Recently, I had to go through crash recovery of a large MariaDB 10.1.21 instance. After starting MariaDB, I started tailing the error logs expecting to wait many minutes while InnoDB was scanning ibd files. I was surprised (and actually delighted) with this:
[...] [...]:34:36 [...] [Note] InnoDB: Reading tablespace information from the .ibd files... [...]:34:53 [...] [Note] InnoDB: Processed
MySQL Enterprise Backup Team is pleased to announce major improvements in incremental backup performance starting with release 4.1.
Introduction
The current incremental backup algorithm scans all the tables to gather changed pages even if very few tables are modified since the previous backup and thus results in a 'full-scan' incremental backup. This may result in increment backups requiring the same amount of time as full backup because it scans all the tables. The new algorithm aims to eliminate this extra time.
The new algorithm scans only those tables that have been modified since the previous backup. This algorithm relies on modification time, which is similar to an earlier improvement made for full backup. That full backup algorithm is known as optimistic full backup, hence new improvement is named …
[Read more]In this blog post, I’ll look for the bottleneck that prevented the performance in my previous post from achieving better results.
The powerful machine I used in the tests in my previous post has a comparatively slow disk, and therefore I expected my tests would hit a point when I couldn’t increase performance further due to the disk speed.
Hardware configuration:
Processors: physical = 4, cores = 72,
virtual = 144, hyperthreading = yes
Memory: 3.0T
Disk speed: about 3K …
Percona announces the GA release of Percona Server for MySQL 5.7.17-11 on February 3, 2017. Download the latest version from the Percona web site or the Percona Software Repositories.
Based on MySQL 5.7.17, including all the bug fixes in it, Percona Server for MySQL 5.7.17-11 is the current GA release in the Percona Server for MySQL 5.7 series. Percona’s provides completely open-source and free software. Find release details in the …
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Almost a year ago I've got really interested in MyRocks and
built MySQL from Facebook that provides it
from source. Since that time I build it from fresh sources few
times per week (as I've described in that post) and once in a while try to work with it
and study some details or use cases. Today I'd like to discuss
one of them that I've recently studied with perf profiler.
This is not only because I am going to talk about applying profilers to all kinds and forks
of MySQL at FOSDEM 2017 MySQL & Friends …
Oprofile was widely used for MySQL profiling
on Linux in the past. But since 2010 and 2.6.31 Linux kernels
another profiler, perf, gets increasing popularity. It uses
performance counters (CPU hardware registers that count hardware
events such as instructions executed) subsystem in Linux.
perf is capable of lightweight profiling. It is included
in the Linux kernel, under tools/perf (so features
available depends on kernel version), and is frequently updated
and enhanced.
So, probably perf is the future of profiling on Linux and
it makes sense to discuss its basic usage for profiling MySQL
servers. For detailed discussions of features provided, numerous
examples (not related to MySQL) and links I suggest to read …
Welcome to another post in the series of Percona Live featured tutorial speakers blogs! In these blogs, we’ll highlight some of the tutorial speakers that will be at this year’s Percona Live conference. We’ll also discuss how these tutorials can help you improve your database environment. Make sure to read to the end to get a special Percona Live 2017 registration bonus!
In this Percona Live featured tutorial, we’ll meet Frédéric Descamps, MySQL Community Manager at Oracle. Frédéric is probably better known in the community as “LeFred” (Twitter: @lefred)! His tutorial is …
[Read more]Please join Laurynas Biveinis, Percona’s Technical Director – Engineering, on January 25, 2017, at 7 am EST (UTC-8) as he discusses “Percona Server for MySQL 5.7: Key Performance Algorithms.”
In this webinar, Laurynas will discuss selected areas of InnoDB and Percona Server for MySQL 5.7 internals as they relate to buffer pool management and flushing (from a performance and scalability point of view). He will describe the motivation behind the buffer pool mutex split, multi-threaded LRU flusher and parallel doublewrite features in Percona Server for MySQL 5.7, given that MySQL InnoDB 5.7 has re-implemented many of the same features found in Percona Server for MySQL – especially …
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Users had to identify the reasons for MySQL performance problems
somehow well before famous Performance Schema appeared in MySQL 5.5.3,
and even before Domas invented his Poor Man's Profiler. Poor users had
to use some OS-level tools, and among these tools the most
important one was, probably, oprofile.
oprofile is a system-wide statistical profiling tool for Linux
available since 2001 and 2.4.x kernels. It was applied to MySQL
for many …
In this blog, I’ll look at the impact of swapping on MySQL performance.
It’s common sense that when you’re running MySQL (or really any other DBMS) you don’t want to see any I/O in your swap space. Scaling the cache size (using
innodb_buffer_pool_size
in MySQL’s case) is standard practice to make sure there is enough free memory so swapping isn’t needed.
But what if you make some mistake or miscalculation, and swapping happens? How much does it really impact performance? This is exactly what I set out to investigate.
My test system has the following:
To simulate a worst case scenario, I’m using Uniform Sysbench Workload:
sysbench …[Read more]
