limited number of mysql connections
2 post(s),
2 voice(s)
alexis perrier
2 post(s)
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My account has a max_user_connections of 10. However, I have a feeling that this is an issue that will creep up on me at the worst of times and I would like to take preventive steps. 1) why are we allowed so few connections ? is there a way to increase the max_user_connections for my account ? Mysql documentation talks about 150 default connection. Quote : “Beginning with MySQL 5.1.15, its default value is 151 to improve performance when MySQL is used with the Apache Web server. (Previously, the default was 100.)” 2) How can I prevent running out of connections before it happens ? Thanks |
Rahoul Baruah
Administator
31 post(s)
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Hi, Most people use our shared MySQL cluster (sqlreadwrite.brightbox.net). Because it is shared, we limit the number of connections per user – to prevent one user from hogging all the resources. We grant extra connections based upon the Brightboxes you have – a 256 box has 5, a 512 has 10 and so on (these are listed here: http://www.brightbox.co.uk/rails-hosting-pricing) – so people with bigger boxes have more connections to play with. Ordinarily a single mongrel or passenger process should only use a single connection. Occasionally passenger can keep extra connections open as it goes through a graceful restart (it holds old processes open till they are complete whilst simultaneously starting new ones) – however, this is pretty rare. At present, the only way to get extra connections is to buy another box (or upgrade to a larger one). However, as an alternative, you could install a local copy of MySQL onto your own box (although you lose the failover that our cluster provides); as this is exclusive to you, you are free to use it how you wish. Another alternative is to buy one of our managed MySQL clusters – this effectively gets you the same as the shared cluster (failover, backups etc), but all to yourself. Hope that helps, Rahoul. |