With our newest release of Percona XtraDB Cluster, I would like to highlight a very nice ability to recovery a node and bring it back to the cluster with an incremental transfer after a crash. This feature was available even in previous release, but now I want to give some details. So, MySQL crashes from [...]
Feature in details: Incremental state transfer after a node crash in Percona XtraDB Cluster
Understanding Multi-node writing conflict metrics in Percona XtraDB Cluster and Galera
I have addressed previously how multi-node writing causes unexpected deadlocks in PXC, at least, it is unexpected unless you know how Galera replication works. This is a complicated topic and I personally feel like I’m only just starting to wrap my head around it. The magic of Galera replication The short of it is that Galera [...]
Percona XtraDB Cluster 5.5.20 – Beta release
I am happy to announce the availability of beta release of our new product Percona XtraDB Cluster. Percona XtraDB Cluster is High Availability and Scalability solution for MySQL Users and the beta release is based on Percona Server 5.5.20 and the recently released Galera 2.0 GA The main focus in this release: Incremental State Transfer, [...]
Percona Server 5.5.15 + Galera 21.1-beta2
Codership team published beta2 of MySQL 5.5.15 with Galera replication https://launchpad.net/codership-mysql and we made port to Percona Server: source code: lp:~percona-dev/percona-server/percona-server-galera-5.5.15 binaries for RedHat/CentOS 6: http://www.percona.com/downloads/TESTING/Galera/Percona-XtraDB-Galera-5.5.15.tar.gz What difference between Percona Server+Galera and MySQL 5.5.15 ? First of course, Percona Server+Galera is based on our XtraDB engine. Second, we provide wsrep_sst_xtrabackup script, which allows to use [...]
READ-COMMITED vs REPETABLE-READ in tpcc-like load
Question what is better isolation level is poping up again and again. Recently it was discussed in InnoDB : Any real performance improvement when using READ COMMITED isolation level ? and in Repeatable read versus read committed for InnoDB . Serge in his post explains why READ COMMITED is better for TPCC load, so why [...]
SSD, XFS, LVM, fsync, write cache, barrier and lost transactions
We finally managed to get Intel X25-E SSD drive into our lab. I attached it to our Dell PowerEdge R900. The story making it running is worth separate mentioning – along with Intel X25-E I got HighPoint 2300 controller and CentOS 5.2 just could not start with two RAID controllers (Perc/6i and HighPoint 2300). The [...]
Innodb Performance Optimization Basics
Interviewing people for our Job Openings I like to ask them a basic question – if you have a server with 16GB of RAM which will be dedicated for MySQL with large Innodb database using typical Web workload what settings you would adjust and interestingly enough most people fail to come up with anything reasonable. [...]
MySQL Users Conference – Innodb
It might look like it is too late to write about stuff happened at Users Conference but I’m just starting find bits of time from processing accumulated backlog. The Theme of this Users Conference was surely Storage Engines both looking at number of third party storage engine presented, main marketing message – Storage Engine partnership [...]
Test Drive of Solid
Not so long ago Solid released solidDB for MySQL Beta 3 so I decided now is time to take a bit closer look on new transactional engine for MySQL. While my far goal is the performance and scalability testing before I wanted to look at basic transactional properties such as deadlock detection, select for update [...]
SELECT LOCK IN SHARE MODE and FOR UPDATE
Baron wrote nice article comparing locking hints in MySQL and SQL Server. In MySQL/Innodb LOCK IN SHARE MODE and SELECT FOR UPDATE are more than hints. Behavior will be different from normal SELECT statements. Here is simple example:

