These days, we seem to be getting a lot of inquiries from new or would-be DRBD adopters, especially MySQL and PostgreSQL DBAs wanting to add high availability to their master database servers. And these, unsurprisingly, turn out to be two of their most popular questions:

How will using DRBD affect my write performance?

… and …

What are DRBD’s most important tunables with regard to write performance?

Let’s take a look at both of these issues. Ready? Let’s go.

Basically, there’s usually one important potential bottleneck in any DRBD “Protocol C” (synchronous replication) setup, and it’s not the network connection. With ubiquitous Gigabit Ethernet links available to be dedicated for DRBD replication, network latency and throughput become negligable variables. The …

I work in IT for 2 reasons, firstly it pays well but secondly and most importantly it's fun. When I look back on jobs I had before I started working in IT, while it was never a problem getting up in the morning and the social aspects were great I would never have said that the job it self was fun.

It's been sometime since I last updated the blog, 6 moths or so and almost a year since I did on anything like a regular basis, the main reason as I have mentioned in the past is that if you have nothing to say then why bother saying it. Therefore I doubt anybody is listening any longer, but I suppose that's not really an issue.

I have been prompted to write because I have been doing some work on a site in MySQL, in the day job I use Oracle (but do some admin on MySQL sites from time to time) so I no longer have the experiences to blog about. But I recently needed to upgrade a family members web site which required some MySQL …

Look! I'm blogging!
I'm inspired to add a little twist to this. Lets give this 'blog-y' thing a try before I slink back into obscurity.

So, I'm limiting this list to my top five wishes for MySQL, that I have an ability or idea on how to influence.

1) Logical separation of connections from threads

If you do not have full control of the queries hitting your DB, you open a new world by allowing logic inbetween your connections and the query engine.

• First, this means that the connections != threads running, and an immediate benefit would be making queries over a limit 'queue' in some way. perlbal + apache MaxClients really smooths over throughput, why can't MySQL do the same?
  
• So many cool tricks! Want to rate limit by IO/s? Imagine having control of a query as it traverses …

While at the Linux Foundation meeting last week I spent some time
talking to Allison Randall. I told her about my recent vacation and
how I ditched my MySQL email during that period. Its the first time I
have ever done this, just shut off an email pipe. I went as far as
deleting my MySQL account from Mail.app so that I wouldn't be tempted
to even look at it.

We were talking for a bit about our experiences with receiving lots
of email and how to handle it. I noticed from our conversation that
we had both found coping skills that resulted in both of us treating
email as a very lossy environment.

I don't respond to all of my email. In fact, I don't even read CC'ed
email except for maybe once a week (and sometimes not even that). If
you want my attention then I assume you put me on the To: line, since
you are actually thinking of me. This …

MySQL AB today announced that the high-availability MySQL Cluster database conducts critical Web-centric, real-time data processing for Zillow.com, one of the Web's most-visited real estate sites, with 4.2 million unique visitors in May 2007.

Alfresco has a seminar next week in Munich, on Tuesday 26.6.2007 17:00-20:00 at the Hotel Excelsior close to Stachus. I’ll be talking about MySQL’s relationship to its communities.

I’m looking forward to meeting our joint users, and learning more about Alfresco Enterprise Content Management — including the case study from the Swiss Federal Court.

So you ran into some basic limitations with MyISAM when your site got busier. Even single row updates would lock the whole table and slow things down to a crawl. Then you updated to InnoDB to get the benefit of row-level locking, but now the site is even slower than before. What gives? Well, we [...]

I’ve been able to steal some more time to work on my script following My ?hourly? MySQL monitor script Version 0.03 almost a month ago.

The purpose of this script is simple. Create an hourly ‘cron’ job that records and monitors information against the OS and MySQL Server. This is most helpful when environments simply don’t have any monitoring in place. I’ve found it very productive when running a benchmark on site to simply enable for an hour. An amount of analysis is required, but I at least have a baseline of data collection. That is the first goal.

So hourly.0.05.tar.gz is taking some shape, and has the following new features:

• Provide configurable flag to enable/disable OS and MySQL tests
• Added MYSQL_SID support, allowing for running MySQL tests against …

Or, Why is My Transaction So Big? My team and I still use old-style rollback segments for one of my client’s 10g production databases. We just never found the need to switch to automatic undo management. There are a number of 1GB rollback segments. They are that size because they need to be able to support [...]

somewhere in these 1.6GB of debug log files and signal traces… somewhere… really.