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Tag: percona-toolkit

  • Continuous feedback from jenkins console output

    This one really was a pain in the ass for a long time.

    Jenkins is great, not only for building projects, but I start the most of the ops related tasks here. All the projects have their own workspace, I can browse the previous outputs, see if a task failed or not, and I can easily share the results at the end of the task.

    I had only one problem with that: the long-running tasks weren’t shown on console output until they finished. I tried to solve that, but it was only annoying, not a showstopper, so I let that go, because it didn’t look like an easy win, and I didn’t want to spend too much time on that.

    But last week I created a job for online altering the database and – surprise! – pt-online-schema-change was continuously updated the console log screen, so I started to google out what is happening.

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  • A few words about database checksumming

    MySQL replication is great, and kind of reliable, but sometimes it could be messed up. The good news is that we can handle this.

    Let’s see how replication happens when everything is fine!

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  • Syncing differences in MySQL cluster

    In my last post, I showed how to fix replication errors on slaves, but I’ve made a mistake: my current example wasn’t good, after skipping the command or inserting an empty transaction the dataset was different because of a timestamp holding date column which is the CURRENT_TIMESTAMP default. Fixing the error solved the problem of the running replication thread, but the data wasn’t same on the hosts. I decided to leave this as-is, and instead of recreating the test, I rather show how to sync the databases.

    For this, we can use the ‘pt-table-checksum’ and ‘pt-table-sync’ utilities from Percona toolkit.

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