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Anyone want to help build RPMs of Maatkit?
Dear LazyWeb, I want to use my Ubuntu laptop (on amd64 BTW) to build an RPM of Maatkit that will work on all RPM-based distros. Is it possible? Or are there enough differences between the RPM-based distros that I can’t do it? Mind you, the finished RPM ought to just have some man pages and Perl scripts, so I don’t think it will be platform- or distro-specific. But I am just not an expert on it.
The second question is, what do I need to put into my Makefile to do this? My ‘make all’ currently builds a .zip, a .tar.gz, and a .deb package — what needs to change to make that include .rpm?
Someone who is willing to help create .spec files, etc, etc will be immediately given commit rights to Maatkit’s SVN repository!
Debian, packaging, RPMPercona wants to hire a Maatkit developer
Percona is looking to hire someone to develop Maatkit, among other things.
If I weren’t having so much fun being the consulting team lead, I’d be doing it myself. (In fact, I’m still hacking on it a lot. Got some pretty fun stuff done this weekend.) I don’t know what the rest of the world thinks, but I think Maatkit is a damn enjoyable project to work on. Hopefully someone else will have the same kind of mindset and want to get paid for it, unlike poor working-on-the-weekends me.
I’m not stepping away from the project. It’s just grown a lot, and there is room and money to grow it much more. This is actually the best compliment to the project: that it is worth hiring someone to keep improving it. Lots of people are using it, and there’s a lot of stealth-mode stuff I/we want to do with it too.
On a related note, who wants me to order another batch of Maatkit t-shirts? I’ve gotten quite a few questions about it.
No Tags5.0 journal: various issues, replication prefetching, our branch
First of all, I have to apologize about some of my previous remark on 5.0 performance. I passed ‘-g’ CFLAGS to my build, and that replaced default ‘-O2′. Compiling MySQL without -O2 or -O3 makes it slower. Apparently, much slower.
Few migration notes - once I loaded the schema with character set set to binary (because we treat it as such), all VARCHAR fields were converted to VARBINARY, what I expected, but more annoying was CHAR converted to BINARY - which pads data with \0 bytes. Solution was converting everything into VARBINARY - as actually it doesn’t have much overhead. TRIM('\0' FROM field) eventually helped too.
The other problem I hit was paramy operation issue. One table definition failed, so paramy exited immediately - though it had few more queries remaining in the queue - so most recent data from some table was not inserted. The cheap workaround was adding -f option, which just ignores errors. Had to reload all data though…
I had real fun experimenting with auto-inc locking. As it was major problem for initial paramy tests, I hacked InnoDB not to acquire auto-inc table-level lock (that was just commenting out few lines in ha_innodb.cc). After that change CPU use went to >300% instead of ~100% - so I felt nearly like I’ve done the good thing. Interesting though - profile showed that quite a lot of CPU time was spent in synchronization - mutexes and such - so I hit SMP contention at just 4 cores. Still, the import was faster (or at least the perception), and I already have in mind few cheap tricks to make it faster (like disabling mempool). The easiest way to make it manageable is simply provide a global variable for auto-inc behavior, though elegant solutions would attach to ‘ALTER TABLE … ENABLE KEYS’ or something similar.
Once loaded, catching up on replication was another task worth few experiments. As the data image was already quite a few days old, I had at least few hours to try to speed up replication. Apparently, Jay Janssen’s prefetcher has disappeared from the internets, so the only one left was maatkit’s mk-slave-prefetch. It rewrites UPDATEs into simple SELECTs, but executes them just on single thread, so the prefetcher was just few seconds ahead of SQL thread - and speedup was less than 50%. I made a quick hack that parallelized the task, and it managed to double replication speed.
Still, there’re few problems with the concept - it preheats just one index, used for lookup, and doesn’t work on secondary indexes. Actually analyzing the query, identifying what and where changes, and sending a select with UNIONs, preheating every index affected by write query could be more efficient. Additionally it would make adaptive hash or insert buffers useless - as all buffer pool pages required would be already in memory - thus leading to less spots of mutex contention.
We also managed to hit few optimizer bugs too, related to casting changes in 5.0. Back in 4.0 it was safe to pass all constants as strings, but 5.0 started making poor solutions then (like filesorting, instead of using existing ref lookup index, etc). I will have to review why this happens, does it make sense, and if not - file a bug. For now, we have some workarounds, and don’t seem to be bitten too much by the behavior.
Anyway, in the end I directed half of this site’s core database off-peak load to this machine, and it was still keeping up with replication at ~8000 queries per second. The odd thing yet is that though 5.0 eats ~30% more CPU, it shows up on profiling as faster-responding box. I guess we’re just doing something wrong.
I’ve published our MySQL branch at launchpad. Do note, release process is somewhat ad-hoc (or non-existing), and engineer doing it is clueless newbie. :)
I had plans to do some more scalability tests today, but apparently the server available is just two-core machine, so there’s nothing much I can do on it. I guess another option is grabbing some 8-core application server and play with it. :)
Maatkit version 1972 released
Before I tell you what’s new, let me tell you how cool I think it would be if Maatkit were voted Sourceforge.net project of the year. Just something to think about :-) I suggest the “Best Tool or Utility for SysAdmins” category. You can actually click the Back button and nominate it for several categories. Not that anyone would do that, of course.
Also, if anyone wants to jump in and help out with bug fixes and new features, please, by all means. Maatkit is a true open-source project as well as being Free Software. If you can follow coding conventions and understand Perl, I’m a very benevolent dictator and would gladly grant commit rights. As it turns out, since I’ve joined Percona I’m interested in a whole different set of things, and a lot of the itches I was scratching with Maatkit before are no longer mine to scratch. Some of my direct motivation to improve Maatkit is therefore reduced. (To those of you who have sent me gifts from my wishlist, thank you, I really appreciate it. My latest is the score to Crimson Tide, which is just fastastic.)
This release is a bugfix and maintenance release. Many of the changes are minor tweaks to shared code. I’ve also partially moved to a new documentation system that will ensure the embedded documentation is authoritative and accurate.
Here’s the change log:
Changelog for mk-archiver: 2008-06-02: version 1.0.9 * Updated common code. Changelog for mk-deadlock-logger: 2008-06-02: version 1.0.10 * Generate command-line options from POD. Changelog for mk-duplicate-key-checker: 2008-06-02: version 1.1.6 * Updated common code. Changelog for mk-find: 2008-06-02: version 0.9.11 * Updated common code. Changelog for mk-heartbeat: 2008-06-02: version 1.0.9 * Get command-line options from POD. * --check output contained leading whitespace which broke Cacti. Changelog for mk-parallel-dump: 2008-06-02: version 1.0.8 * System commands did not use double quotes on Windows (bug #1949922). * Added --stopslave to run STOP SLAVE during the dump (bug #1923627). * --ignoreengine worked only when --tab was specified (bug #1851461). Changelog for mk-parallel-restore: 2008-06-02: version 1.0.7 * .trg files were sometimes rejected from loading. * Command-line options are generated from the POD. Changelog for mk-query-profiler: 2008-06-02: version 1.1.10 * Generate command-line options from POD. Changelog for mk-show-grants: 2008-06-02: version 1.0.10 * Create command-line options from POD. Changelog for mk-slave-delay: 2008-06-02: version 1.0.7 * Updated the documentation to use POD. * The slave could wait forever if the I/O thread was stopped. * The slave could wait forever on the master's last event (bug #1959496). Changelog for mk-slave-find: 2008-06-02: version 1.0.1 * Updated common code. Changelog for mk-slave-move: 2008-06-02: version 0.9.1 * Command-line parsing was removing an expected DSN (bug #1960142). * The slave was not stopped before CHANGE MASTER TO (bug #1960142). * DSNs without a port caused a crash (bug #1960142). * Converted to use POD for command-line options. Changelog for mk-slave-prefetch: 2008-06-02: version 1.0.2 * Add the --progress option. * Add more error reporting and the --errors option. * Abstract USE queries when fingerprinting them. * mysqlbinlog errors were not detected. * Handle queries of the form INSERT ... VALUE(). * Strip comments from queries when normalizing them. Changelog for mk-slave-restart: 2008-06-02: version 1.0.7 * Updated common code. Changelog for mk-table-checksum: 2008-06-02: version 1.1.27 * Update documentation, generate command-line options from POD. * Added --trim to compare pre-5.0 and 5.0+ VARCHAR values consistently. Changelog for mk-table-sync: 2008-06-02: version 1.0.7 * Added NO_AUTO_VALUE_ON_ZERO to @@SQL_MODE (bug #1919897). * Added --trim to compare pre-5.0 and 5.0+ VARCHAR values consistently. Changelog for mk-visual-explain: 2008-06-02: version 1.0.8 * Updated common code.Community Choice Awards, mysql, Sourceforge.net
MySQL Conference and Expo 2008, Day Three
Here’s a rundown of Thursday (day 3) of the MySQL Conference and Expo. This day’s sessions were much more interesting to me than Wednesday’s, and in fact I wanted to go to several of them in a single time slot a couple of times.
Inside the PBXT Storage Engine
This session was, as it sounds, a look at the internals of PBXT, a transactional storage engine for MySQL that has some interesting design techniques. I had been looking forward to this session for a while, and Paul McCullagh’s nice explanations with clear diagrams were a welcome aid to understanding how PBXT works. Unlike some of the other storage engines, PBXT is being developed in full daylight, with an emphasis on community involvement and input. (Indeed, I may be contributing to it myself, in order to make its monitoring and tuning capabilities second to none).
PBXT has not only a unique design, but a clear vision for differentiating itself from other transactional storage engines. It’s not trying to clone any particular engine; Paul and friends are planning to add some capabilities that will really set it apart from other engines, including high-availability features and blob streaming.
I left this session with a much better understanding of how PBXT balances various demands to satisfy all sorts of different workload characteristics, how it writes data, how it achieves transactional durability, and so on. I think these capabilities, and its performance, can really be assessed only in the real world (of course), but in principle it sounds good. I love knowing how things work!
There were about 30 people in the talk. I wish there had been more, because I think PBXT is going to be an important part of the open ecosystem going forward. However, I feel pretty confident people will take more notice if it starts to get used in the real world. Someone had a video camera there, so you might check out the video when it’s available. Paul’s explanations are really good.
Helping InnoDB Scale on Servers with Many CPU Cores and Disks
This session was Mark Callaghan’s chance to unveil the work he and others have been doing on InnoDB’s scalability issues, which mostly revolve around mutex contention. Mark’s team has completely solved the problems on their workload and benchmarks. In fact, after the changes, InnoDB exhibited significantly better performance even than MyISAM, which began to be limited by the single mutex that synchronizes access to its key cache. (Yes, in fact MyISAM has scalability problems too).
Google’s workload for MySQL, in case you’re wondering, is pretty traditional (i.e. not web-like; more like an “enterprise” application). Heavily I/O-bound, 24/7 critical systems, and so on.
Mark also wore several community t-shirts at various points in the talk, including one of my Maatkit t-shirts. Mark said Maatkit would be perfect if only it were written in Python (Google’s preferred scripting language). Alas, Mark, it’ll stay in Perl. But thanks for the nice compliment anyway.
The room was packed full.
Scaling Heavy Concurrent Writes In Real Time
Dathan Pattishall, formerly the lead architect at Flickr, explained his techniques for scaling Flickr’s write capacity. He talked about how he’d worked to reduce primary key sizes, queued writes for batching, separated different types of data into different types of tables, and more. Dathan has never been afraid to do what he thinks is a good idea, even if it flies in the face of “best practices,” so I was happy to finally hear him talk.
By the way, Dathan pointed out that distributed locking with memcached and add() isn’t a silver bullet. It works ok until memcached evicts your lock due to the LRU policy. He uses MySQL’s built-in GET_LOCK() function for locking.
Dathan’s blog is a good source of information about his sometimes unorthodox approaches to database design.
The Power of Lucene
This was the only one of Frank (Farhan) Mashraqi’s talks I got to attend. This was pretty technical: how Lucene works, how to configure and install it, how to index documents, how to execute searches. If you were wondering how much work and complexity it would be to install and use Lucene, this talk would have been good for you to attend; I’ve never used it myself, but I’m pretty sure Frank covered everything you need to know.
Dathan Pattishall, Farhan Mashraqi, GET LOCK, innodb, Lucene, maatkit, Mark Callaghan, memcached, myisam, mysqluc2008, Paul McCullagh, pbxtMySQL Conference and Expo 2008, Day Two
Day two of the conference was a little disappointing, as far as sessions went. There were several time blocks where I simply wasn’t interested in any of the sessions. Instead, I went to the expo hall and tried to pry straight answers out of sly salespeople. Here’s what I attended.
Paying It Forward: Harnessing the MySQL Contributory Resources
This was a talk focused on how MySQL has made it possible for community members to contribute to MySQL. There was quite a bit of talk about IRC channels, mailing lists, and the like. However, the talk gave short shrift to how MySQL plans to become truly open source (in terms of its development model, not its license). I think there was basically nothing to talk about there. I had a good conversation about some of my concerns with the speaker and some others from MySQL right afterwards.
There was basically nobody there — I didn’t count, but I’d say maybe 10 or 12 people. I think this is a telling sign.
Architecture of Maria: A New Storage Engine with a Transactional Design
I was interested in this talk because I’m interested in the tension between Falcon and Maria (and between Falcon and everything, for that matter) but I left and went to the expo hall again after a bit. The talk was good but I’d already seen and/or read it, and the question-and-answer component wasn’t enough to keep me there.
The MySQL Query Cache
This was the second session I gave at the conference, and again it was standing-room-only, with nearly 300 attendees according to the person who was watching the door. The questions were frequent and added a lot to the discussion. Slides will be on the conference website when they post them.
Grazr: Lessons Learned Building a Web 2.0 Application Using MySQL
I was keenly interested in this talk because a) I am a big fan of Patrick Galbraith’s work with many different projects, and b) I had heard a lot about Grazr but didn’t know much about it. However, I missed most of the talk. About ten minutes into it, I got a call I couldn’t refuse: my wife!
However, I did sneak back into the room for the last bit too. And I gave Grazr a try. Unfortunately, I got really confused by it; I tried a bunch of different ways to import my Google Reader’s OPML. I got that to work, but then I couldn’t figure out how to read the feeds in the OPML via Grazr. Then I think I figured that out (I’m not sure) but it didn’t strike me as a very handy way to read my feeds. I’ll try taking another look at it later if I get time. (I’m all ears if there’s a better way to read feeds).
Extending MySQL
This one was mostly for fun. I knew a lot about UDFs already (I’ve created some) and I knew about the pluggable storage engine API. But I didn’t know about pluggable event daemons. Holy cow, what a great way to shoot yourself (or your server) in the foot! All the power of an atomic bomb, with all the safety of SPF 5 sunblock in a nuclear attack. Or something like that. But darn, it sure is nifty. Brian is a great speaker too — very lively.
You know, there’s another way to extend MySQL that most people don’t seem to know about, which Brian didn’t mention. That is procedures (not stored procedures). They are sort of like a post-filter for a result set, and like UDFs they’ve been around forever. I have never heard of anyone writing their own, but there’s an example in the server itself: PROCEDURE ANALYSE.
Expo hall
I went to the expo hall to meet and greet many of the companies that Percona (my employer) is already working with (doing independent benchmarks, performance verification, analysis etc) or will be in the future. I also wanted to grill some of the vendors on their technology. Usually I find them very cagey; they claim X times faster this-or-that, but won’t tell you how, and won’t tell you what their systems don’t do well. I don’t understand why they take this approach; you can’t hide your system’s strong and weak spots. There is no security through obscurity, and shrewd independent observers are going to get to the bottom of it with or without your permission.
So, for instance, I was talking with Tokutek, who claimed to be a drop-in replacement for InnoDB with 200x better performance and apparently no downsides. However, on closer questioning, I did get him to admit that the system has table-level locking. Thus it won’t give any concurrency, so saying it’s a drop-in InnoDB replacement is questionable. And the comparison against InnoDB seemed contrived to create a worst-case situation with bad tuning and a workload so it would perform terribly. An honest comparison tunes both systems to their highest performance and measures them; you can’t tune one system as badly as possible and compare it to the other’s best-case performance. I pressed on further and asked about range scans in some specific cases (they claim they’re great at range queries, and equal to InnoDB on everything else). At last they admitted they can’t perform well on some very common queries such as real-life queries InnoDB performs very well on for me. They said these are “point queries” but that’s not true; you can design indexes to support many different ways to range-query a table in InnoDB and get great performance. So it sounds to me like Tokutek’s storage format is extremely narrowly focused, and there is indeed a trade-off. I will be interested to see how their technology develops, though. It’s not done yet.
In general
There are a lot of Maatkit t-shirts walking around, which makes me happy. If I’d printed 200 of them, I probably could have given them all away. I was wearing a PostgreSQL t-shirt myself. Proudly, I might add. I’m not the only person here who’s interested in PostgreSQL. This morning I met a person from EnterpriseDB.
Yesterday was a bit slow in terms of interesting sessions, but there was a lot going on in the hallways, the expo hall, the meetings over lunch, and so on.
Brian Aker, EnterpriseDB, Falcon, Grazr, maatkit, Maria, mysqluc2008, Patrick Galbraith, Percona, query cache, Tokutek
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MySQL Community Member of the Year
MySQL just gave me an award at this morning’s keynote, along with Sheeri Kritzer Cabral (for the second year in a row!) and Diego Medina, for my code contributions to the MySQL community, specifically Maatkit, which makes it easier to make MySQL reliable, fast, and robust. It’s an honor to be recognized. And while I could leave it at that, I’d like to say a word or two more.
The economy, community, and ecosystem that’s building around Free Software can often be very rewarding financially. This is a great motivation; being rewarded for your efforts is one of the chief virtues of a culture of entrepreneurship, along with the idea that to try and fail is just as noble as to succeed. But I find that isn’t enough. If I were only rewarded financially and with recognitions such as this morning’s, I would quickly become bankrupt at a deeper level. I would become focused on external measures of success, such as accolade and wealth.
That’s why it’s so important to be of service to others and to work for the good of all. This is one of the strongest counterbalances for me. It helps keep me humbler and more open.
In the end, Free Software is all about this. It reminds me always that we are all interconnected, and that to work for your highest good is to work for my own.
I believe we all need at least these three things deeply:
- To chart your own course in life.
- To be of service to others.
- To make the most of what you have.
Does proprietary software offer you the chance to do this? No, it does not. It makes you beholden and dependent, not free. To pursue these three goals to their maximum extent you need freedom. “Make the most of what you have” doesn’t imply that you have to just accept what’s given to you; you can also take some time to see what your choices are, and choose something that gives you more freedom if possible. That’s what I did years ago when I moved away from using proprietary software.
I hope you’ll give this a try yourself: contribute what you build internally in your company, and put in the extra effort to make it really high quality and useful for everyone. This is how Maatkit started. Don’t wait for others to make it happen: chart your own course.
This morning’s award is most important to me because it reinforces that I’m serving others well.
Diego Medina, Sheeri Kritzer CabralMaatkit t-shirts are here
I’m at the MySQL Conference and the t-shirts I created for Maatkit have arrived. Come get yours! They are high-quality, attractive shirts you’ll be proud to wear, and they are a nice rich wine-red color.
Harrison Fisk (co-author of MySQL Clustering) got the first one, because he told me that he recommends Maatkit to MySQL Support customers about twice a week. I made sure to save one for Jay Pipes too, because his luggage got lost so he has nothing to wear. Unfortunately, I didn’t make any Maatkit underwear, sorry Jay. Now I know what to do for next year…
I’ve already given out a whole bunch of them, and at this rate all 50 of them might not last the day!
Harrison Fisk, Jay Pipes, maatkit, mysqlI have joined Percona
Effective April 1, I will join Percona full-time as a consultant. I'll be helping people build high-performance applications with MySQL, but I'll also be continuing to develop and improve tools such as Maatkit.
This career change has been a long time in progress. I'm really looking forward to it, but at the same time it's hard to leave my current employer, The Rimm-Kaufman Group (RKG). Working with them has been the best job I've ever had. But ultimately, my dream job is to help as many people as I can, and consulting will be a better way to do that.
At a time like this, I like to reflect on the trail that has led here. It's a good opportunity to realize how fortunate I really am and fill up my gratitude tank. So I'd like to thank everyone who has helped me reach this point. All the people who have encouraged me, sponsored me, suggested new options... all kinds of help. A special thanks to my wife, Alan Rimm-Kaufman and all my colleagues at RKG, the many fine people at MySQL, and the MySQL community as a whole. My deep gratitude to all of you. I look forward to working with you even more in the future.
Maatkit version 1877 released
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 mk-duplicate-key-checker: 2008-03-16: version 1.1.5 * Added --setvars option (bug #1904689, bug #1911371). * Added --charset option (bug #1877548). Changelog for mk-find: 2008-03-16: version 0.9.10 * Added --setvars option (bug #1904689, bug #1911371). * Added --charset option (bug #1877548). Changelog for mk-heartbeat: 2008-03-16: version 1.0.8 * Added --setvars option (bug #1904689, bug #1911371). * Added --charset option (bug #1877548). Changelog for mk-parallel-dump: 2008-03-16: version 1.0.7 * Added --setvars option (bug #1904689, bug #1911371). * Added --charset option (bug #1877548). * A global database connection was re-used by children, causing a hang. Changelog for mk-parallel-restore: 2008-03-16: version 1.0.6 * Added --setvars option (bug #1904689, bug #1911371). * Changed --charset to be compatible with other tools (bug #1877548). Changelog for mk-query-profiler: 2008-03-16: version 1.1.9 * Added --setvars option (bug #1904689, bug #1911371). * Added --charset option (bug #1877548). Changelog for mk-show-grants: 2008-03-16: version 1.0.9 * Added --setvars option (bug #1904689, bug #1911371). * Added --charset option (bug #1877548). Changelog for mk-slave-delay: 2008-03-16: version 1.0.6 * Added --setvars option (bug #1904689, bug #1911371). * Added 'A' part to DSNs (bug #1877548). Changelog for mk-slave-find: 2008-03-16: version 1.0.0 * Initial release. Changelog for mk-slave-move: 2008-03-16: version 0.9.0 * Initial release. Changelog for mk-slave-prefetch: 2008-03-16: version 1.0.1 * Added --setvars option (bug #1904689, bug #1911371). * Added --charset option (bug #1877548). Changelog for mk-slave-restart: 2008-03-16: version 1.0.6 * Added --setvars option (bug #1904689, bug #1911371). * Added --charset option (bug #1877548). * Added logic to repair tables, and rewrote a lot of code. * Added --always option, disabled by default. Not backwards compatible. * --daemonize did not work. * --quiet caused an undefined variable error. Changelog for mk-table-checksum: 2008-03-16: version 1.1.26 * Added --setvars option (bug #1904689, bug #1911371). * Added 'A' part to DSNs (bug #1877548). * Added --unique option to mk-checksum-filter. * The exit status from mk-checksum-filter was always 0. * mk-table-checksum now prefers to discover slaves via SHOW PROCESSLIST. Changelog for mk-table-sync: 2008-03-16: version 1.0.6 * --chunksize was not being converted to rowcount (bug #1902341). * Added --setvars option (bug #1904689, bug #1911371). * Deprecated the --utf8 option in favor of the A part in DSNs. * Mixed-case identifiers caused case-sensitivity issues (bug #1910276). * Prefer SHOW PROCESSLIST when looking for slaves of a server. Changelog for mk-visual-explain: 2008-03-16: version 1.0.7 * Added --setvars option (bug #1904689, bug #1911371). * Added --charset option (bug #1877548).
How to sync tables in master-master MySQL replication
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.
Maatkit version 1753 released
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.
Maatkit version 1709 released
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.
What is new in Maatkit
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.
Maatkit version 1579 released
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.
Maatkit version 1508 released
This release fixes a few bugs, adds minor features, and adds some debugging support to shared code. I'm working on the Nibble sync algorithm for mk-table-sync, and someone has found a few more bugs with mk-parallel-dump, but those might take me a while to complete.