Switching tabs in Xcode is slow after period of use

Originator:annglove
Number:rdar://12392475 Date Originated:27-Sep-2012 09:12 PM
Status:Open Resolved:
Product:Xcode Product Version:4.5
Classification:Performance Reproducible:YES
 
27-Sep-2012 09:12 PM Evan Long:
Summary:
After using Xcode for 10-30 minutes tab switching is very slow

Steps to Reproduce:
1. Open 3-5 tabs in Xcode. Keep these tabs open and work for about 10-30 minutes (possibly less time).
2. Periodically switch tabs. Notice the time to switch might take about 1 second of time.

Expected Results:
Switching tabs should be very fast.

Actual Results:
Switching tabs is very slow. 

Regression:
This appears to be a regression since 4.4.1.

Notes:
Restarting Xcode fixes the issue. Tab switching is fast again.

Other users appear to have similar issues and have posted to Stack Overflow: http://stackoverflow.com/questions/12624391/very-slow-tab-switching-in-xcode-4-5-mountain-lion

I have attached a sample collected with Activity Monitor and it appears that a good chunk of time is spent on the main thread in `selectTabViewItem:` which makes sense. 

I have disabled antialiased font rendering. So that I can use Courier New.

27-Sep-2012 09:12 PM Evan Long:
'slow_tab.txt' was successfully uploaded

Comments


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