November 23, 2014

Innodb redo log archiving

Percona Server 5.6.11-60.3 introduces a new “log archiving” feature. Percona XtraBackup 2.1.5 supports “apply archived logs.” What does it mean and how it can be used? Percona products propose three kinds of incremental backups. The first is full scan of data files and comparison the data with backup data to find some delta. This approach […]

Measuring the amount of writes in InnoDB redo logs

Choosing a good InnoDB log file size is key to InnoDB write performance. This can be done by measuring the amount of writes in the redo logs. You can find a detailed explanation in this post. To sum up, here are the main points: The redo logs should be large enough to store at most […]

How InnoDB handles REDO logging

Xaprb (Baron) recently blogged about how InnoDB performs a checkpoint , I thought it might be useful to explain another important mechanism that affects both response time and throughput – The transaction log.

MySQL’s INNODB_METRICS table: How much is the overhead?

Starting with MySQL 5.6 there is an INNODB_METRICS table available in INFORMATION_SCHEMA which contains some additional information than provided in the SHOW GLOBAL STATUS output – yet might be more lightweight than PERFORMANCE_SCHEMA. Too bad INNODB_METRICS was designed during the Oracle-Sun split under MySQL leadership and so it covers only InnoDB counters. I think this […]

How to improve InnoDB performance by 55% for write-bound loads

During April’s Percona Live MySQL Conference and Expo 2014, I attended a talk on MySQL 5.7 performance an scalability given by Dimitri Kravtchuk, the Oracle MySQL benchmark specialist. He mentioned at some point that the InnoDB double write buffer was a real performance killer. For the ones that don’t know what the innodb double write […]

Engineer duo from Google, LinkedIn join again for InnoDB talks

Google senior systems engineer Jeremy Cole is once again teaming with LinkedIn senior software engineer Davi Arnaut for two InnoDB-focused sessions at the upcoming Percona Live MySQL Conference and Expo 2014 this April 1-4 in Santa Clara, California. The duo will present “InnoDB: A journey to the core II” on April 2 and “InnoDB: A […]

Incremental backups with log archiving for XtraDB

Percona Server 5.6.11-60.3 has introduced a new feature called Log Archiving for XtraDB. This feature makes copies of the old log files before they are overwritten, thus saving all the redo log for a write workload. When log archiving is enabled, it duplicates all redo log writes in a separate set of files in addition […]

InnoDB adaptive flushing in MySQL 5.6: checkpoint age and io capacity

In MySQL 5.6 InnoDB has a dedicated thread (page_cleaner) that’s responsible for performing flushing operations. Page_cleaner performs flushing of the dirty pages from the buffer pool based on two factors: – access pattern  –  the least recently used pages will be flushed by LRU flusher from LRU_list when buffer pool has no free pages anymore; […]

How to move the InnoDB log sequence number (LSN) forward

This post focuses on the problem of the InnoDB log sequence number being in the future. Preface: What is an InnoDB log sequence number? The Log sequence number (LSN) is an important database parameter used by InnoDB in many places. The most important use is for crash recovery and buffer pool purge control. Internally, the InnoDB […]

MySQL 5.6 – InnoDB Memcached Plugin as a caching layer

A common practice to offload traffic from MySQL 5.6 is to use a caching layer to store expensive result sets or objects.  Some typical use cases include: Complicated query result set (search results, recent users, recent posts, etc) Full page output (relatively static pages) Full objects (user or cart object built from several queries) Infrequently […]