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Maatkit contains essential command-line utilities for MySQL, such as a table checksum tool and query profiler. It provides missing features such as checking slaves for data consistency, with emphasis on quality and scriptability.

This release contains major bug fixes and new features. Some of the changes are not backwards-compatible. It also contains new tools to help you discover replication slaves and move them around the replication hierarchy.

Changelog for mk-archiver:

2008-03-16: version 1.0.8

   * Added --setvars option (bug #1904689, bug #1911371).
   * Added --charset option (bug #1877548).
   * Changed short form of --analyze to -Z to avoid conflict with --charset.

Changelog for mk-deadlock-logger:

2008-03-16: version 1.0.9

   * Added --setvars option (bug #1904689, bug #1911371).
   * Added 'A' part to DSNs (bug #1877548).

Changelog for …

I wrote a User-Defined Function that implements the FNV (Fowler-Voll-No) hash function for MySQL. I’m not the first person to do this — in fact, I was inspired by the Google patches for MySQL. But my implementation is a little bit different from most, in a very important way that leads directly to much higher performance, especially suited for the Maatkit tools.

A bit of background: FNV hashing is a very fast hash algorithm that operates in fixed memory. It is widely used in lots of important areas in computer science. My implementation requires absolutely no malloc() calls, which is a darn good thing because I am not to be trusted with malloc(), having spent too …

I saw a post by Baron mentioning that his tool maatkit is best for handling situations where a master-master replication setup has got out of sync.

If you think Baron was blowing his own trumpet he has good reason to. I have used his mk-archiver tool as part of the Maatkit to make the problem of archiving and purging data much easier. This was much easier than rolling my own solution.

Anyhow. I

Suppose you have a master-master replication setup, and you know one of the tables has the wrong data. How do you re-sync it with the other server?

Warning: don’t just use any tool for this job! You may destroy your good copy of the data.

If your table is large, you’ll probably want to use a tool that can smartly find the differences in a very large dataset, and fix only the rows that need to be fixed. There are several tools that are either able to do this, or claim to be able to do this. However, most of them are not replication-aware, and are likely to either break replication or destroy data.

To see why this is, let’s look at a typical scenario. You have server1 and server2 set up as co-masters. On server1, your copy of sakila.film has correct data. On server2, somehow you are missing a row in that table. A hypothetical sync tool will compare the two copies of the data and find …

Download Maatkit

This release contains minor bug fixes and new features. Besides the little bug fixes, there's a fun new feature in mk-heartbeat: it can auto-discover slaves recursively, and show the replication delay on all of them, to wit:

baron@keywest ~ $ mk-heartbeat --check --host master -D rkdb --recurse 10
master 0
slave1 1
slave2 1
slave3 4

(Not actual results. Your mileage may vary. Closed course, professional driver. Do not attempt).

Nothing else in this release is very exciting. I just wanted to get the bug fixes out there.

This release contains bug fixes and new features. It also contains a new tool: my implementation of Paul Tuckfield's relay log pipelining idea. I have had quite a few responses to that blog post, and requests for the code. So I'm releasing it as part of Maatkit.

This release contains bug fixes and new features. Click through to the full article for the details. I'll also write more about the changes in a separate article.

My posts lately have been mostly progress reports and release notices. That's because we're in the home stretch on the book, and I don't have much spare time. However, a lot has also been changing with Maatkit, and I wanted to take some time to write about it properly.

This release contains bug fixes and new features. The biggest new feature, in my opinion, is a new sync algorithm for mk-table-sync. Now you can sync any table with an index more efficiently than previously. This is the return of the speed I promised earlier. (Though I haven't yet benchmarked it; I am very short on time these days. Your benchmarks and other contributions are welcome).

I'm finally feeling like the table sync tool is getting in good shape!

Changelog etc is in the full article.

The “sla” in mysqlsla stands for “statement log analyzer”. This does a much better job than mysqldumpslow of analyzing your slow query log. In fact, you can sort by many different parameters — by sheer number of times the query shows up in the slow query log, by the total or average query [...]