Main Thread Task Execution, Private Single Page Test Results and More

Karolina Szczur

Karolina Szczur

December 12, 2019

Release Notes is a monthly summary of new features and product improvements.

Inspect blocking scripts with Main thread task execution timeline

JavaScript task execution is the source of the biggest and most common performance bottlenecks. Avoiding long-running tasks and blocking the JavaScript main thread is one of the most critical performance strategies to employ, but discovering problematic scripts is difficult.

The Main thread execution timeline that can be found in Snapshot Overview, brings transparency to what’s happening on the main thread. You will be able to see the distinction between rendering and execution phases with Style and Layout, Script Evaluation and Script Parsing and Compilation.

You can inspect how long each process blocked the main thread for and which script is to blame. Analysing main thread activity just became much easier.

Set Single Page Test results to private

Historically, Single Page Tests results pages were always set to public so you could easily share it with your team, even if they don’t have a Calibre account.

Now, you can set your Single Page Tests results to be private through both the CLI and Node.js API. Private results can only be accessed after logging into Calibre.

To run a private Single Page Test, add --private flag in the CLI:

1calibre create test --location=Sydney --private

More options for filtering metric charts

When browsing specific metric data, you can filter charts by 6 months, 3 months, 1 month and 7 days intervals to drill down into performance regressions and improvements more efficiently.

Advanced filtering becomes especially helpful when you run tests frequently and tag deployments on your charts.

Order Test Profiles

In October, we launched reordering Pages. Similarly, now you’re able to arrange Test Profiles.

If you change the position of Test Profiles in Settings → Test Profiles, they will appear in that order on your metric charts and Insights email reports. The first profile will also become your default profile while viewing Snapshots and the order.

New documentation: Getting Started and Pull Request Reviews

If you ever wondered how to make the most of our performance platform, we wrote a Getting Started Guide. It walks through enabling core features to successfully set up a comprehensive monitoring system.

Pull Request Reviews is currently in private beta, but we already documented how to connect Calibre to your GitHub repositories to enable performance tracking on work-in-progress.

Karolina Szczur

Karolina Szczur

Karolina is the Product Design Lead at Calibre. With years of design experience under her belt, she’s responsible for the comprehensive user experience spanning over product, visuals and content. Find her on Twitter or LinkedIn.


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