In this blog post, we will discuss MySQL performance on eXFlash DIMMs. Earlier we measured the IO performance of these storage devices with sysbench fileio.

Environment

The benchmarking environment was the same as the one we did sysbench fileio in.

CPU: 2x Intel Xeon E5-2690 (hyper threading enabled)
FusionIO driver version: 3.2.6 build 1212
Operating system: CentOS 6.5
Kernel version: 2.6.32-431.el6.x86_64

In this case, we used a separate machine for testing which had a 10G ethernet connection to this server. This server executed sysbench. The client was not the bottleneck in this case. The environment is described in greater detail at the end of the blog post.

Sysbench OLTP write workload

…

HAProxy is frequently used as a software load balancer in the MySQL world. Peter Boros, in a past post, explained how to set it up with Percona XtraDB Cluster (PXC) so that it only sends queries to available nodes. The same approach can be used in a regular master-slaves setup to spread the read load across multiple slaves. However with MySQL replication, another factor comes into play: replication lag. In this case the approach mentioned for Percona XtraDB Cluster does not work that well as the check we presented only returns ‘up’ or ‘down’. We would like to be able to tune the weight of a replica inside HAProxy depending on its replication lag. This is what we will do in this post using HAProxy 1.5.

Agent …

I was fortunate to attend an Ops discussion about databases at the OpenStack Summit Atlanta this past May as one of the panelists. The discussion was about deadlock issues OpenStack operators see with Percona XtraDB Cluster (of course this is applicable to any Galera-based solution). I asked to describe what they are seeing, and as it turned out, nova and neutron uses the SELECT … FOR UPDATE SQL construct quite heavily. This is a topic I thought was worth writing about.

Write set replication in a nutshell (with oversimplification)

Any node is writable, and replication happens in write sets. A write …

ScaleArc recently hired Percona to perform various tests on its database traffic management product. This post is the outcome of the benchmarks carried out by me and ScaleArc co-founder and chief architect, Uday Sawant.

The goal of this benchmark was to identify ScaleArc’s overhead using a real-world application – the world’s most popular (according to wikipedia) content management system and blog engine: WordPress.

The tests also sought to identify the benefit of caching for this type of workload. The caching parameters represent more real-life circumstances than we applied in the sysbench performance tests – the goal here was not just to saturate the cache. For this reason, we created an artificial WordPress blog with generated data. …

ScaleArc recently hired Percona to perform various tests on its database traffic management product. This post is the outcome of the benchmarks carried out by Uday Sawant (ScaleArc) and myself. You can also download the report directly as a PDF here.

The goal of these benchmarks is to identify the potential overhead of the ScaleArc software itself and the potential benefits of caching. The benchmarks were carried out with the trunk version of sysbench. For this reason, we used a very small set of data, so the measurements will be fast, and it’s known that caching has huge benefits when the queries themselves are rather expensive. We decided that we would rather show that benefit with a real-world application, which is coming later is this series. And if you’re in the Silicon Valley area, be sure to join us this evening at the …

Many users are challenged with how to setup multi-master, multi-site MySQL clusters. How to do you go from a single database server to a scalable cluster? Or move from a brittle MySQL replication system to a transparent, manageable database cluster? In this joint webinar with Continuent, Percona examines how Continuent Tungsten addresses these problems. 

First, we discuss the read-write

I’m looking forward to next week’s MySQL webinar with Robert Hodges, CEO of Continuent. We’ll be speaking on the topic “Multi-Data Center MySQL with Continuent Tungsten.”

You’re not alone if you’ve been vexed when trying to assemble multi-master, multi-site MySQL clusters. Whether that was a move from a single database server to a scalable cluster, or from a brittle MySQL replication system to a transparent, manageable database cluster.

We’ve all been there at one point or another in our careers. So learn from our experience. In our joint webinar next week (Dec. 11), Robert and I will …

Memcache access for MySQL Cluster (or NDBCluster) provides faster access to the data because it avoids the SQL parsing overhead for simple lookups – which is a great feature. But what happens if I try to get multiple records via memcache API (multi-GET) and via SQL (SELECT with IN())? I’ve encountered this a few times now, so I decided to blog about it. I did a very simple benchmark with the following script:

#!/bin/bash
mysql_server="192.168.56.75"
mc_server="192.168.56.75"
mysql_cmd="mysql -h${mysql_server} --silent --silent"
mysql_schema="percona"
mysql_table="memcache_t"
mc_port=11211
mc_prefix="mt:"
function populate_data () {
  nrec=$1
  $mysql_cmd -e "delete from ${mysql_table};" $mysql_schema > /dev/null 2>&1
  for rec in `seq 1 $nrec`
  do
    $mysql_cmd -e "insert into ${mysql_table} values ($rec, repeat('a',10), 0, 0);" $mysql_schema > /dev/null 2>&1
  done
}
function mget_via_sql() {
  nrec=$1
  in_list=''
  for rec in …

MySQL can be deployed in several ways, and that means you can choose a tailor-made path that best meets your needs. With simple services or development systems, many people are using a single server with some backups configured, and then simply take the downtime when a restore is needed.

As the application evolves, additional requirements will appear like hot backups, online schema changes, replication based high availability (which has …

This blog post is part two of two. Like part one, published Wednesday, this is a cross-post from Groupon’s engineering blog. Thanks again to Kyle Oppenheim at Groupon. And one more reminder that I’ll be at the Percona Live MySQL Conference and Expo next week in Santa Clara, California so look for me there. You can checkout the sessions I’ll be leading here.

In my last post, I described a solution for keeping the caches of a MySQL standby server hot using MySQL slow logs with …