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Displaying posts with tag: gh-ost (reset)
This Week in Data with Colin Charles 41: Reflecting on GitHub’s Contribution to Open Source Database

Join Percona Chief Evangelist Colin Charles as he covers happenings, gives pointers and provides musings on the open source database community.

Some big news out from Microsoft about their acquisition of GitHub for $7.5 billion. GitHub hosts many projects, including from the MySQL ecosystem, but maybe more interesting is that their DBA team is awesome, give great talks, and are generally prolific writers. Some of the cool tools the MySQL world has gotten thanks to the excellent team include (but are not limited to): ccql, gh-ost for triggerless online schema migrations, and Orchestrator which is a GUI-based High Availability and …

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On InnoDB's Online DDL

I am completing my preparations for the upcoming FOSDEM talk, and one of last things I wanted to do in frames of them is a quick review of known bugs and problems in current (as in MySQL 5.7 GA) implementation of so called "online" DDL for InnoDB tables.

In my previous post I already shared my view on another important InnoDB feature, persistent statistics. Unlike that, I do not really hate online DDL. I just try to avoid it if possible and use tools like pt-online-schema-change or gh-ost instead. Not because it is not documented properly (the …

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gh-ost hooks for better visibility

In this post I will show you how to leverage Github’s gh-ost hooks for greatly improving visibility of ongoing schema changes for your organization.

One of the potential uses of gh-ost hooks is to send status updates. I will present you with some examples of how to do that via email and Slack.

What are gh-ost hooks?

gh-ost has built-in support for hooks, i.e. external scripts with predefined names, that will be called by gh-ost at certain points of a schema change operation.

The complete list is available here, but the most useful gh-ost hooks for me are:

  • gh-ost-on-startup-hook
    • called at the start of a schema change operation
  • gh-ost-on-status-hook
    • ran …
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Gh-ost benchmark against pt-online-schema-change performance

In this blog post, I will run a gh-ost benchmark against the performance of pt-online-schema-change.

When gh-ost came out, I was very excited. As MySQL ROW replication became commonplace, you could use it to track changes instead of triggers. This practice is cleaner and safer compared to Percona Toolkit’s pt-online-schema-change. Since gh-ost doesn’t need triggers, I assumed it would generate lower overhead and work faster. I frequently called it “pt-online-schema-change on steroids” in my talks. …

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Showing entries 1 to 4