Tue, 2015-09-01 11:17jean-francoisgagne

Parallel replication is a much-expected feature of MySQL. It is available in MariaDB 10.0 and in MySQL 5.7. In this 3rd post of the series, we present benchmark results from Booking.com production environments.

This is a repost of Jean-François Gagné's blog post on blog.booking.com.

Note: this post has an annex: Under the Hood. Benchmarking is a complex art and reporting results accurately is even harder. If all the details were put in a single article, it …

Using mysql command line utility to get recordsets, the data rows alignment and line breaks are often  a mess. You can use the command line tool on a mysql database server to get a set of rows into an output TSV file like so: shell> mysql -u your_user -p < your_statement.sql > data.csv I came up with the following python script to grab the output file and pretty print:

You can put your own

Booking.com, one of the world’s leading e-commerce companies, helps travels book nearly 1 million rooms per night. Established in 1996, Booking.com B.V. guarantees the best prices for any type of property, from small, family-run bed and breakfasts to executive apartments and five-star luxury suites.

The travel website is also a dedicated contributor to the MySQL and Perl community. Other open source technologies include CentOS Linux, Nginx, python, puppet, Git and more.

A Diamond sponsor of Percona Live Amsterdam Sept. 21-23, you can meet the people who power Booking.com at booth 205. Enter promo code “BlogInterview” at registration to save €20!

In the meantime, meet Jean-François Gagné, a system engineer at Booking.com. He’ll be presenting a couple of talks: “ …

Hi Daniël,
Very good point, and apologies for not replying sooner, holidays, but more importantly, I wanted to reply with a confirmation: you’re absolutely right. I upgraded my old workbench to 6.3.4, which comes with SYS 1.4.0 and hey presto, 19 new tables in SYS, of which:
+————–+———————+————–+
| column_name | table_name | table_schema |
+————–+———————+————–+
| waiting_pid | innodb_lock_waits | sys |
| blocking_pid | innodb_lock_waits | sys |
| waiting_pid | x$innodb_lock_waits | sys |
| blocking_pid | x$innodb_lock_waits | sys |
+————–+———————+————–+
I’ll see if we can get/propose something similar for NDB tables & locks…
Thanks.

Today, Devart is proud to announce the release of a new product – dbForge Data Generator for MySQL v1.0!

There can be a lot of confusion and lack of planning in Percona XtraDB Clusters in regards to nodes becoming desynchronized for various reasons.  This can happen a few ways:

• An IST or SST joining node catching up after a state transfer (Joined/Joining state)
• Using wsrep_desync for something like a backup
• Executing a rolling-schema-upgrade using using wsrep_OSU_method=RSU

When I say “desynchronized” I mean a node that is permitted to build up a potentially large wsrep_local_recv_queue while some operation is happening.  For example a node taking a backup would set wsrep_desync=ON during the backup and potentially fall behind …

Previous episodes:

• MySQL replication monitoring 101

MySQL replication in action - Part 1: GTID & CoMySQL replication in action - Part 2 - Fan-in topologyMySQL replication in action - Part 3 - All-masters P2P topologyMySQL replication in action - Part 4 - star and hybrid topologies
Parallel replication overviewOne of …

A couple of months ago I wrote about how you can use the MDX functions Ancestors() and Ascendants to retrieve the full lineage of members. (See: "MDX: retrieving the entire hierarchy path with Ancestors()".)

As you might recall, the immediate reason to write about those functions was to find a pure MDX solution to implement the "Show Parents" / "Hide Parents" functionality offered by OLAP cube browsers. To recap, developers of MDX-based pivot tables face a challenge when rendering the result of a query like this:

SELECT    CrossJoin(
            [Product].[Product].Members,
 …

We will have three presentations about new coming Galera Cluster 4.0.  The presenter will be Seppo Jaakola, CEO and co-founder of Codership and Philip Stoev, QA and Release Manager for Galera Cluster for MySQL

Big Transactions on Galera Cluster

22 September 3:10PM – 4:00PM @ Lausanne

Big and long term transactions have traditionally not behaved well in Galera Cluster. Large replication data sets have resulted in symptoms like elevated conflict rate, increased memory consumption, even OOM kill may happen, flow control pausing, cluster freezing… To deal with these issues, Galera users have been adviced to split large transactions in “reasonable size”. There is also cluster configuration option for rejecting too large transactions, as a safe guard.

This presentation explains the new large transaction replication method in Galera Cluster 4.0, which can now replicate transactions of any size, with minimal …

In my last Booking.com Hackathon, I worked on MyISAM vs InnoDB for data loading (LOAD DATA IN FILE) and bulk index creation.  My motivation was the following: knowing that some are still using MyISAM for this particular use-case, I wanted to verify/understand if/why InnoDB is slower than MyISAM.  I do not yet have complete results on this specific subject but I found some interesting things that