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-p option report much less time than actual on high intensity of FFI calls application

Proprietary application is ran on 44 cores (88 with HT) machine (same problem on 12 core). It is Haskell between wxHaskell (wxWidgets for UI) and C API. It is doing FFI calls most of the time. Calls are not so many, but possibly not so fast. I'm trying to profile where is the problem, in which calls. But very strange behaviour is there. "total time" of application that is running 30secs to 1min is showing 0.33secs. Even MAIN function is not 100%.

Please, see first part of .prof file:

 Tue Mar 28 15:38 2017 Time and Allocation Profiling Report (Final)

 app.exe +RTS -N -A40m -qb0 -p -RTS

 total time = 0.33 secs (325 ticks @ 1000 us, 1 processor)
 total alloc = 86,317,264 bytes (excludes profiling overheads)

COST CENTRE MODULE SRC %time %alloc

MAIN MAIN <built-in> 12.6 2.2
Trac metadata
Trac field Value
Version 8.0.2
Type Bug
TypeOfFailure OtherFailure
Priority normal
Resolution Unresolved
Component Profiling
Test case
Differential revisions
BlockedBy
Related
Blocking
CC
Operating system
Architecture
Edited by adam
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