On Wed, 9 Feb 2005 22:07:19 +0100, Hannes Rohde <[EMAIL PROTECTED]> wrote: > Hi all, > > We use MySQL as a database backend on a portal site. We have a two > database server setup (one master, one slave). The master is a PIV 3,2 GHz., > 2 GB Ram and a 80GB Raid-1 system. The slave is a PIV 3.2 GHz., 4 GB Ram and > a 80GB Raid-0 system. Both run on MySQL 4.1.9 and only use InnoDB. Even > though the slave is a bigger system and is quite fast with selects, it > always falls behind in replication (Seconds behind the server keeps growing > at high-load times). > Is there any way to speed up the replication a little more? I have already > tried a whole lot of things but have never been successful, yet :-(
Your config settings suggest you are using innodb. That can be problematic since innodb allows much higher concurrency than myisam, although you can still have this issue with myisam. What you have to realize is that due to how mysql replication works, every transaction needs to be serialized. The slave is only running a single statement at once. So if you have multiple CPUs on the server, or multiple disks that can't be saturated by a single concurrent operation ... then multiple simultaneous operations can get better performance on the server than you can get in replication to the client. If most of your stuff is innodb, then setting the innodb option to not sync to disk on every transaction may speed things up a lot ... if you don't care about your data. But, then again, I don't think mysql replication is actually fully transactional yet anyway. -- MySQL General Mailing List For list archives: http://lists.mysql.com/mysql To unsubscribe: http://lists.mysql.com/[EMAIL PROTECTED]
