Comments on: MySQL for Hosting Providers – how do they manage ?

By: peter

peter — Thu, 12 Feb 2009 20:03:11 +0000

Alex,

If you produce high load the best is to get dedicated server or VPS (where resource control is enforced).

By: Alex Price

Alex Price — Thu, 12 Feb 2009 15:04:37 +0000

I was with host monster but they kicked us off because our mysql queries were too long. Do you know of a web hosting place where we can have longer queries

By: peter

peter — Wed, 10 Dec 2008 04:50:22 +0000

Steven,

What do you mean ? With SQL injection you can do all kind of nasty stuff.

By: Steven Roussey

Steven Roussey — Wed, 10 Dec 2008 03:33:41 +0000

Could that example be used in a fashion for a sql injection?

By: Log Buffer

Log Buffer — Fri, 05 Dec 2008 21:40:42 +0000

Peter Zaitsev of the MySQL Performance Blog wondered how do MySQL hosting providers manage, when MySQL (including the 5.1 release) offers so little by way of resource limiting of users. -- Log Buffer #126

By: peter

peter — Tue, 02 Dec 2008 03:03:59 +0000

I agree,

Private MySQL, Private apache etc is better. It is just question of resources. Can you run few hundreds or thousands of such instances per box ? And this is low cost market we look at in this case.

By: Scott Yang

Scott Yang — Tue, 02 Dec 2008 02:38:31 +0000

One web hosting company that I host with (NearlyFreeSpeech.NET) gives a private instance of MySQL server to each customers (listening on standard port on a private IP address). It provides much better isolation than everyone shares the same MySQL process.

By: peter

peter — Sat, 29 Nov 2008 19:50:25 +0000

Michael,

mytop etc is good interactive tool You can sit and watch it but it is not productive use of your time especially if you have 100+ servers. I would say you can do the following

1) Have a script which will catch kill and report bad queries (taking too much). When you can aggregate them to see if particular users are guilty. This is often done together with watching loadavg or other hosting metric. During low load you can just let queries run but in case server is overloaded you’ve got to find a victim.

2) Slow Query log (w up to microsecond resolution) are great to find out slow queries and queries causing the load… post factum. Really helps if your goal to help users to reduce the load rather to punish them.

3) Google User Statistics found in Percona Extensions are very good way to monitor the load on per user and per table basics.

Nothing of this deals with memory resource usage though.

By: Michael

Michael — Sat, 29 Nov 2008 13:51:15 +0000

I actually work for a hosting company and I’m not sure exactly how our monitoring team catches things but mytop is a very useful application along with the process list and slow query logs, etc.

By: peter

peter — Sat, 29 Nov 2008 07:20:40 +0000

Tom,

This was example. Sure you can see SLEEP in processlist but What if you would do the sleep in the application instead ? Try it and try to catch things in the processlist Also note it does not have to be pure SET assignment, you can create user variable as a side effect of the query to obfuscate things.

As I mentioned before dealing with complex individual queries is easy… And this is most typical unintentional way to overload MySQL

The Shell Access/PHP Access etc is solved on the different level – the process accounting, the MySQL is however single process shared by many users which makes it hard.

Regarding Shared Hosting… it has its set and the price point. If you’re selling hosting for $5-10 a month you can’t really get VPS running as it will take too much overhead.