April 19, 2014

MySQL Performance Blog gets new server.

Try number two. We have moved to the new server yet again, now it is server hosted by ServerBeach as recommended by Kevin Burton and few other guys. Lets hope this will run stable and we’ll not need to move it back in emergency in less than a week as we had to last time. […]

MySQL Master-Master replication manager released

The MySQL Master-Master replication (often in active-passive mode) is popular pattern used by many companies using MySQL for scale out. Most of the companies would have some internal scripts to handle things as automatic fallback and slave cloning but no Open Source solution was made available. Few months ago we were asked to implement such […]

Figuring out what limits MySQL Replication

Today I was cloning the master using LVM Snapshot and found it was taking quite a while to catch up, which highlighted replication could be the limiting factor for this system quite soon, so I decided to check what is limiting MySQL Replication speed. My first idea was to check it based on slow query […]

Percona Server with TokuDB: Packing 15TB into local SSDs

Two weeks ago we released an Alpha release of Percona Server with TokuDB. Right now I am on a final stage of evaluation of TokuDB for using in our project Percona Cloud Tools and it looks promising.

Introducing backup locks in Percona Server

TL;DR version: The backup locks feature introduced in Percona Server 5.6.16-64.0 is a lightweight alternative to FLUSH TABLES WITH READ LOCK and can be used to take both physical and logical backups with less downtime on busy servers. To employ the feature with mysqldump, use mysqldump –lock-for-backup –single-transaction. The next release of Percona XtraBackup will […]

How FLUSH TABLES WITH READ LOCK works with Innodb Tables

Many backup tools including Percona Xtrabackup, MyLVMBackup and others use FLUSH TABLES WITH READ LOCK to temporary make MySQL read only. In many cases the period for which server has to be made read only is very short, just few seconds, yet the impact of FLUSH TABLES WITH READ LOCK can be quite large because […]

Recovering Linux software RAID, RAID5 Array

Dealing with MySQL you might need to deal with RAID recovery every so often. Sometimes because of client lacking the proper backup or sometimes because recovering RAID might improve recovery, for example you might get point in time recovery while backup setup only takes you to the point where last binary log was backed up. […]

Aligning IO on a hard disk RAID – the Benchmarks

In the first part of this article I have showed how I align IO, now I want to share results of the benchmark that I have been running to see how much benefit can we get from a proper IO alignment on a 4-disk RAID1+0 with 64k stripe element. I haven’t been running any benchmarks […]

Aligning IO on a hard disk RAID – the Theory

Now that flash storage is becoming more popular, IO alignment question keeps popping up more often than it used to when all we had were rotating hard disk drives. I think the reason is very simple – when systems only had one bearing hard disk drive (HDD) as in RAID1 or one disk drive at […]

Battery Learning still problem many years after

The performance problems caused by battery auto learning go many years back. We wrote about it, other people from MySQL Community too. The situation did not get better, at least not with Dell RAID controllers, H700 and H800 have the same problem too. At the same time situation got worse as a lot more people […]