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Search Results for: write buffers

MySQL 5.6 vs MySQL 5.5 and the Star Schema Benchmark

So far most of the benchmarks posted about MySQL 5.6 use the sysbench OLTP workload.  I wanted to test a set of queries which, unlike sysbench, utilize joins.  I also wanted an easily reproducible set …


Concurrency Improvements in TokuDB v6.6 (Part 2)

In Part 1, we showed performance results of some of the work that’s gone in to TokuDB v6.6. In this post, we’ll take a closer look at how this happened, on the engineering side, and …


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 …


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 …


Choosing an appropriate benchmark length

The duration of a benchmark is an important factor that helps determine how meaningful it is. Most systems have some “burstable capacity,” and this can influence the results a lot. You can see this in …


High Rate insertion with MySQL and Innodb

I again work with the system which needs high insertion rate for data which generally fits in memory. Last time I worked with similar system it used MyISAM and the system was built using multiple …


How long Innodb Shutdown may take

How long it may take MySQL with Innodb tables to shut down ? It can be quite a while. In default configuration innodb_fast_shutdown=ON the main job Innodb has to do to complete shutdown is flushing …


On Benchmarks on SSD

(cross post from SSD Performance Blog ) To get meaningful performance results on SSD storage is not easy task, let’s see why. There is graph from sysbench fileio random write benchmark with 4 threads. The …


How is join_buffer_size allocated?

When examining MySQL configuration, we quite often want to know how various buffer sizes are used. This matters because some buffers (sort_buffer_size for example) are allocated to their full size immediately as soon as they …


table_cache negative scalability

Couple of months ago there was a post by FreshBooks on getting great performance improvements by lowering table_cache variable. So I decided to investigate what is really happening here. The “common sense” approach to tuning …