This blog post will discuss what is necessary of the Percona Live Advanced Percona XtraDB Cluster tutorial.
Percona Live 2016 is happening in April! If you are attending, and you are registered to the Percona XtraDB Cluster (Galera) tutorial presented by Kenny and myself, please make sure that you:
Starting with MySQL 5.7, performance_schema has been enhanced to instrument metadata locks, and can be turned on by adding the following line to your my.cnf file:
performance-schema-instrument='wait/lock/metadata/sql/%=ON'
(At runtime, it can also be enabled by modifying the setup_instruments table in performance_schema.)
From here, you can now query performance_schema.metadata_locks to reveal all currently open metadata locks on your server:
mysqlselect * from performance_schema.metadata_locks\G *************************** 1.
…
This blog is an EXPLAIN FORMAT=JSON wrap-up for the series of posts I’ve done in the last few months.
In this series, we’ve discussed everything unique to
EXPLAIN FORMAT=JSON
. I intentionally skipped a description of members such as
table_name
,
access_type
or
select_id
, which are not unique.
In this series, I only mentioned in passing members that replace information from the
Extra
column in the regular
EXPLAIN
output, such as
using_join_buffer
,
partitions
,
using_temporary_table
or simply
…[Read more]Join us for our latest webinar on Thursday, April 7, at 10 am PDT (UTC-7) on Introduction to Troubleshooting Performance: What Affects Query Execution?
MySQL installations experience a multitude of issues: server hangs, wrong data stored in the database, slow running queries, stopped replications, poor user connections and many others. It’s often difficult not only to troubleshoot these issues, but to even know which tools to use.
Slow running queries, threads stacking for ages during peak times, application performance suddenly lagging: these are some of the things on a long list of possible database performance issues. How can you figure out why your MySQL installation isn’t …
[Read more]See Bill Nye the Science Guy at Percona Live Data Performance Conference, and help an excellent cause!
The best science is built on solid data. As a world-renown icon in tech and geek circles everywhere, Bill Nye fights to raise awareness of the value of science, critical thinking, and reason. He hopes that the data he brings will help inspire people everywhere to change the world. And seeing as the open source community is full of science-minded individuals, he is excited to speak to everyone at Percona Live!
Since his early days as a comedian, to creating his well-known …
[Read more]
The optimizer in MySQL 5.7 leverages generated columns. Generated
columns will physically store data in two cases: Either the
column is defined as STORED or you create an index on a virtual
column. The optimizer will leverage such an index automatically
if it encounters the same expression in a statement. Let's see an
example:
mysql> DESC squares;
+-------+------------------+------+-----+---------+-------+
| Field |
Type
| Null | Key | Default | Extra |
+-------+------------------+------+-----+---------+-------+
| dx | int(10) unsigned | YES
| | NULL
| |
| dy | int(10) unsigned | YES
| | NULL
| |
…
It is not uncommon that we need to filter out some DBs or Tables while setting up replication. It is important to understand how MySQL evaluates/process the replication filtering rules to avoid the conflicting or confusion while we setting them up.The purpose of this blog is to illustrate the rules and provide some suggestions for best practice.
MySQL provides 3 levels of filters for setting up replication: Binary log, DB and Table. The binlog filters apply on the master to control how to log the changes. Since MySQL replication is based on the binlog, it is the first level filter and has the highest priority. While the DB-level and Table-level filters apply on the slaves, since each table belongs to a schema, the DB-level filters have higher priority than the Table-level ones. Inside the Table-level filters, MySQl will evaluate the options in the order of: …
[Read more]Percona is glad to announce the first GA release of Percona XtraBackup 2.4.2 on April 1st, 2016. Downloads are available from our download site and from apt and yum repositories.
Percona XtraBackup enables MySQL backups without blocking user queries, making it ideal for companies with large data sets and mission-critical applications that cannot tolerate long periods of downtime. Offered free as …
[Read more]Historical MySQL Bug#2, opened 12 Sep 2002, states that MySQL Connector/J doesn’t make toast. It hasn’t been fixed for more than 14 years. I’ve finally created a patch for it.
First of all: why only fix this for MySQL Connector/J? We should make sure the server can do this for any implementation! With this fix, now MySQL server (starting with version 5.1) can make toast.
There are few dependences though (see assembled setup picture):
Come meet the MariaDB Server and MariaDB MaxScale developers in Berlin (April 12 2016), talk about new upcoming things in MariaDB Server 10.2, as well as the next MariaDB MaxScale releases. Let’s not forget the talks about the upcoming developments with the Connectors.
It will be a fun-filled, information-packed night. Food & drink will be provided.
For more information and the opportunity to RSVP check-out our meetup page. RSVP soon as we only have 99 spaces available.
