October 24, 2014

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 […]

When (and how) to move an InnoDB table outside the shared tablespace

In my last post, “A closer look at the MySQL ibdata1 disk space issue and big tables,” I looked at the growing ibdata1 problem under the perspective of having big tables residing inside the so-called shared tablespace. In the particular case that motivated that post, we had a customer running out of disk space in his […]

High-availability options for MySQL, October 2013 update

The technologies allowing to build highly-available (HA) MySQL solutions are in constant evolution and they cover very different needs and use cases. In order to help people choose the best HA solution for their needs, we decided, Jay Janssen and I, to publish, on a regular basis (hopefully, this is the first), an update on […]

Changing an async slave of a PXC cluster to a new Master

Async and PXC A common question I get about Percona XtraDB Cluster is if you can mix it with asynchronous replication, and the answer is yes!  You can pick any node in your cluster and it can either be either a slave or a master just like any other regular MySQL standalone server (Just be […]

Feature in details: Incremental state transfer after a node crash in Percona XtraDB Cluster

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 […]

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 […]

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

Note: There is an updated post on this topic here. 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 […]