Archive for the ‘Databases’ Category

Trip report: LinuxCon North America, CentOS Dojo Paris, WebExpo Prague

I had quite a good time at LinuxCon North America/CloudOpen North America 2014, alongside my colleague Max Mether – between us, we gave a total of five talks. I noticed that this year there was a database heavy track – Morgan Tocker from Oracle’s MySQL Team had a few talks as did Martin MC Brown from Continuent. 

The interest in MariaDB stems from the fact that people are starting to just see it appear in CentOS 7, and its just everywhere (you can even get it from the latest Ubuntu LTS). This makes for giving interesting talks, since many are shipping MariaDB 5.5 as the default choice, but that’s something we released over 2 years ago; clearly there are many interesting new bits in MariaDB 10.0 that need attention!

Chicago is a fun place to be – the speaker gift was an architectural tour of Chicago by boat, probably one of the most useful gifts I’ve ever received (yes, I took plenty of photos!). The Linux Foundation team organised the event wonderfully as always, and I reckon the way the keynotes were setup with the booths in the same room was a clear winner – pity we didn’t have a booth there this year. 

Shortly afterwards, I headed to Paris for the CentOS Dojo. The room was full (some 50 attendees?), whom were mainly using CentOS and its clear that CentOS 7 comes with MariaDB so this was a talk to get people up to speed with what’s different with MySQL 5.5, what’s missing from MySQL 5.6, and when to look at MariaDB 10. We want to build CentOS 7 packages for the MariaDB repository (10.0 is already available with MariaDB 10.0.14), so watch MDEV-6433 in the meantime for the latest 5.5 builds.

Then there was WebExpo Prague, with over 1,400 attendees, held in various theatres around Prague. Lots of people here also using MariaDB, some rather interesting conversations on having a redis front-end, how we power many sites, etc. Its clear that there is a need for a meetup group here, there’s plenty of usage.

MySQLNoSQLCloud 2014 – Edition #3

Good morning buenos airesI’ve enjoyed visiting Buenos Aires once a year for the MySQLNoSQLCloud event, put together by the awesome people at Binlogic (in particular, their proprietor Santiago Lertora). It’s happening again in 2014, which by my count is the third edition, and there’s a twist: Buenos Aires on 13 & 14 November, and Cordoba on 17 November. It’s never been held in Cordoba before (like an annex event), so I think this could be extremely exciting.

If you’re looking to speak, send Santiago a note at events@binlogic.com (or leave a message here). I’ll put you in touch with him. If you’re looking to sponsor, you get attendees from all over Latin America.

Percona Live London Call for Presentations

Europe traditionally doesn’t have many MySQL-dedicated conferences, which is why I personally enjoy Percona Live London, now in its 2014 Edition. This year it happens November 3-4, and the call for presentations is still open – till August 17th.

DSCF1396The topic list is growing as the MySQL ecosystem matures: DevOps, cloud, security, case studies and what’s new are things you don’t often see. Tutorials are also welcome, of course.

Location-wise, London can’t be beat. And happening at Gloucester Road, you’re on the District/Circle/Picadilly lines to go to many fun places.

If you don’t want to present, do attend – registration is open. Early-bird (ending August 31st) conference & tutorials will set you back £425.00 and if you just want to attend the conference only, its £235.00 (VAT and fees excluded). A steal if you ask me!

See you there!

PERFORMANCE_SCHEMA disabled in MariaDB 10.0.12

Astute readers of the release notes for MariaDB 10.0.12 will notice that there is a line that reads: performance_schema is now disabled by default.

We didn’t come to this decision by accident. Recently at the SkySQL company meeting in Budapest, we did have some time to break out into our usual working teams to talk about our daily operations. Team MariaDB had a debate about PERFORMANCE_SCHEMA and how it was left on by mistake in 10.0 GA as there was a decision to turn it off. Personally, I don’t like introducing such changes in a GA release, and there was no archive of such a discussion, so the next best thing to do was to ask the MariaDB developers and users via a post to both maria-developers and maria-discuss (3 June 2014) and to ensure that a Jira ticket existed (MDEV-6249).

But first, let’s delve into a little background information for context of this discussion. Elena started investigating a query performance issue reported on IRC, and she found that with default settings the query performance dropped tremendously with PERFORMANCE_SCHEMA enabled. We had seen that the WebScaleSQL folk had disabled PERFORMANCE_SCHEMA and there was discussion on the mailing list about a loss in performance (“Our perf testing agrees with your assessment (we see about a 5%-6% perf hit when it’s included and on, and a 2%-3% hit when it’s included but off)”).

On the maria-developers and maria-discuss lists, no one complained about having such a change. Hence the decision to disable it by default now. The alternative to this in MariaDB that comes without performance overhead is user statistics. I read a comment somewhere that there is constant evolution of PERFORMANCE_SCHEMA but the user statistics haven’t changed in a while (since MariaDB 5.2), though reliable sources tell me that more work is being done on this. Do MariaDB users want to see evolution of user statistics?

So from a user standpoint, the best way to find out if PERFORMANCE_SCHEMA is ON or OFF is to run SHOW VARIABLES LIKE 'perf%';. On MariaDB 10.0.11, you will see that it is ON but on 10.0.12 you will see that it is OFF. If you are planning to enable it in a development environment, all you have to do is edit your my.cnf to have performance_schema=1 and restart your server to get to using it again.

It looks like the decision might have been the right one for the time being, looking at the recently resurfaced mysql#68514.

On-disk/block-level encryption for MariaDB

I don’t normally quote The Register, but I was clearing tabs and found this article: 350 DBAs stare blankly when reminded super-users can pinch data. It is an interesting read, telling you that there are many Snowden’s in waiting, possibly even in your organisation. 

From a MariaDB standpoint, you probably already read that column level encryption as well as block level encryption for some storage engines are likely to come to MariaBD 10.1 via a solution by Eperi. However with some recent breaking news, Google is also likely to do this – see this thread about MariaDB encryption on maria-discuss. 

Google has already developed on-disk/block-level encryption for InnoDB, Aria (for temporary tables), binary logs and temporary files. The code isn’t published yet, but will likely happen soon, so clear benefits of open source development principles. 

Elsewhere, if you’re trying to ensure good policies for users, don’t forget to start with the audit plugin and roles.

RHEL7 now with MariaDB

Congratulations to the entire team at Red Hat, for the release of Red Hat Enterprise Linux 7 (RHEL7). The release notes have something important, under Web Servers & Services:

MariaDB 5.5

MariaDB is the default implementation of MySQL in Red Hat Enterprise Linux 7. MariaDB is a community-developed fork of the MySQL database project, and provides a replacement for MySQL. MariaDB preserves API and ABI compatibility with MySQL and adds several new features; for example, a non-blocking client API library, the Aria and XtraDB storage engines with enhanced performance, better server status variables, and enhanced replication.

Detailed information about MariaDB can be found at https://mariadb.com/kb/en/what-is-mariadb-55/.

This is a huge improvement over MySQL 5.1.73 currently shipping in RHEL6. I’m really looking forward to welcome more MariaDB users. Remember if you are looking for information, find it at the Knowledge Base. If you’ve found a bug, report it at Jira (upstream) or Bugzilla (Red Hat). If you want to chat with friendly developers and users, hop on over to #maria on irc.freenode.net. And don’t forget we have some populated mailing lists: maria-discuss and maria-developers.


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