We had the first MariaDB Berlin Meetup on Tuesday 12.04.2016 at the Wikimedia Berlin offices at 7pm. More or less there were over 54 people that attended the event, a mix of MariaDB Corporation employees and community members. We competed with the entertainment at the AWS Summit Berlin which was apparently about 400m away! Food and drink were enjoyed by all, and most importantly there were many, many lightning talks (minimum 5 minutes, maximum 10 minutes – most were about 6-7 minutes long).

The bonus of all of this? Lots and lots of slides for you to see. Grab them from the Google Drive folder MariaDB Berlin meetup April 2016.

1. Monty talked about improving the speed of connections to MariaDB Server, some work he’s just pushed fairly recently to the 10.2 tree.
2. Dipti spoke about MariaDB ColumnStore and it is now clear we’ll see some source/binary drop by the end of May 2016.
3. Sergei Petrunia and Vicentiu Ciorbaru spoke about the upcoming window functions that MariaDB Server 10.2.0 will see (yes, the alpha should be out real soon now).
4. Jan spoke about InnoDB in 10.2.
5. Lixun Peng spoke about a fairly interesting feature, the idea to flashback via mysqlbinlog and how you can have a “Time Machine”. I can’t wait for flashback/time machine to appear in 10.2. The demo for this is extremely good.
6. Kolbe spoke about data at rest encryption using the MariaDB Amazon AWS KMS plugin.
7. Sanja and Georg went up together to speak about 10.2 protocol enhancements as well as what you’ll see in Connector/C 3.0.
8. Wlad gave us a good rundown on authenticating with GSSAPI, something you will notice is also available in MariaDB Server 10.1’s later releases.
9. Johan Wikman gave us an introduction to MariaDB MaxScale, which started off the talks on MaxScale.
10. Markus talked about the readwritesplit plugin.
11. Massimiliano went into the Binlog server.
12. Martin didn’t use slides but gave us an amazing talk titled “Rival concepts of SQL Proxy”; it was very well given and I’ve encouraged him to write a blog post about it.
13. Community member Ben Kochie, an SRE at SoundCloud gave us a quick talk on Monitoring MySQL with Prometheus and how much they depend on the PERFORMANCE_SCHEMA.
14. Diego Dupin spoke a little about the MariaDB Java Connector, and the idea was to do a demo but the projector via HDMI seemed to be a bit wonky (this was also true of using my Mac; the VGA output however worked fine). So it was just a quick talk without any deck.

We ended with a quick Q&A session with Monty dominating it. Lots of interesting questions around why the name Maria, licensing thoughts, ensuring all the software we have are in distributions, etc. Some ended up going for pizza while others ended up in a hotel bar at the Crowne Plaza Potsdamer Platz — and the chatter went on till at least 11pm.

Thanks again to Georg Richter who found us the venue and also did a lot of the legwork with Wikimedia Foundation.

Interesting developments in the MySQL world – it can now be used as a document store and you can query the database using JavaScript instead of SQL (via the MySQL Shell). There is also a new X Plugin (see: mysql-5.7.12/rapid/) (which now makes use of protocol buffers (see: mysql-5.7.12/extra/protobuf/)). I will agree, this is more than just a maintenance release.

Do get started playing with MySQL Shell. If you’re using the yum repository, remember to ensure you have enabled the mysql-tools-preview in /etc/yum.repos.d/mysql-community.repo. And don’t forget to load the X Plugin in the server! I can’t wait for the rest of the blog posts in the series, and today just took a cursory look at all of this — kudos Team MySQL @ Oracle.

However, I’m concerned that the GA is getting what you would think of as more than just a maintenance release. We saw 5.7.11 get at rest data encryption for InnoDB, and now 5.7.12 getting even more changes. This is going to for example, ship in the next Ubuntu LTS, Xenial Xerus. Today it has 5.7.11, but presumably after release it will be upgrade to 5.7.12. I am not a huge fan of surprises in LTS releases (predictability over 5 years is a nice thing; this probably explains why I still have a 5.0.95 server running), but I guess this small band-aid is what we need to ensure this doesn’t happen going forward?

As for the other question I’ve seen via email from several folk so far: will MariaDB Server support this? I don’t see why not in the future, so why not file a Jira?

While being on the committee for the FOSDEM MySQL & friends devroom, I didn’t speak at that devroom (instead I spoke at the distributions devroom). But when I had time to pop in, I did take some notes on sessions that were interesting to me, so here are the notes. I really did enjoy Yoshinori Matsunobu’s session (out of the devroom) on RocksDB and MyRocks and I highly recommend you to watch the video as the notes can’t be very complete without the great explanation available in the slide deck. Anyway there are videos from the MySQL and friends devroom.

MySQL & Friends Devroom

MySQL Group Replication or how good theory gets into better practice – Tiago Jorge

• Multi-master update everywhere with built-in automatic distributed recovery, conflict detection and group membership
• Group replication added 3 PERFORMANCE_SCHEMA tables
• If a server leaves the group, the others will be automatically informed (either via a crash or if you execute STOP GROUP REPLICATION)
• Cloud friendly, and it is self-healing. Integrated with server core via a well-defined API. GTIDs, row-based replication, PERFORMANCE_SCHEMA. Works with MySQL Router as well.
• Multi-master update everywhere. Conflicts will be detected and dealt with, via the first committer wins rule. Any 2 transactions on different servers can write to the same tuple.
• labs.mysql.com / mysqlhighavailability.com
• Q: When a node leaves a group, will it still accept writes? A: If you leave voluntarily, it can still accept writes as a regular MySQL server (this needs to be checked)
• Online DDL is not supported
• Checkout the video

ANALYZE for statements – Sergei Petrunia

• a lot like EXPLAIN ANALYZE (in PostgreSQL) or PLAN_STATISTICS (in Oracle)
• Looks like explain output with execution statistics
• slides and video

Preparse Query Rewrite Plugins – Sveta Smirnova / Martin Hansson

• martin.hansson@oracle.com
• Query rewwriting with a proxy might be too complex, so they thought of doing it inside the server. There is a pre-parse (string-to-string) and a post-parse (parse tree) API. Pre-parse: low overhead, but no structure. Post-parse: retains structure, but requires re-parsing (no destructive editing), need to traverse parse tree and will only work on select statements
• Query rewrite API builds on top of teh Audit API, and then you’ve got the pre-parse/post-parse APIs on the top that call out to the plugins
• video

Fedora by the Numbers – Remy DeCausemaker

• Over 200,000 downloads a month for Fedora (at least this is where they could installer downloads). Upgrades don’t need an installer download though!
• https://github.com/fedora-infra/fedora-stats-tools

MyRocks: RocksDB Storage Engine for MySQL (LSM Databases at Facebook) – Yoshinori Matsunobu

• SSD/Flash is getting affordable but MLC Flash is still expensive. HDD has large capacity but limited IOPS (reducing rw IOPS is very important and reducing write is harder). SSD/Flash has great read iops but limited space and write endurance (reducing space here is higher priority)
• Punch hole compression in 5.7, it is aligned to the sector size of your device. Flash device is basically 4KB. Not 512 bytes. So you’re basically wasting a lot of space and the compression is inefficient
• LSM tends to have a read penalty compared to B-Tree, like InnoDB. So a good way to reduce the read penalty is to use a Bloom Filter (check key may exist or not without reading data, and skipping read i/o if it definitely does not exist)
• Another penalty is for delete. It puts them into tombstones. So there is the workaround called SingleDelete.
• LSMs are ideal for write heavy applications
• Similar features as InnoDB, transactions: atomicity, MVCC/non-locking consistent read, read committed repeatable read (PostgreSQL-style), Crash safe slave and master. It also has online backup (logical backup by mysqldump and binary backup by myrocks_hotbackup).
• Much smaller space and write amplification compared to InnoDB
• Reverse order index (Reverse Column Family). SingleDelete. Prefix bloom filter. Mem-comparable keys when using case sensitive collations. Optimizer statistics for diving into pages.
• RocksDB is great for scanning forward but ORDER BY DESC queries are slow, hence they use reverse column families to make descending scan a lot faster
• watch the video

The problem with Twitter is that we talk about something and before you know it, people forget. (e.g. does WebScaleSQL have an async client library?) How many blog posts are there about Percona Live Santa Clara 2015? This time (2016), I’m going to endeavour to write more than to just tweet – I want to remember this stuff, and search archives (and also note the changes that happen in this ecosystem). And maybe you do too as well. So look forward to more blogs from Percona Live Data Performance Conference 2016. In the meantime, here’s tweets in chronological order from my Twitter search.

• crowd filling up the keynote room for #perconalive
• beginning shortly, we’ll see @peterzaitsev at #perconalive doing his keynote
• #perconalive has over 1,200 attendees – oracle has 20 folk, with 22 folk from facebook
• #perconalive is going to be in Amsterdam sept 21-22 2015 (not in London this year). And in 2015, April 18-21 2016!
• We have @PeterZaitsev on stage now at #perconalive
• 5 of the 5 top websites are powered by MySQL – an Oracle ad – alexa rankings? http://www.alexa.com/topsites #perconalive
• now we have Harrison Fisk on ployglot persistence at facebook #perconalive
• make it work / make it fast / make it efficient – the facebook hacker way #perconalive
• a lot of FB innovation goes into having large data sizes with short query time response #perconalive
• “small data” to facebook? 10’s of petabytes with <5ms response times. and yes, this all sits in mysql #perconalive
• messages eventually lands in hbase for long term storage for disk #perconalive they like it for LSM
• Harrison introduces @RocksDB to be fast for memory/flash/disk, and its also LSM based. Goto choice for 100’s of services @ FB #perconalive
• Facebook Newsfeed is pulled from RocksDB. 9 billion QPS at peak! #perconalive
• Presto works all in memory on a streaming basis, whereas Hive uses map/reduce. Queries are much faster in Presto #perconalive
• Scuba isn’t opensource – real time analysis tool to debug/understand whats going on @ FB. https://research.facebook.com/publications/456106467831449/scuba-diving-into-data-at-facebook/ … #perconalive
• InnoDB as a read-optimized store and RocksDB as a write-optimized store — so RocksDB as storage engine for MySQL #perconalive
• Presto + MySQL shards is something else FB is focused on – in production @ FB #perconalive
• loving the woz keynote @ #perconalive – wondering if like apple keynotes, we’ll see a “one more thing” after this ;)
• “i’m only a genius at one thing: that’s making people think i’m a genius” — steve wozniak #perconalive
• Happiness = Smiles – Frowns (H=S-F) & Happiness = Food, Fun, Friends (H=F³) Woz’s philosophy on being happy + having fun daily #perconalive
• .@Percona has acquired @Tokutek in a move that provides some consolidation in the MySQL database market and takes..
• MySQL Percona snaps up Tokutek to move onto MongoDB and NoSQL turf http://zd.net/1ct6PEI by @wolpe
• One more thing – congrats @percona @peterzaitsev #perconalive Percona has acquired Tokutek with storage engines for MySQL & MongoDB – @PeterZaitsev #perconalive
• Percona is now a player in the MongoDB space with TokuMX! #perconalive
• The tokumx mongodb logo is a mongoose… #perconalive Percona will continue to support TokuDB/TokuMX to customers + new investments in it
• @Percona “the company driving MySQL today” and “the brains behind MySQL”. New marketing angle? http://www.datanami.com/2015/04/14/mysql-leader-percona-takes-aim-at-mongodb/ …
• We have Steaphan Greene from @facebook talk about @WebScaleSQL at #perconalive
• what is @webscalesql? its a collaboration between Alibaba, Facebook, Google, LinkedIn, and Twitter to hack on mysql #perconalive
• close collaboration with @mariadb @mysql @percona teams on @webscalesql. today? upstream 5.6.24 today #perconalive
• whats new in @WebScaleSQL ? asynchronous mysql client, with support from within HHVM, from FB & LinkedIn #perconalive
• smaller @webscalesql change (w/big difference) – lower innodb buffer pool memory footprint from FB & Google #perconalive
• reduce double-write mode while still preserving safety. query throttling, server side statement timeouts, threadpooling #perconalive
• logical readahead to make full table scans as much as 10x fast. @WebScaleSQL #perconalive
• whats coming to @WebScaleSQL – online innodb defragmentation, DocStore (JSON style document database using mysql) #perconalive
• MySQL & RocksDB coming to @WebScaleSQL thanks to facebook & @MariaDB #perconalive
• So, @webscalesql will skip 5.7 – they will backport interesting features into the 5.6 branch! #perconalive
• likely what will be next to @webscalesql ? will be mysql-5.8, but can’t push major changes upstream. so might not be an option #perconalive
• Why only minor changes from @WebScaleSQL to @MySQL upstream? #perconalive
• Only thing not solved with @webscalesql & upstream @mysql – the Contributor license agreement #perconalive
• All @WebScaleSQL features under Apache CCLA if oracle can accept it. Same with @MariaDB @percona #perconalive
• Steaphan Greene says tell Oracle you want @webscalesql features in @mysql. Pressure in public to use the Apache CLA! #perconalive
• We now have Patrik Sallner CEO from @MariaDB doing the #perconalive keynote ==> 1+1 > 2 (the power of collaboration)
• “contributors make mariadb” – patrik sallner #perconalive
• Patrik Sallner tells the story about the CONNECT storage engine and how the retired Olivier Bertrand writes it #perconalive
• Google contributes table/tablespace encryption to @MariaDB 10.1 #perconalive
• Patrik talks about the threadpool – how #MariaDB made it, #Percona improved it, and all benefit from opensource development #perconalive
• and now we have Tomas Ulin from @mysql @oracle for his #perconalive keynote
• 20 years of MySQL. 10 years of Oracle stewardship of InnoDB. 5 years of Oracle stewardship of @MySQL #perconalive
• Tomas Ulin on the @mysql 5.7 release candidate. It’s gonna be a great release. Congrats Team #MySQL #perconalive
• MySQL 5.7 has new optimizer hint frameworks. New cost based optimiser. Generated (virtual) columns. EXPLAIN for running thread #perconalive
• MySQL 5.7 comes with the query rewrite plugin (pre/post parse). Good for ORMs. “Eliminates many legacy use cases for proxies” #perconalive
• MySQL 5.7 – native JSON datatypes, built-in JSON functions, JSON comparator, indexing of documents using generated columns #perconalive
• InnoDB has native full-text search including full CJK support. Does anyone know how FTS compares to MyISAM in speed? #perconalive
• MySQL 5.7 group replication is unlikely to make it into 5.7 GA. Designed as a plugin #perconalive
• Robert Hodges believes more enterprises will use MySQL thanks to the encryption features (great news for @mariadb) #perconalive
• Domas on FB Messenger powered by MySQL. Goals: response time, reliability, and consistency for mobile messaging #perconalive
• FB Messenger: Iris (in-memory pub-sub service – like a queue with cache semantics). And MySQL as persistence layer #perconalive
• FB focuses on tiered storage: minutes (in memory), days (flash) and longterm (on disks). #perconalive
• Gotta keep I/O devices for 4-5 years, so don’t waste endurance capacity of device (so you don’t write as fast as a benchmark) #perconalive
• Why MySQL+InnoDB? B-Tree: cheap overwrites, I/O has high perf on flash, its also quick and proven @ FB #perconalive
• What did FB face as issues to address with MySQL? Write throughput. Asynchronous replication. and Failover time. #perconalive
• HA at Facebook: <30s failover, <1s switchover, > 99.999% query success rate
• Learning a lot about LSM databases at Facebook from Yoshinori Matsunobu – check out @rocksdb + MyRocks https://github.com/MySQLOnRocksDB/mysql-5.6 …
• The #mysqlawards 2015 winners #PerconaLive
• Percona has a Customer Advisory Board now – Rob Young #perconalive
• craigslist: mysql for active, mongodb for archives. online alter took long. that’s why @mariadb has https://mariadb.com/kb/en/mariadb/progress-reporting/ … #perconalive
• can’t quite believe @percona is using db-engines rankings in a keynote… le sigh #perconalive
• “Innovation distinguishes between a leader and a follower” – Steve Jobs #perconalive
• Percona TokuDB: “only alternative to MySQL + InnoDB” #perconalive
• “Now that we have the rights to TokuDB, we can add all the cool features ontop of Percona XtraDB Cluster (PXC)” – Rob Young #perconalive
• New Percona Cloud Tools. Try it out. Helps remote DBA/support too. Wonder what the folk at VividCortex are thinking about now #perconalive
• So @MariaDB isn’t production ready FOSS? I guess 3/6 top sites on Alexa rank must disagree #perconalive
• Enjoying Encrypting MySQL data at Google by @jeremycole & Jonas — you can try this in @mariadb 10.1.4 https://mariadb.com/kb/en/mariadb/mariadb-1014-release-notes/ … #perconalive
• google encryption: mariadb uses the api to have a plugin to store the keys locally; but you really need a key management server #perconalive
• Google encryption: temporary tables during query execution for the Aria storage engine in #MariaDB #perconalive
• find out more about google mysql encryption — https://code.google.com/p/google-mysql/ or just use it at 10.1.4! https://downloads.mariadb.org/mariadb/10.1.4/ #perconalive
• Encrypting MySQL data at Google – Percona Live 2015 #perconalive http://wp.me/p5WPkh-5F
• The @WebScaleSQL goals are still just to provide access to the code, as opposed to supporting it or making releases #perconalive
• There is a reason DocStore & Oracle/MySQL JSON 5.7 – they were designed together. But @WebScaleSQL goes forward with DocStore #perconalive
• So @WebScaleSQL will skip 5.7, and backport things like live resize of the InnoDB buffer pool #perconalive
• How to view @WebScaleSQL? Default GitHub branch is the active one. Ignore -clean branches, just reference for rebase #perconalive
• All info you need should be in the commit messages @WebScaleSQL #perconalive
• Phabricator is what @WebScaleSQL uses as a code review system. All diffs are public, anyone can follow reviews #perconalive
• automated testing with jenkins/phabricator for @WebScaleSQL – run mtr on ever commit, proposed diffs, & every night #perconalive
• There is feature documentation, and its a work in progress for @WebScaleSQL. Tells you where its included, etc. #perconalive
• Checked out the new ANALYZE statement feature in #MariaDB to analyze JOINs? Sergei Petrunia tells all #perconalive https://mariadb.com/kb/en/mariadb/analyze-statement/ …

SCALE14x was held at Pasadena, Los Angeles this year from January 21-24 2016. I think its important to note that the venue changed from the Hilton LAX — this is a much bigger space, as the event is much bigger, and you’ll also notice that the expo hall has grown tremendously.

I had a talk in the MySQL track, and that was just one of over 180 talks. There were over 3,600 people attending, and it showed by the number of people coming by the MariaDB Corporation booth. I spent sometime there with Rod Allen, Max Mether, and Kurt Pastore, and the qualified leads we received were pretty high. Of course it didn’t hurt that we were also giving away a Sphero BB-8 Droid.

The MySQL track room was generally always full. We learned some interesting tidbits like Percona Server 5.7 would be GA in February 2016 (true!), the strong crowd at the MariaDB booth and quite a bit more. People are definitely interested in MySQL 5.7’s JSON functionality.

The highlight of my talk, The MySQL Server Ecosystem in 2016 was that it brought along quite a good discussion on Twitter. Its clear people are very interested in this and there is much opportunity for writing about this!

The Mark Shuttleworth keynote

But there were other SCALE14x highlights, like the keynote by Mark Shuttleworth. It was generally a very moving keynote, and here are a few bits that I took as notes:

• Technology changes lives
• Society evolves because it becomes possible to live differently
• New software moves too fast for distributions (6 months is too long). Look at Github. Speed vs. integration/trust/maintenance (the work of a distro)
• snapcraft 2.0 (learn more about your first snap): reduce the amount of work to package software. Install software together transactionally.

An overview of a next-gen filesystem

Another talk I found interesting was the talk about bitrot, and filesystems like btrfs and ZFS. Best to read the presentation, and the article that was referenced.

Scaling GlusterFS at Facebook

A talk by Facebook is usually quite full, and I was interested in how they were using GlusterFS and if anyone has managed to successfully run a database over it yet (no). This was a talk given by Richard Wareing who’s been at Facebook for over 5 years:

• GB’s to many PBs, 100’s of millions of files. QPS (FOPs) is 10s of billions per day, namespace (volume), TBs to PBs and Bricks: 1000’s. Version 3.3.x is when they started and now they use 3.6.x (trail mainline closely)
• Use cases: archival, backing data store for large scale applications, anything that doesn’t fit into other DBs
• RAID6, controller is enterprise grade, storage is more consumer grade
• Primarily using XFS, and are starting to use btrfs (about 20% of the fleet run on it)
• closed source AntFarm, JD, and their IPv6 support (they removed IPv4 support). They have JSON Statistic dumps which they contributed upstream.
• a good mantra, pragmatism over correctness

Some expo hall chatter

There was plenty to followup post-SCALE14x with many having questions about MariaDB Server, or wanting to buy services around it from MariaDB Corporation. I learned for example that Rackspace maintains their own IUS repository of packages they think their customers will find important to use. The idea behind it is that its Inline with Upstream Stable. Naturally you will find MariaDB Server as well as packages for all the engines like CONNECT.

I also learned that Stacki uses MariaDB Server for provisioning, as was evidenced by their github issue.

Its incredibly rewarding to note that pretty much everyone knew what MariaDB Server was. Its been a long journey (six years!) but it sure feels sweet. Ilan and his team put on a great SCALE so I can’t wait to be back again next year.

Over the weekend I read in the FT (paywall): Is Brussels safe? Ring a local resident to find out. I’m sure it will be fine, and you will want to be there for FOSDEM, happening 30-31 January 2016. 

There is the excellent one day track, that is the MySQL & Friends Devroom (site). Talks hail from Oracle, MariaDB Corporation, Percona and more. We don’t have a booth this year, but we do have amazingly good content on Saturday. I’m happy to have been part of the committee that chose the talks, but you know that this is a labour of love put on by Frédéric Descamps, Liz van Dijk, Dimitri Vanoverbeke, and Kenny Gryp. I’m sure the party will be awesome.

But that is not all! In the distributions devroom, you can see me give a talk at 11:00-11:20 titled Distributions from the view of a package. This is an important topic, because you start seeing MariaDB Server becoming the default in many distributions with the last holdout being Debian. But there is a lot of discussion, especially from the security standpoint there now, about MySQL overall. But that’s not the focus of my talk – I’m going to talk to you about how we, as upstream, have had to deal with distributions, changing requirements, etc. overall. I’ve done this since the MySQL days, so have quite a bit of experience dealing with it. 

If you are making software and want to be included and supported across all distributions, I highly recommend you coming to my talk. If you happen to decide to live in an ecosystem where there are forks, I also promise to make it useful for you.

And on Sunday, you will want to go visit the RocksDB Storage Engine for MySQL talk by none other than Yoshinori Matsunobu of Facebook. This will be at the main track and I highly recommend you visit it – I’m sure Sergei Petrunia will also make an appearance as he spends a lot of time on this too.

All in, I’m extremely excited to be at FOSDEM 2016. And you don’t need to ring a local resident to find out if its going to be safe/fun – come for the learning, stay for the beer ;-)