May 20, 2013

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 [...]

Percona Server 5.5.10 (Release Candidate)

Percona Server release 5.5.10-20.1 is now available for download. This is a release candidate for the Percona Server 5.5 series. In addition to MySQL 5.5.10 now being the base version, here are the changes that have been made since Percona Server beta release 5.5.8-20.0:

What is innodb_support_xa?

A common misunderstanding about innodb_support_xa is that it enables user-initiated XA transactions, that is, transactions that are prepared and then committed on multiple systems, with an external transaction coordinator. This is actually not precisely what this option is for. It enables two-phase commit in InnoDB (prepare, then commit). This is necessary not only for user-initiated [...]

MySQL 5.5.8 – in search of stability

A couple of days ago, Dimitri published a blog post, Analyzing Percona’s TPCC-like Workload on MySQL 5.5, which was  a response to my post, MySQL 5.5.8 and Percona Server: being adaptive. I will refer to Dimitri’s article as article [1]. As always, Dimitri has provided a very detailed and thoughtful article, and I strongly recommend reading if [...]

Percona Server 5.1.52-12.3

Percona Server version 5.1.52-12.3 is now available for download. The main purpose of this release is to update the current Percona release candidate to the latest version of MySQL 5.1. The release also includes the HandlerSocket plugin, which provides NoSQL features in Percona Server. Functionality Added or Changed Percona Server 5.1.52-12.3 is now based on [...]

Storing MySQL Binary logs on NFS Volume

There is a lot of discussions whenever running MySQL storing data on NFS is a good idea. There is a lot of things for and against this and this post is not about them. The fact is number of people run their databases on NetApp and other forms of NFS storage and this post is [...]

Blob Storage in Innodb

I’m running in this misconception second time in a week or so, so it is time to blog about it. How blobs are stored in Innodb ? This depends on 3 factors. Blob size; Full row size and Innodb row format. But before we look into how BLOBs are really stored lets see what misconception [...]

5.0.77 / 5.0.82 -build16 Percona binaries

Dear community, We are pleased to announce the build16 of MySQL server® with Percona patches. Since the build13 there was a couple of customer specific releases, which explains cutover in numbering and a pause between the builds. Also we prepared build for both 5.0.77 and 5.0.82 versions. Since that time new patches were added: profiling_slow.patch [...]

XtraDB storage engine release 1.0.2-3 (Spring edition) codename Sapporo

Today we announce release 1.0.2-3 of our XtraDB storage engine. Here is a list of enhancements: Move to MySQL 5.1.31 Scalability fix — ability to use several rollback segments Increasing the number of rseg may be helpful for CPU scale of write-intentional workloads. See benchmark results. Scalability fix — replaced page_hash mutex to page_hash read-write [...]

Pretending to fix broken group commit

The problem with broken group commit was discusses many times, bug report was reported 3.5 years ago and still not fixed in MySQL 5.0/5.1 (and most likely will not be in MySQL 5.1). Although the rough truth is this bug is very hard (if possible) to fix properly. In short words if you enable replication (log-bin) on server [...]