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Search Results for: double buffer

Update on the InnoDB double-write buffer and EXT4 transactions

In a post, written a few months ago, I found that using EXT4 transactions with the “data=journal” mount option, improves the write performance significantly, by 55%, without putting data at risk. Many people commented on …


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 …


Some little known facts about Innodb Insert Buffer

Despite being standard Innodb feature forever Insert Buffers remains some kind of mysterious thing for a lot of people, so let me try to explain thing a little bit. Innodb uses insert buffer to “cheat” …


Choosing innodb_buffer_pool_size

My last post about Innodb Performance Optimization got a lot of comments choosing proper innodb_buffer_pool_size and indeed I oversimplified things a bit too much, so let me write a bit better description. Innodb Buffer Pool …


Innodb Double Write

One of very interesting techniques Innodb uses is technique called “doublewrite” It means Innodb will write data twice when it performs table space writes – writes to log files are done only once. So why …


InnoDB performance optimization basics (redux)

I recently stumbled upon a post that Peter Zaitsev published back in 2007 titled “Innodb Performance Optimization Basics.” It’s a great post and reading it inspired me to examine what’s changed in the nearly six …


Is there room for more MySQL IO Optimization?

I prefer to run MySQL with innodb_flush_method=O_DIRECT in most cases – it makes sure there is no overhead of double buffering and I can save the limited amount of file system cache I would normally …


xtrabackup-0.7 (RC)

We announce next version of our xtrabackup tool and we consider it stable enough to put label RC on it. Changelist includes: – use O_DIRECT by default for handling InnoDB files – use posix fadvise …


The tool I’ve been waiting for years

I’ve just been pointed to the nice tool which I was waiting for years to see. It is fincore – little perl script which allows you to see what pages of file are cached in …


Heikki Tuuri answers to Innodb questions, Part II

I now got answers to the second portions of the questions you asked Heikki. If you have not seen the first part it can be found here. Same as during last time I will provide …