Measuring ElectricAccelerator Cache Efficiency

Somebody asked me the other day, “How much does the ElectricAccelerator filesystem cache reduce I/O load on my build host?” This is an interesting question, because in some cases, the impact of Accelerator caching is a big part of the performance benefit. Consider the case of ClearCase dynamic views, which have notoriously bad performance, particularly for stat() operations. By reducing the number of times the build accesses the host filesystem, Accelerator can provide a substantial performance boost. In one extreme case, I saw a build that ran 50 times faster just by using a single Accelerator agent, because the the host filesystem was so slow. In this post, I’ll show how you how to determine how much Accelerator caching is doing for your build.
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ElectricAccelerator Agent Metrics, part 2

ElectricAccelerator agent metrics provide a tremendous amount of data that you can use to analyze and improve the performance of your builds. Last time we saw how to collect the metrics and we explored the data presented in the Overall time usage section. This time, we’ll look at the data in the Usage records section.

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ElectricAccelerator Agent Metrics, part 1

Welcome to the Electric Cloud Blog! My name is Eric Melski, and I’m a Senior Software Engineer at Electric Cloud (employee #1, by a whisker). I’ve worked on every component of ElectricAccelerator, and I’m now Technical Lead for the product. I’m also the guy behind ElectricInsight. In this and future posts, I will take you on deep technical dives into Accelerator and Insight, with a focus on performance, scalability and analysis.

Understanding the performance of parallel, distributed systems can be difficult. Fortunately, Accelerator provides a wealth of data to facilitate performance analysis. In this first continuation of my presentation at the 2008 Customer Summit, I’ll show you how to collect agent performance metrics, and how you can use them to get a quick overview of the performance characteristics of your build.

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