I'm trying to profile app startup after moving from static libraries to frameworks. We have 30 or so frameworks (fyi: cocoapods) so I want to check that it's not affecting performance. Anecdotal testing in the team says that it isn't, but I would like some numbers as well!
I've added the environment variables DYLD_PRINT_STATISTICS and DYLD_PRINT_LIBRARIES to see what the linker is doing, but all the output I get is from the DYLD_PRINT_LIBRARIES variable. I can see that the frameworks are loading correctly, but get no statistics from them.
I've tried restarting the device to make sure that the frameworks aren't in memory already but that hasn't helped.
Any other suggestions as to why I'm not getting any output from DYLD_PRINT_STATISTICS?
While other flags, like DYLD_PRINT_BINDINGS work fine on the device, DYLD_PRINT_STATISTICS only seems to work on the simulator (for me, iOS 9.0).
In this (possibly unrelated) version of dyld.cpp, from osx 10.10.5 there doesn't seem to be any obvious exclusion of DYLD_PRINT_STATISTICS for devices, although there are conditionally compiled TARGET_IPHONE_SIMULATORs sprinkled throughout the code.
I guess it's a bug.
Looks like you can do it on device if you enable both environment variables in your scheme:
DYLD_PRINT_APIS = YES
DYLD_PRINT_STATISTICS = YES
Reference: https://github.com/artsy/eigen/issues/586#issuecomment-118606377
来源：https://stackoverflow.com/questions/33776715/dyld-print-statistics-not-showing-anything