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Search Results for: bbu flush log

Do not trust vmstat IOwait numbers

I’ve been running a benchmark today on my old test box with conventional hard drives (no raid with BBU) and noticed something unusual in the CPU utilization statistics being reported. The benchmark was run like …


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 …


Looking for RAID Controller without Battery Learning problems ?

A lot have been written about Battery Learning Cycle problems and its impact to MySQL Performance. Here are couple of links (1,2). It is good to see though there are some controllers coming out which …


Aligning IO on a hard disk RAID – the Benchmarks

In the first part of this article I have showed how I align IO, now I want to share results of the benchmark that I have been running to see how much benefit can we …


Battery Learning still problem many years after

The performance problems caused by battery auto learning go many years back. We wrote about it, other people from MySQL Community too. The situation did not get better, at least not with Dell RAID controllers, …


Maximal write througput in MySQL

I recently was asked what maximal amount transactions per second we can get using MySQL and XtraDB / InnoDB storage engine if we have high-end server. Good questions, though not easy to answer, as it …


When would you use SAN with MySQL ?

One question which comes up very often is when one should use SAN with MySQL, which is especially popular among people got used to Oracle or other Enterprise database systems which are quite commonly deployed …


Disaster: LVM Performance in Snapshot Mode

In many cases I speculate how things should work based on what they do and in number of cases this lead me forming too good impression about technology and when running in completely unanticipated bug …


Linux schedulers in tpcc like benchmark

I mentioned earlier that IO scheduler CFQ coming by default in RedHat / CentOS 5.x may be not so good for MySQL. And yesterday one customer reported that just changing cfq to noop solved their …


XtraDB in CPU-bound benchmark

Peter said me that previous results https://www.percona.com/blog/2008/12/18/xtradb-benchmarks-15x-gain/ are too marketing, and we should show other results also. Here is the run for CPU Bound,or it would be more correctly to say in-cache benchmark, because there …