This post is a sister post to MySQL Master Replication Crash Safety Part #5: making things faster without reducing durability. There is no introduction or conclusion to this post, only landing sections: reading this post without its context is not not recommended. You should start with the main post and come back here for more details.
And this Part #5 of the series has many sub-parts. So far,
This is a follow-up post in the MySQL Master Replication Crash Safety series. In the three previous posts, we explored the consequence of reducing durability on masters (including setting sync_binlog to a value different from 1). But so far, I only quickly presented why a DBA would run MySQL with such configuration. In this post, I present actual benchmark results. I also present a
This post is a sister post to MySQL Master Replication Crash Safety Part #4: benchmarks of high and low durability. There are no introduction or conclusion to this post, only landing sections: reading this post without its context is not recommended. You should start with the main post and come back here for more details.
Environment
My benchmark environment is composed of three vms in
Here are my slides about MySQL 8.0 Scalability & Benchmarks from Percona LIVE 2019 in Austin, TX. (and I also realized I forgot to publish my slides from MySQL pre-FOSDEM 2019 Day about MySQL Performance Tuning, so fixing it now ;-))
P.S. Percona LIVE was "just awesome" ! ;-))
Rgds,
-Dimitri
In this research, I wanted to see what kind of performance improvements could be gained by using a ClickHouse data source rather than PostgreSQL. Assuming that I would see performance advantages with using ClickHouse, would those advantages be retained if I access ClickHouse from within postgres using a foreign data wrapper (FDW)? The FDW in question is clickhousedb_fdw – an open source project from Percona!
The database environments under scrutiny are PostgreSQL v11, clickhousedb_fdw and a ClickHouse database. Ultimately, from within PostgreSQL v11, we are going to issue various SQL queries routed through our clickhousedb_fdw to the ClickHouse database. Then we’ll see how the FDW performance compares with those same queries executed in native PostgreSQL and native ClickHouse.
Clickhouse Database
ClickHouse is an open source column based database management system which can achieve performance of between 100 and …
[Read more]Sysbench has long been established as the de facto standard when it comes to benchmarking MySQL performance. Percona relies on it daily, and even Oracle uses it when blogging about new features in MySQL 8. Sysbench comes with several pre-defined benchmarking tests. These tests are written in an easy-to-understand scripting language called Lua. Some of these tests are called: oltp_read_write, oltp_point_select, tpcc, oltp_insert. There are over ten such scripts to emulate various behaviors found in standard OLTP applications.
But what if your application does not fit the pattern of traditional OLTP? How can you continue to utilize the power of load-testing, benchmarking, …
[Read more]In this post, I want to explore a way to establish 100,000 connections to MySQL. Not just idle connections, but executing queries.
100,000 connections. Is that really needed for MySQL, you may ask? Although it may seem excessive, I have seen a lot of different setups in customer deployments. Some deploy an application connection pool, with 100 application servers and 1,000 connections in each pool. Some applications use a “re-connect and repeat if the query is too slow” technique, which is a terrible practice. It can lead to a snowball effect, and could establish thousands of connections to MySQL in a matter of seconds.
So now I want to set an overachieving goal and see if we can achieve it.
Setup
For this I will use the following hardware:
Bare metal server provided by packet.net, instance size:
c2.medium.x86
Physical Cores @ 2.2 GHz
(1 X AMD EPYC 7401P)
Memory: 64 GB of …
Percona Server for MySQL 8.0 comes with enterprise grade total data encryption features. However, there is always the question of how much overhead – or performance penalty – comes with the data decryption. As we saw in my networking performance post, SSL under high concurrency might be problematic. Is this the case for data decryption?
To measure any overhead, I will start with a simplified read-only workload, where data gets decrypted during read IO.
During query execution, the data in memory is already decrypted so there is no additional processing time. The decryption happens only for blocks that require a read from storage.
For the benchmark I will use the following workload:
sysbench …[Read more]
MySQL 8.0.15 performs worse in sysbench oltp_read_write than MySQL 5.7.25
Initially I was testing group replication performance and was puzzled why MySQL 8.0.15 performs consistently worse than MySQL 5.7.25.
It appears that a single server instance is affected by a performance degradation.
My testing setup
Hardware details:
Bare metal server
provided by packet.net, instance size: c2.medium.x86
24 Physical Cores @ 2.2 GHz
(1 X AMD EPYC 7401P)
Memory: 64 GB of ECC RAM
Storage : INTEL® SSD DC S4500, 480GB
This is a server grade SATA SSD.
Benchmark
sysbench oltp_read_write --report-interval=1 --time=1800 --threads=24 --tables=10 --table-size=10000000 --mysql-user=root --mysql-socket=/tmp/mysql.sock run
In the following summary I used these combinations:
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 …
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