Reading the article published on MariaDB site about performance evaluation of MySQL 5.7 -vs- MariaDB 10.1 I've got a double feeling: from one side I have no any reason to have a doubt in obtained results, and from another side - my feeling says me there is something going odd.. But well, I don't have any attention to blame anybody (and sorry if you think so) -- my willing here is only to understand what is going on, why, and what are the challenges on the observed test workload(s). I'll cover here only my observations on the LinkBench workload as it was not yet enough tested and involving many questions around..

LinkBench Benchmark :

• developed by Facebook Team, so represents a true real life workload
• written in Java
• from the beginning since it creation was reported as …

How to configure SimpleMembership with MySql is explained in this post, as well as how to use OAuth with external providers to access an application providing external credentials.

Recently while working on geographical master slave replication we encountered an issue, where in peak hours replication slave lagging.

when we checked SHOW SLAVE STATUS value of Seconds_Behind_Master was jumping from 0 to a random high value, and then back to 0.

We also found this in the processlist of Master,

1366318 rpluser [IP Address]:15120  NULL  Binlog  Dump   9033    Writing to net  NULL

The status “Writing to net” means that MASTER is sending (or trying to send) data to SLAVE.

In a healthy replication, the status would be “Has sent all binlog to slave; waiting for binlog to be updated“.

It usually happens when MASTER-SLAVE geographically distributed in different data-center,network , and slow network.

Here limited network bandwidth was causing a problem , …

Fri, 2014-08-15 11:00anderskarlsson

MaxScale 1.0 from SkySQL is now in Beta and there are some cool features in it, I guess some adventurous people has already put it into production. There are still some rough edges and stuff to be fixed, but it is clearly close to GA. One thing missing though are something to manage starting and stopping MaxScale in a somewhat controlled way, which is what this blog is all about.

I have developed two simple scripts that should help you manage MaxScale in a reasonable way, but before we go into the actual scripts, there are a few things I need to tell you. To begin with, if you haven't yet downloaded MaxScale 1.0 beta, you can get it from MariaDB.com, just go to Resources->MaxScale and to get to the downloads you first need to register (which is free). Here are downloads to rpms and source, but if you are currently looking for a tarball, there …

August 15, 2014 By Severalnines

We're looking for an energetic and talented web developer to join our small but agile web team. This position is full-time and pay is negotiable. The hours are flexible and work can be done remotely.

Severalnines is a self-funded startup with a dozen employees; headquartered in Stockholm, Sweden and with a globally distributed, home-office based team. We provide automation and management software for database clusters. Our ClusterControl product is the leading management application for database clusters and is used by thousands of companies.

We were founded in 2010 and launched our product that same year, so you’ll be …

Twice each year members of the global open-source community converge on London in November and Santa Clara in April to network with, and learn from, some of the world’s most experienced and accomplished system architects, developers and DBAs.

And now it’s time for YOU to give back to this diverse and growing MySQL community. The Call for Speakers for Percona Live London (Nov. 3-4) closes Aug. 17 and the deadline for submitting talks for the ever-growing Percona Live MySQL Conference and Expo (April 13-16, 2015) expires Nov. 9.

If you like putting things off until the last minute, then it’s time to get to work! Aug. 17 is just two days away and November will be here before you know it (think of how fast summer has gone by already).

…

recently while working on MySQL cluster 7.3.5, we came across this error

Forced node shutdown completed. Caused by error 2341: 'Internal program error (failed ndbrequire)(Internal error, programming error or missing error message, please report a bug). Temporary error, restart node'.

The management nodes would start up but

the data nodes would complete phase 1 & shutdown, some times at phase 2 and some times at phase 5.

The error one would see in the trace file would be as follows:

Status: Temporary error, restart node
Message: Internal program error (failed ndbrequire) (Internal error, programming error or missing error message, please report a bug)
Error: 2341
Error data: CREATE_TABLE_REF
Error object: NDBCNTR (Line: 2493) 0x00000003
Program: ndbd

How did we resolve it ?

First, few of our data nodes had an incorrect connect-string

Second, we had pre-assigned NodeGroups for the data …

We've all heard the hype.  MySQL 5.6 is packed with amazing new features that address all our database problems.  5.6 deals with replication and HA and performance and monitoring and security and features.  It just may cure cancer.

In fact it's been out for ages.  It went GA  …

On Tuesday I gave a talk on Django at the London Django Meetup Group, titled “Django at Scale.” Here are my slides:

Here are a few brief summaries of topics I covered, which I hope to cover in more depth with a blog post on each in the future:

1. Wrap Django’s Classes For Your Project

Sub-classing django’s base classes, e.g. the Admin classes as in for, allows you to make whole codebase changes easily. It’s not that much effort to implement and allows you to solve many problems easily. It’s also an argument for class-based views. I’ve give a complete example of doing this in my post on extending querysets and the admin to return approximate counts.

2. Background-fill Your Cache

Virtual servers for MySQL are popular but are they the answer? Should we be containing our instances instead. An Updated Performance Comparison of
Virtual Machines and Linux Containers is an interesting study of using containers over VMs by four brilliant folk from IBM Research in Austin. There are several benefits to containers that are detailed in the study.

So what is wrong with VMs? IBM has been using them since the 1970s. Well, VMs have a static number of virtual CPUs (vCPU) and a fixed amount of RAM that bound performance. And each vCPU can only use up to one real CPUs of clock cycles. Since each VM is a Linux process, resource management like the scheduler come into play.

Containers? They are built on the kernel namespaces. A container acts like its own little Linux box but …