Migrating Facebook to MySQL 8.0

Perhaps it's due to me being in the PostgreSQL camp, but what happened to MariaDB? I was convinced that's where MySQL developers went and that's where development proceeded, while MySQL was just half dead, because Oracle did not care about it.

MySQL 5.6 was released on 5 February <i>2013</i>.<p>MySQL 8.0 was released on 19 April <i>2018</i>.<p>&gt;The 8.0 migration has taken a <i>few years</i> so far. We have converted many of our InnoDB replica sets to running entirely on 8.0.<p>At the scale of Facebook I wonder if they are the largest MySQL user on the planet.<p>And I take this opportunity to ask, does anyone know how does the MySQL roadmap works? What sort of features are coming or when is 9.0 expected to arrive.

Thanks, HermanL and PradeepN, for sharing this migration story with HN!<p>You wrote:<p>&quot;Despite all the hurdles in our migration path, we have already seen the benefits of running 8.0.&quot;<p>May I ask what are the main performance benefits you have measured&#x2F;noticed?

It&#x27;s interesting to see FB migrating so much over to Oracle.<p>2 weeks ago was FB use of GraalVM (from Oracle). And now this.<p><a href="https:&#x2F;&#x2F;news.ycombinator.com&#x2F;item?id=27782475" rel="nofollow">https:&#x2F;&#x2F;news.ycombinator.com&#x2F;item?id=27782475</a>

Wow. I worked on the upgrade from 5.0 to 5.1 (I think). We had fewer than 100 patches at the time. 1700 sounds like a nightmare. I apologize for any and all of the patches I wrote.

&gt; MySQL, an open source database developed by Oracle<p>This makes it sound like Oracle created it, when it fact the reality is the opposite: Oracle fought it, and bought Sun just so they could get their hands on MySQL. How did regulators let that happen is beyond me.

&gt;It took a couple of years to complete porting all of these features. By the time we got to the end, we had evaluated more than 2,300 patches and ported 1,500 of those to 8.0.<p>This is some tremendous effort as I see. I wonder how many people work on these evaluations.

+1 for MyRocks. If you can, try it. We store some text data and the compression is over 10 times better than InnoDB with a significative speedup.

Go MySQL - solid open source database rocking for the last almost 3 decades!

Anyone else puzzled by the shaking migration animation? The original file has a 1920x1080 resolution. I wonder if it is related to the shaking. Good article nevertheless.

I wonder what order of magnitude of rows they deal with and how they optimize indices for querying that data.

I&#x27;d love to know roughly how many engineers (or engineer hours) this took - sounds like a mammoth project!

Seems like good, old-fashioned engineering work to me. No breathless evangelism or careerist claptrap in sight.

My old-man brain still can&#x27;t compute this statement: <i>&quot;MySQL, an open source database developed by Oracle&quot;</i>. I know this is now factually true, but late-90s me keeps looking over my shoulder and freaking out.

&gt; A few applications hit repeatable-read transaction deadlocks involving insert … on duplicate key queries on InnoDB. 5.6 had a bug which was corrected in 8.0, but the fix increased the likelihood of transaction deadlocks.<p>Interesting, I&#x27;ve run into a bug in MySQL 5.6 involving select for update where it deadlocked when it shouldn&#x27;t. I wonder if the two were related.

Where can I read more about the custom things FB added to MySQL 5.6? Their work on replication and the DDL work seems fascinating. Are there scholarly papers, white-papers, blogs?<p>Are they storing the friend graph in MySQL?

&gt; First, we could not upgrade servers in place and needed to use logical dump and restore to build a new server. However, for very large mysqld instances, this can take many days on a live production server and this fragile process will likely be interrupted before it can complete.<p>This part is quite interesting. I&#x27;d think it will take maybe a day to dump&#x2F;restore a database with a single 10TB table with no parallelism, at a speed of about 120MB&#x2F;s. How big is these mysqld instances such that the process will take many days?

What I take away from this is that they are (or were, until recently) still running production systems on MySQL 5.6...

Really well done article. In-xeptjh treatment of a problem that few will actually tackle - a migration at Facebook&#x27;s MySQL scale.<p>Would be really good to see how long the project took and the migration speed they achieved.

Anyone else notice that bad scaling and jumping on the animation? If they&#x27;re going for an old informational film aesthetic, awesome!

Do you know if they use the Percona toolkit with MySQL? Does it even give any benefits if one is running MySQL 8?

can it do DDL commands in a transaction yet?

Only oldies uses Facebook in 2021

So first sentence is:<p>&quot;MySQL, an open source database developed by Oracle, powers some of Facebook’s most important workloads. &quot;<p>Oracle didn&#x27;t develop MySQL, they bought it... Am I nit-picky here, opinions?<p>Otherwise, congrats on shipping!

&quot;MySQL, an open source database developed by Oracle&quot; - Gawd! Were most devs at FB born after the acquisition?

I&#x27;d be interested more in what features were in their (3):<p>&gt; Non-MyRocks Server: Features in the mysqld server that were not related to our MyRocks storage engine were ported.<p>i.e. things that they haven&#x27;t shared with the MySQL community but aren&#x27;t related to the storage layer. Why would&#x2F;should they keep those private? Considering that RocksDB is open-source, clearly it&#x27;s unlikely it&#x27;s because they&#x27;re &#x27;trade secrets&#x27;.

&gt;&quot;MySQL, an open source database developed by Oracle, &quot;<p>Sorry but there is a difference between &quot;developed&quot; as in originally created and &quot;being developed&quot; which is the case here in relation to Oracle.

Only commenting to say their site makes me mad cause it breaks the browser history. I click the link, go to the fb engineering site, and the back button has no history to go back to HN. Dark Pattern UX -- gross.

&gt; MySQL, an open source database <i>developed</i> by Oracle<p>Dear Facebook:<p>Please fix the wording emphasized above ASAP before we revolt here in outrage with your lack of attention to detail. MySQL was developed by relevant open source project contributors (initially, MySQL AB folks), but not by Oracle and even not by Sun Microsystems. MySQL has been in development for ~12 years before Sun acquired MySQL AB. Please set the record straight.<p>Sincerely,<p>MySQL user (not currently, but in the past and maybe in the future [though unlikely, because Postgre...] :-)