InnoDB Plugin 1.1 doesn’t add any recovery specific improvements on top of what we already have in Plugin 1.0.7. The details on the latter are available in this blog. Yet, when I tried to recover another big recovery dataset I created, I got the following results for total recovery time:

• Plugin 1.0.7: 46min 21s
• Plugin 1.1: 32min 41s

Plugin 1.1 recovery is 1.5 times faster. Why would that happen? The numerous concurrency improvements in Plugin 1.1 and MySQL 5.5 can’t really affect the recovery. The honor goes to Native Asynchronous IO on Linux. Let’s try without it:

• Plugin 1.1 with –innodb-use-native-aio=0: 49min 07s

which is about the same as 1.0.7 time. My numerous other recovery runs showed that the random fluctuations account for 2-3min of a …

Two examples of escaping data are the following:

• Before you insert a value into a SQL query, using for example mysqli::real_escape_string() or PDO::quote().
• Before you insert data into your output HTML, using htmlspecialchars().

The question I'd like to ask today is, when to do this? There are two possible moments:

1. Right when the data comes in. For SQL this used to be done with 'magic quotes' quite a bit in PHP-land. In general I don't see this happening a lot anymore for SQL. I do however see data encoded using htmlentities/htmlspecialchars before entering the database.
2. The other way to go about it, is to only escape …

The binary version for MySQL Cluster 6.3.33 has now been made available at http://www.mysql.com/downloads/cluster/6.3.html#downloads

A description of all of the changes (fixes) that have gone into MySQL Cluster 6.3.33 (compared to 6.3.32) can be found in the MySQL Cluster 6.3.33 ChangeLog .

Recently I was working with the output of pstack from a hung MySQL server and wanted to use Poor Man's Profiler in order to combine stack traces. Unfortunately, the awk magic expects the output from gdb's thread apply all bt output.

gdb output:

Thread 10 (Thread 0xa644db90 (LWP 26275)):
#0  0xb7f47410 in __kernel_vsyscall ()
#1  0xb7f33b1a in do_sigwait () from /lib/tls/i686/cmov/libpthread.so.0
#2  0xb7f33bbf in sigwait () from /lib/tls/i686/cmov/libpthread.so.0
#3  0x081cc4fc in signal_hand ()
#4  0xb7f2b4fb in start_thread () from /lib/tls/i686/cmov/libpthread.so.0
#5  0xb7d25e5e in clone () from /lib/tls/i686/cmov/libc.so.6

Thread 9 (Thread 0xa641cb90 (LWP 26273)):
#0  0xb7f47410 in __kernel_vsyscall ()
#1  0xb7d1e881 in select …

It really used to be easy to be a MySQL DBA.  Ten or so years ago, your bosses were amazed that this free database actually worked and users were happy to be able to store or retrieve data.  Then the database became a vital hub of your company's web presence, operations, and identity.  The last two years or so, your database and its data had to be faster, more robust, highly available, ACID compliant, sharded, clustered, replicated, normalized or de-normalized, distributed, and...

When you are importing large amounts of data from other sources LOAD DATA is a common method of inserting data into a table.
It is one of the old commands implemented in MySQL. As such it is very fast, and it has been optimized for both MyISAM and InnoDB.
All is well when you are loading data into a standalone server. All is almost well when you are using replication. LOAD DATA used to be a problem in old versions of MYSQL, prior to 4.1. With recent versions of MySQL, it is replicated correctly, and sometimes efficiently.
The trouble starts when the data file is big. The definition of big and the amount of trouble that you can get depends on many factors. That's why users may not realize that this problem exists, even with fairly large files, and then being hit by this disaster when the file is only a little larger than the previous …

We talked to Mark Matthews and Andy Bang, two core developers in the MySQL Enterprise Monitor team, to give us some insight into the new features in the latest MySQL Enterprise Release.

In my time at MySQL AB in the Community Relations possition (2004-2006) I wrote several articles on MySQL’s licensing for the MySQL web site. The core reason for having to explain anything was (and still is) the dual licensing of MySQL, in particular the client library. I left MySQL AB years ago, but people still ask me licensing questions. Below is an excerpt from one such question, and my response.

> Hi, Found a post on the mysql website from Arjen Lentz to do with the whole
> mysql licensing question.
> Do you know if the issue with, php scripts (that use a mysql database) issued
> under a proprietary license require you to have a commercial license for
> mysql, or will the issues be covered for the GPL version through the fact
> that the scripts run via php which in-turn connects to the GPL mysql server
> for which the FOSS exception applies.

Note: I am not a …

This is part four of an ongoing series about my experiences while writing the MySQL Admin Cookbook for Packt Publishing. All previous parts can be found under the mysql-admin-cookbook label.

This part will be about more software used in the process of writing the book. The last episode covered writing tools, file/version management and backups. What's up now is graphics programs, virtualization and PDF handling.

Outlining

For outlining and structuring thoughts I like mind-maps. I know they are not for everyone, but if you like them and do not want to spend a lot of money on …

I spent a little time yesterday doing some things with the “summary” tool from Aspersa. I added support for summarizing status and configuration of Adaptec and LSI MegaRAID controllers. I also figured out how to write a test suite for Bash scripts, so most major parts of the tool are fully tested now. I learned a lot more sed and awk this weekend.

There is really only one way to get status of Adaptec controllers (/usr/StorMan/arcconf), but the LSI controllers can be queried through multiple tools. I added support for MegaCli64, as long as it’s located in the usual place at /opt/MegaRAID/MegaCli/MegaCli64. I am looking for feedback and/or help on supporting other methods of getting status from the LSI controllers, such as megarc and omreport. If you can contribute sample output from these tools, please attach them as a file to a new issue report on the project’s issue …