MySQL 5.7.12 is the fourth stable (GA) release of the MySQL 5.7 series. It brings with it the usual bug fixes and incremental enhancements that you would expect with a point release. Except this time things are a little bit different.…
In this blog, we will examine the differences between GCache and Record-Set Cache in Percona XtraDB Cluster.
In Percona XtraDB Cluster (PXC), there is the concept of GCache and Record-Set cache (which can also be called transaction write-set cache). The use of these two caches is often confusing if you are running long transactions, as both of them result in the creation of disk-level files. Let’s understand what their main differences are.
Record-Set Cache
- When you run a long-running transaction on any particular node, it will try to append a key for each row that it tries to modify (the key is a unique identifier for the row {db,table,pk.columns}). This information is cached in out-write-set, which is then sent to the group for …
In this blog, we’ll discuss how the Percona XtraDB Cluster threading model works.
Percona XtraDB Cluster (PXC) creates a different set of threads to service its operations. These threads are in addition to existing MySQL threads. Let’s understand what these threads are and how they’re used. There are three main groups of threads:
-
Applier thread(s)
- Applier threads are meant to apply write-sets that the
node receives from other nodes (through cluster).
(write-message is directed through
gcv_recv_thread
.) - The number of applier threads is controlled using the
wsrep_slave_thread
configuration. (The default value is 1, so at least one wsrep applier thread …
- Applier threads are meant to apply write-sets that the
node receives from other nodes (through cluster).
(write-message is directed through
This blog post will discuss the issues and solutions for MySQL Data at Rest encryption.
Data at Rest Encryption is not only a good-to-have feature, but it is also a requirement for HIPAA, PCI and other regulations.
There are three major ways to solve data encryption at rest:
- Full-disk encryption
- Database-level (table) encryption
- Application-level encryption, where data is encrypted before being inserted into the database
I consider full disk encryption to be the weakest method, as it only protects from someone physically removing the disks from the server. Application-level encryption, on the other hand, is the best: it is the most flexible method with almost no overhead, and it also solves data in-flight encryption. Unfortunately, it is not always possible …
[Read more]And the first two Database Performance Team characters are . . .
The last blog introduced the Database Performance Team. The Database Performance Team is comprised of our services experts, who work tirelessly every day to guarantee the performance of your database. Percona’s services team is made up of superheroes that make sure your database is running at peak performance. Now we’re ready to reveal the identity of the first two team members.
The first is funny, friendly, quick-witted, supporting, fast and courteous – but still able to get the job done with amazing competence. Who is this champion?
…
[Read more]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 …
[Read more]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 …
Earlier this week we had a discussion with fellow DBAs about our mysql prompts, and at the end of the day it showed up, that a lot of us hit the same problem. The problem is, that when you set up your mysql prompt then ‘\h’ will be resolved to ‘localhost’ when you connect locally […]
Earlier this week we had a discussion with fellow DBAs about our mysql prompts, and at the end of the day it showed up, that a lot of us hit the same problem. The problem is, that when you set up your mysql prompt then ‘\h’ will be resolved to ‘localhost’ when you connect locally […]
This blog will look at MySQL 5.7 sysbench OLTP read-only results to determine if they are faster than previous versions.
As promised in my previous post, I have checked MySQL 5.7 performance against previous versions in a different workload. This time, I will use sysbench OLTP read-only transactions (read-write transactions are part of future research, as there is more tuning required to get the best performance in write workloads).
One important thing to mention is that MySQL 5.6 and 5.7 have
special optimizations for READ-ONLY transactions. In MySQL 5.6,
however, you need to start a transaction with
"START TRANSACTION READ ONLY" to get the …