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Search Results for: read explain

Getting EXPLAIN information from already running queries in MySQL 5.7

When a new version of MySQL is about to be released we read a lot of blog posts about the performance and scalability improvements. That’s good but sometimes we miss some small features that can …

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Q&A: Multi-threaded Replication in MySQL 5.6 and MySQL 5.7

My webinar “Multi-threaded Replication in MySQL 5.6 and 5.7” on February 25 generated several excellent questions following the presentation (available here for playback along with the slides). I didn’t have time to answer many of the …

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More on MySQL 5.6 multi-threaded replication and GTIDs (and Feb. 25 webinar)

In a previous post, titled “Multi-threaded replication with MySQL 5.6: Use GTIDs,” I explained that using GTID replication is almost a requirement when using MySQL 5.6 MTS. Let’s see now how to perform the day-to-day …

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Hyper-threading – how does it double CPU throughput?

The other day a customer asked me to do capacity planning for their web server farm. I was looking at the CPU graph for one of the web servers that had Hyper-threading switched ON and …

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Explaining Ark Part 4: Fixing Majority Write Concern

This is the fourth post in a series of posts that explains Ark, a consensus algorithm we’ve developed for TokuMX and MongoDB to fix known issues in elections and failover. The tech report we released …

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Explaining Ark Part 3: Why Data May Be Lost on a Failover

This is the third post in a series of posts that explains Ark, a consensus algorithm we’ve developed for TokuMX and MongoDB to fix known issues in elections and failover. The tech report we released …

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Explaining Ark Part 2: How Elections and Failover Currently Work

This is the second post in a series of posts that explains Ark, a consensus algorithm we’ve developed for TokuMX and MongoDB to fix known issues in elections and failover. The tech report we released …

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Explaining Ark Part 1: The Basics

Last week, we introduced Ark, a consensus algorithm similar to Raft and Paxos we’ve developed for TokuMX and MongoDB. The purpose of Ark is to fix known issues in elections and failover. While the tech …

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Percona Toolkit collection: pt-visual-explain

This is the first in a series of posts highlighting a few of the seldom-used but still handy Percona Toolkit tools. Have you ever had a problem understanding the EXPLAIN statement output? And are you …

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Sphinx search performance optimization: multi-threaded search

Queries in MySQL, Sphinx and many other database or search engines are typically single-threaded. That is when you issue a single query on your brand new r910 with 32 CPU cores and 16 disks, the …

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