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Search Results for: percentile

Color code your performance numbers

When analyzing how good or bad response time is it is not handy to look at the averages, min or max times – something what is easily computed using built in aggregate functions. We most …

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Tuning InnoDB Concurrency Tickets

InnoDB has an oft-unused parameter innodb_concurrency_tickets that seems widely misunderstood. From the docs: “The number of threads that can enter InnoDB concurrently is determined by the innodb_thread_concurrency variable. A thread is placed in a queue …

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What do we optimize with mk-query-digest ?

When we’re looking at mk-query-digest report we typically look at the Queries causing the most impact (sum of the query execution times) as well as queries having some longest samples. Why are we looking at …

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mysql-proxy, urgh performance and scalability ?

For one our project I needed proxy solution, and mysql-proxy is one of well-known, so it was logical first choice. The obvious question which come in mind is what performance penalty we have using mysql-proxy, …

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Understanding Performance Optimization Terminology

There are few terms you need to have a good understanding if you’re working with high volume systems. I commonly see these mixed and people not understanding the difference between them. Performance – The performance …

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Goal driven performance optimization

When your goal is to optimize application performance it is very important to understand what goal do you really have. If you do not have a good understanding of the goal your performance optimization effort …

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Evaluating IO subsystem performance for MySQL Needs

I’m often asked how one can evaluate IO subsystem (Hard drive RAID or SAN) performance for MySQL needs so I’ve decided to write some simple steps you can take to get a good feeling about …

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