Skip to main content

This site requires you to update your browser. Your browsing experience maybe affected by not having the most up to date version.

We've moved the forum!

Please use forum.silverstripe.org for any new questions (announcement).
The forum archive will stick around, but will be read only.

You can also use our Slack channel or StackOverflow to ask for help.
Check out our community overview for more options to contribute.

General Questions /

General questions about getting started with SilverStripe that don't fit in any of the categories above.

Moderators: martimiz, Sean, Ed, biapar, Willr, Ingo, swaiba

What is the most MySQL resource expensive operation or query a basic SS site can perform?


Go to End


835 Views

Avatar
vwd

Community Member, 166 Posts

4 December 2012 at 6:32pm

Hi,

Just wondering what the heaviest MySQL resource load operation is please?

My web host has upgraded MySQL Governor and it is now regularly clamping down on a few of the sites for excessive MySQL read volume.

For example, here is a log entry from MySQL Governor:

[Mon Dec 3 16:07:49 2012] XXXXXX LIMIT_ENFORCED period current value, 
field read value 5435850787/limit 1000000000 
restrict level 1 
loadavg(1.21 0.76 0.72 3/895 940326) 
vmstat( 1 4 108 443196 321808 2993108 0 0 143 127 1 0 9 7 80 4 0) cpu = 0.000000, 
read = 5435850787, write = 1671442879

What's quite bizarre is that the read value is actually 5435850787 bytes. What could possibly be causing a ~5GB read from MySQL? The site is having very low traffic at that time. Never more than 5 concurrent visitors. And outside the CMS, the site has a very straightforward DataModel - very basic.

I'd like to do an experiment by performing the most expensive operation(s) in SS and see what the MySQL Governor stats are to be sure that the Governor is reporting correctly - it seems to be orders of magnitude more than it should be.

Would a /dev/build?flush=all be very expensive? Any other suggestions?

Kind regards,
VWD.