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New distribution of random generator for sysbench – Zipf

Sysbench has three distribution for random numbers: uniform, special and gaussian. I mostly use uniform and special, and I feel that both do not fully reflect my needs when I run benchmarks. Uniform is stupidly …

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FusionIO 320GB MLC random write performance

I was advised that new drivers and new firmware for FusionIO cards improve performance and stability and it is recommended to review results I’ve got about year ago. Using the same methodology and the same …

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MySQL Quality Assurance: A Vision for the Future by Roel Van de Paar (Final Episode 13)

Welcome to the final – but most important – episode in the MySQL QA Series. In it, I present my vision for all MySQL Quality Assurance – for all distributions – worldwide. Episode 13: A Better …

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Innodb transaction history often hides dangerous ‘debt’

In many write-intensive workloads Innodb/XtraDB storage engines you may see hidden and dangerous “debt” being accumulated – unpurged transaction “history” which if not kept in check over time will cause serve performance regression or will …

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Reducer.sh – A powerful MySQL test-case simplification/reducer tool

Let me start by saying a big “thank you” to the staff at Oracle for deciding to open source reducer.sh. It’s a tool I developed whilst I was working for them several years ago. Its …

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Why a Partitioned Collection Cannot Be Sharded

In TokuMX 1.5, we introduced partitioned collections for non-sharded clusters. That is, one can have a partitioned collection in a replica set, but one cannot shard a partitioned collection. In this post, I explain why. …

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Why %util number from iostat is meaningless for MySQL capacity planning

Earlier this month I wrote about vmstat iowait cpu numbers and some of the comments I got were advertising the use of util% as reported by the iostat tool instead. I find this number even more useless for …

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The Difference Between TokuMX Partitioning and Sharding

In my last post, I described a new feature in TokuMX 1.5—partitioned collections—that’s aimed at making it easier and faster to work with time series data. Feedback from that post made me realize that some …

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Location for InnoDB tablespace in MySQL 5.6.6

There is one new feature in MySQL 5.6 that didn’t get the attention it deserved (at least from me 😉 ) : “DATA DIRECTORY” for InnoDB tables. This is implemented since MySQL 5.6.6 and can …

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ScaleArc: Real-world application testing with WordPress (benchmark test)

ScaleArc recently hired Percona to perform various tests on its database traffic management product. This post is the outcome of the benchmarks carried out by me and ScaleArc co-founder and chief architect, Uday Sawant. The …

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