://docs.moodle.org/en/Student_projects/SQLite.
Please provide any comments you consider appropriate.
Regards,
Andrei