Emergency

Author Archives: Aurimas Mikalauskas

Aligning IO on a hard disk RAID – the Benchmarks

In the first part of this article I have showed how I align IO, now I want to share results of the benchmark that I have been running to see how much benefit can we …

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Aligning IO on a hard disk RAID – the Theory

Now that flash storage is becoming more popular, IO alignment question keeps popping up more often than it used to when all we had were rotating hard disk drives. I think the reason is very …

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Aspersa tools bit.ly download shortcuts

I use Aspersa tools a lot and I find myself going to the website just to download one of the tools all the time. I love I can download maatkit with a simple wget maatkit.org/get/tool …

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Optimizing slow web pages with mk-query-digest

I don’t use many tools in my consulting practice but for the ones I do, I try to know them as best as I can. I’ve been using mk-query-digest for almost as long as it …

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Maatkit’s mk-query-digest filters

Have you ever seen BIG weird numbers in mk-query-digest report that just seem wrong? I have! Here’s one report I got today:

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Lost innodb tables, xfs and binary grep

Before I start a story about the data recovery case I worked on yesterday, here’s a quick tip – having a database backup does not mean you can restore from it. Always verify your backup …

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UDF -vs- MySQL Stored Function

Few days ago I was working on a case where we needed to modify a lot of data before pushing it to sphinx – MySQL did not have a function to do the thing so …

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Too many connections? No problem!

Did that ever happen to you in production?

Just happened to one of our customers. Want to know what we did?

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Profiling MySQL stored routines

These days I’m working with a customer who has an application based entirely on stored routines on MySQL side. Even though I haven’t worked much with stored procedures, I though it’s going to be a …

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Using MMM to ALTER huge tables

Few months ago, I wrote about a faster way to do certain table modifications online. It works well when all you want is to remove auto_increment or change ENUM values. When it comes to changes …

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