ProxySQL in its versions up to 1.x did not natively support Percona XtraDB Cluster (PXC). Instead, it relied on the flexibility offered by the scheduler. This approach allowed users to implement their own preferred way to manage the ProxySQL behaviour in relation to the Galera events. From version 2.0 we can use native ProxySQL support for PXC.. The mechanism to activate native support is very similar to the one already in place for group replication. In brief it is based on the table [runtime_]mysql_galera_hostgroups and the information needed is mostly the same:

• writer_hostgroup: the hostgroup ID that refers to the WRITER
• backup_writer_hostgroup: the hostgoup ID referring to the Hostgorup that will contain the candidate servers
…

I just encountered the problem described in the title, on a server I don’t have enough free space for create a backup as long the replica is catching up, because the relay logs eats all the available free space as the IO thread works faster than the SQL thread in the replication. What to do? […]

Network is a major part of a database infrastructure. However, often performance benchmarks are done on a local machine, where a client and a server are collocated – I am guilty myself. This is done to simplify the setup and to exclude one more variable (the networking part), but with this we also miss looking at how network affects performance.

The network is even more important for clustering products like Percona XtraDB Cluster and MySQL Group Replication. Also, we are working on our Percona XtraDB Cluster Operator for Kubernetes and OpenShift, where network performance is critical for overall …

Percona is glad to announce the release of Percona Server 5.7.25-28 on February 18, 2019. Downloads are available here and from the Percona Software Repositories.

This release is based on MySQL 5.7.25 and includes all the bug fixes in it. Percona Server 5.7.25-28 is now the current GA (Generally Available) release in the 5.7 series.

All software developed by Percona is open-source and free.

In this release, Percona Server introduces the …

Ahead of the PCI move to deprecate the use of ‘early TLS’, we’ve previously taken steps to disable TLSv1.0.

Unfortunately at that time we encountered some issues which led us to rollback these changes. This was to allow users of operating systems that did not – yet – support TLSv1.1 or higher to download Percona packages over TLSv1.0.

Since then, we have been tracking our usage statistics for older operating systems that don’t support TLSv1.1 or higher at https://repo.percona.com. We now receive very few legitimate requests for these downloads.

Consequently,  we are ending support for TLSv1.0 on all Percona web properties.

A Guest Post from Jordan Raine, Clio

Jordan Raine is a staff software developer at Clio, the leading provider of legal practice management, client relationship management, and client intake software. Clio is dedicated to helping lawyers meet client needs and run efficient, profitable practices. Jordan wrote this post to help mySQL developers save time/effort and ultimately improve their customers' experience. 

Unlike most code a developer writes, writing SQL only requires us to describe what data we want and not how to get it. When given a query like SELECT id, author_id FROM posts WHERE author_id = 123 ORDER BY id, you needn’t concern yourself with what indexes are used (if any), what type of sort is used, or any other number of implementation details. Instead, the query optimizer handles this for you. This keeps SQL concise and …

While implementing ClickHouse for query executions statistics storage in Percona Monitoring and Management (PMM),  we were faced with a question of choosing the data type for metrics we store. It came down to this question: what is the difference in performance and space usage between Uint32, Uint64, Float32, and Float64 column types?

To test this, I created a test table with an abbreviated and simplified version of the main table in our ClickHouse Schema.

The “number of queries” is stored four times in four different columns to be able to benchmark queries referencing different columns.  We can do this with ClickHouse because it is a column store and it works only with columns referenced by the query. This method would not be appropriate for testing on …

Mydbops database meetup was held on 26-01-2019 and 48 members from open source database community has attended this event. We had talks on MySQL and MongoDB databases.

Open source database enthusiastic from companies like OLA Cabs, Searce Inc, PayTm, Quikr, Zensar, Grab, SAP labs, Travel Yarri, Meddiff and a few has travelled from other cities of India like Hyderabad and Chennai.

The Welcome talk was given my Selva venkatesh of Mydbops. He spoke about the open source database community and welcomed all the participants and speakers.

Followed by it Karthik P R , CEO/ Founder, Mydbops made his presentation on “InnoDB Performance Optimisation” . InnoDB is the prime engine in MySQL.This talk focuses on the InnoDB Architecture in MySQL 8.0 and its fine tuning. He also answered the various questions raised …

For those not familiar with it, FOSDEM is an amazing, free entry, full on celebration of open source that takes place in Brussels, Belgium every year. This year the event was held over the first weekend of February. Fringe events, such as the Pre-FOSDEM MySQL day hosted by Oracle MySQL, and the community dinner that follows, provide an opportunity to network.

In case you didn’t make it to FOSDEM this year, here are links to Percona’s presentations from the event. Organizers video and share online every talk from every dev room, a phenomenal achievement in itself. All credit to the volunteers who run this show.

Database Dev Room: Hugepages and databases presented by Fernando Laudares …

Recently, I had to work on an emergency for a customer who was having a problem restarting a MariaDB Galera Cluster. After a failure in the cluster they decided to restart the cluster entirely following the right path: bootstrapping the first node, and then adding the rest of the members, one by one. Everything went fine until one of the nodes rejected the request to join the cluster.

Given this problem, the customer decided to ask us to help with the problematic node because none of the tests they did worked, and the same symptom repeated over and over: SST started, copied few gigs of data and then it just hanged (apparently) while the node remained out of the cluster.

Identifying the issue…

Once onboard with the issue, initially I just checked that the cluster was trying a SST: given the whole dataset was about 31GB I decided to go directly to a healthy solution: to clean up the whole datadir and start afresh. No luck …