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Search Results for: do the math

Just do the math!

One of the most typical reasons for performance and scalability problems I encounter is simply failing to do the math. And these are typically bad one because it often leads to implementing architectures which are …

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The Math of Automated Failover

There are number of people recently blogging about MySQL automated failover, based on production incident which GitHub disclosed. Here is my take on it. When we look at systems providing high availability we can identify …

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Don’t Thrash: How to Cache your Hash on Flash

Last week I gave a talk entitled “Don’t Thrash: How to Cache your Hash.” The talk took place at the Workshop on Algorithms and Data Structures (ADS) in a medieval castle turned conference center in …

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How much space does empty Innodb table take ?

How much space would empty MyISAM table take ? Probably 8K for .frm file, 1KB for .MYI file and 0 for MYD file. .MYI file can be larger if you have many indexes. How much …

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The MySQL optimizer, the OS cache, and sequential versus random I/O

In my post on estimating query completion time, I wrote about how I measured the performance on a join between a few tables in a typical star schema data warehousing scenario. In short, a query …

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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 …

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Optimizing MySQL for Zabbix

This blog post was inspired by my visit at the annual Zabbix Conference in Riga, Latvia this year, where I gave a couple of talks on MySQL and beyond. It was a two day single-track …

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Edge-case behavior of INSERT…ODKU

A few weeks back, I was working on a customer issue wherein they were observing database performance that dropped through the floor (to the point of an outage) roughly every 4 weeks or so. Nothing …

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Rendundant Array of Inexpensive Servers

So you need to design highly available MySQL powered system… how do you approach that ? Too often I see the question is approached by focusing on expensive hardware which in theory should be reliable. …

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How to estimate query completion time in MySQL

Have you ever run a query in MySQL and wondered how long it’ll take to complete? Many people have had this experience. It’s not a big deal until the query has been running for an …

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