Search Results for: query_cache_size=0

Optimizing MySQL for Zabbix

This blog post was inspired by my visit at the annual Zabbix Conference in Riga, Latvia this year, where I gave a couple of talks on MySQL and beyond. It was a two day single-track event with some 200 participants, a number of interesting talks on Zabbix (and related technologies) and really well-organized evening activities. […]

Percona XtraDB Cluster 5.6.14-25.1 Beta is now available

Percona is glad to announce the first Beta release of Percona XtraDB Cluster 5.6 on November 21st, 2013. Binaries are available from downloads area or from our software repositories. Based on Percona Server 5.6.14-62.0 including all the bug fixes in it, Galera Replicator 3.1 and on Codership wsrep API 5.6.14-25.1 is now the first BETA […]

MySQL and Percona Server in LinkBench benchmark

Around month ago Facebook has announced the Linkbench benchmark that models the social graph OLTP workload. Sources, along with a very nice description of how to setup and run this benchmark, can be found here. We decided to run this benchmark for MySQL Server 5.5.30, 5.6.11 and Percona Server 5.5.30 and check how these servers […]

A case for MariaDB’s Hash Joins

MariaDB 5.3/5.5 has introduced a new join type “Hash Joins” which is an implementation of a Classic Block-based Hash Join Algorithm. In this post we will see what the Hash Join is, how it works and for what types of queries would it be the right choice. I will show the results of executing benchmarks […]

MySQL 5.5.8 and Percona Server: being adaptive

As we can see, MySQL 5.5.8 comes with great improvements and scalability fixes. Adding up all the new features, you have a great release. However, there is one area I want to touch on in this post. At Percona, we consider it important not only to have the best peak performance, but also stable and predictable performance. I refer you […]

Tuning InnoDB Concurrency Tickets

InnoDB has an oft-unused parameter innodb_concurrency_tickets that seems widely misunderstood. From the docs: “The number of threads that can enter InnoDB concurrently is determined by the innodb_thread_concurrency variable. A thread is placed in a queue when it tries to enter InnoDB if the number of threads has already reached the concurrency limit. When a thread […]

Another scalability fix in XtraDB

Recent scalability fixes in InnoDB and also Google’s and your SMP fixes almost made InnoDB results acceptable in primary key lookups queries, but secondary indexes were forgotten for some time. Now having Dell PowerEdge R900 on board (16CPU cores, 16GB RAM) I have some time for experiments, and I played with queries

Fix of InnoDB/XtraDB scalability of rollback segment

Recently I wrote about InnoDB scalability on 24-core box, and we made research of scalability problems in sysbench write workload (benchmark emulates intensive insert/delete queries). By our results the problem is in concurrency on rollback segment, which by default is single and all transactions are serialized accessing to segment. Fortunately InnoDB internally has mechanism to […]