Upload
vinson
View
36
Download
0
Embed Size (px)
DESCRIPTION
Diagnosing performance and memory issues in JavaScript-based Windows Store Apps. Andrew Hall Program Manager II 3-008. The performance of an app will determine whether customers are willing to continue using your app, so make it great. Agenda. Good Performance Practices - PowerPoint PPT Presentation
Citation preview
Diagnosing performance and memory issues in JavaScript-based Windows Store AppsAndrew HallProgram Manager II3-008
The performance of an app will determine whether customers are willing to continue
using your app, so make it great
Good Performance PracticesVisual Studio Profiler BasicsHTML5 Performance AnalyzerJavaScript Memory Profiler Basics
Agenda
Good performance practicesBe responsive, don’t block the UI thread• Users notice delays of more than 100ms• Break up longer operations or use web workers
Monitor your app’s memory use• The smaller your footprint the less likely the OS
will terminate your app while suspendedTune your apps performance regularly
Visual Studio JavaScript profilerInstrumentation-based profiling• Records how long every method takes to execute• Records exact counts of method calls
Only shows JavaScript execution time• Does not show work done by other systems (e.g., rendering or layout)
Profiler terminologyInclusive time: The total amount of time from when the function was entered until the function exited• Includes the total time spent in all child functions
Exclusive time: The amount of time spent executing code in just the function body• Does NOT include time spent in child functions
function Alpha(){
Beta();}function Beta(){
}
Inclusive and exclusive time
30 ms
50 ms
Exclusive Inclusive
Alpha
Beta 50 50
30 80
Demo
Performance Analyzer for HTML5 AppsWalks you through testing your applicationGenerates a report measuring 13 tenets of performanceInstalls with the SDKActivation time Memory leaks
UI responsiveness Idle state CPU usageLayout passes Successful suspendSynchronous XMLHttpRequest on UI thread
Memory reduction when suspended
Image scaling App memory growthMemory footprint Runtime broker memory growthRuntime broker memory reference set
Demo
JavaScript Memory ProfilerIdentify unintentionally retained memoryand inefficient use of memorySnapshot-based toolShows JavaScript and DOM elements• Size• Counts• Reference graph
Memory terminologySize: How large the object is in memoryRetained Size: The amount of memory that the object is preventing the garbage collector from reclaiming• Includes the size of the object• Includes the size of all referenced objects (and any objects they
reference) that the current object is the only parent of in the memory graph
Size and retained size
Size Retained SizeObject AObject BObject CObject D
500 KB 500 KB100 KB 600 KB
Object A (100 KB)
Object B (500 KB)
Object C (50 KB)
Object D (100 KB)
50 KB100 KB
50 KB100 KB
Object A (100 KB)
Object B (500 KB)
600 KB
Demo
SummaryInstall the Visual Studio Quarterly Update #1Use the tools you already have to improvethe performance of your app• Visual Studio JavaScript Profiler• Visual Studio JavaScript Memory Profiler• HTML5 Performance Analyzer
Questions?
Related Sessions[4-000] Building High-Performing JavaScript for Modern Engines[3-014] Modern JavaScript
Tools• HTML5 Performance Analyzer:
http://msdn.microsoft.com/en-us/library/windows/apps/jj553524.aspx
• Visual Studio Profiler: http://msdn.microsoft.com/en-us/windows/apps/hh696637.aspx
• JavaScript Memory Analyzer: http://msdn.microsoft.com/en-us/library/windows/apps/jj819177.aspx
Performance Guidance• http://msdn.microsoft.com/en-us/library/windows/apps
/jj553524.aspx• http://channel9.msdn.com/Events/Build/BUILD2011/AP
P-162T
Resources
Please submit session evals on the Build Windows 8 App or at http://aka.ms/BuildSessions
© 2012 Microsoft Corporation. All rights reserved. Microsoft, Windows, Windows Vista and other product names are or may be registered trademarks and/or trademarks in the U.S. and/or other countries.The information herein is for informational purposes only and represents the current view of Microsoft Corporation as of the date of this presentation. Because Microsoft must respond to changing market conditions, it should not be interpreted to be a commitment on the part of Microsoft, and Microsoft cannot guarantee the accuracy of any information provided after the date of this presentation. MICROSOFT MAKES NO WARRANTIES, EXPRESS, IMPLIED OR STATUTORY, AS TO THE INFORMATION IN THIS PRESENTATION.