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Search Results for: innodb check point

InnoDB checkpoint strikes back

In my recent benchmarks for MongoDB, we can see that the two engines WiredTiger and TokuMX struggle from periodical drops in throughput, which is clearly related to a checkpoint interval – and therefore I correspond …


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 …


The relationship between Innodb Log checkpointing and dirty Buffer pool pages

This is a time-honored topic, and there’s no shortage of articles on the topic on this blog. I wanted to write a post trying to condense and clarify those posts, as it has taken me …


Innodb Fuzzy checkpointing woes

As you might know Innodb storage engines uses Fuzzy Checkpointing technique as part of it recovery strategy.  It is very nice approach which means database never needs to “stall” to perform total modified pages flush …


InnoDB vs TokuDB in LinkBench benchmark

Previously I tested Tokutek’s Fractal Trees (TokuMX & TokuMXse) as MongoDB storage engines – today let’s look into the MySQL area. I am going to use modified LinkBench in a heavy IO-load. I compared InnoDB …


Deep dive into MySQL’s innochecksum tool

One of our Percona Support customers recently reported that Percona XtraBackup failed with a page corruption error on an InnoDB table. The customer thought it was a problem or bug in the Percona XtraBackup tool. …


Looking deeper into InnoDB’s problem with many row versions

A few days ago I wrote about MySQL performance implications of InnoDB isolation modes and I touched briefly upon the bizarre performance regression I found with InnoDB handling a large amount of versions for a single …


InnoDB crash recovery speed in MySQL 5.6

It has been a while since I have looked at InnoDB crash recovery. A lot has change in the last few years – we have serious crash recovery performance improvements in MySQL 5.5 and MySQL …


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 …


When (and how) to move an InnoDB table outside the shared tablespace

In my last post, “A closer look at the MySQL ibdata1 disk space issue and big tables,” I looked at the growing ibdata1 problem under the perspective of having big tables residing inside the so-called shared …