Read mmap limitations

Originator:mk
Number:rdar://17092823 Date Originated:02-Jun-2014
Status:No Value Resolved:
Product:iOS SDK Product Version:iOS 7.1
Classification: Reproducible:
 
According to the Apple documentation (https://developer.apple.com/library/mac/documentation/performance/conceptual/managingmemory/articles/aboutmemory.html) there should be no limit to the size of read-only files, as pages should be paged out accordingly.

Steps to Reproduce:
1. Open the Xcode project in this GitHub repo: https://github.com/mekjaer/ios-mmap
2. Tweak the parameters in AppDelegate.m - line 19
3. Run example on different iOS devices

Expected Results:
No limit to the size of the read-only mmap'ed files

Actual Results:
Depending on the number of files and device the maximum size for a real-only mmap'ed file is between 300mb to 1900mb.

Comments


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