MySQL data backup: going beyond mysqldump

A user on a linux user group mailing list asked about this, and I was one of the people replying. Re-posting here as I reckon it’s of wider interest. > [...] tens of gigs of data in MySQL databases. > Some in memory tables, some MyISAM, a fair bit InnoDB. According to my > understanding, [...]

Cache pre-loading on mysqld startup

The following quirky dynamic SQL will scan each index of each table so that they’re loaded into the key_buffer (MyISAM) or innodb_buffer_pool (InnoDB). If you also use the PBXT engine which does have a row cache but no clustered primary key, you could also incorporate some full table scans. To make mysqld execute this on [...]

A day in the life of Datacenter Disasters

Open Query currently hosts a large part of our infrastructure at Linode. We are extremely happy with their performance, stability and support. Unfortunately any chain is only as strong as it’s weakest link. This week, there was a major thunderstorm near the Hurricane Electric datacenter (anyone else think that name is funny in combination with [...]

Quest for Resilience: Multi-DC Masters

This is a Request for Input. Dual MySQL masters with MMM in a single datacentre are in common use, and other setups like DRBD and of course VM/SAN based failover solutions are conceptually straightforward also. Thus, achieving various forms of resilience within a single data-centre is doable and not costly. Doing the same across multiple [...]

relay-log-space-limit

We don’t often see this option configured (default: unlimited) but it might be a good idea to set it. What it does is limit the amount of disk space the combined relay logs are allowed to take up. A slave’s IO_Thread reads from the master and puts the events into the relay log; the slave’s [...]

Trivia: identify this replication failure

We got good responses to the “identify this query profile” question. Indeed it indicates an SQL injection attack. Obviously a code problem, but you must also think about “what can we do right now to stop this”. See the responses and my last note on it below the original post. Got a new one for [...]

MySQL University session Oct 22: Dual Master Setups With MMM

This Thursday (October 22nd, 13:00 UTC), Walter Heck (of Open Query) will present Dual Master Setups With MMM. MMM (Multi-Master Replication Manager for MySQL) is a set of flexible scripts to perform monitoring/failover and management of MySQL master-master replication configurations (with only one node writable at any time). Session slides (PDF). The toolset also has [...]

New Open Query training days in Australia

The favourite Open Query course modules as well as reworked and brand new ones, with November/December 2009 dates for Brisbane, Sydney, Canberra and Melbourne listed below. You can register for days/modules individually, to suit your time, budget and current needs. Your trainers are Sean, Ray and Arjen (see OQ people). For the Canberra and Melbourne [...]

Getting ready for FrOScon 2009

I arrived yesterday in St. Augustin, near Bonn in Germany. After a good day of hitchhiking (weather is beautiful here) I stayed with my Pakistani Couchsurfing host and we had an extremely interesting evening talking about the gigantic cultural differences between western civilization and Pakistani civilization. It beats staying in a hotel by about a [...]

Replication fail with “There is no ‘username’@’host’ registered”

This post doesn’t contain a tip, I’m asking the q and I don’t know the answer yet. Could just be a logic error on my part, in which case it was just a personal mystery and I thank you for helping! MySQL error 1449 “There is no ‘username’@’host’ registered” You can get a replication fail [...]