[cmake-developers] [CMake 0015877]: Performance regression in file generation

[Mantis Bug Tracker]

The following issue has been SUBMITTED. 
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https://cmake.org/Bug/view.php?id=15877 
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Reported By:                Jim King
Assigned To:                
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Project:                    CMake
Issue ID:                   15877
Category:                   CMake
Reproducibility:            always
Severity:                   minor
Priority:                   normal
Status:                     new
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Date Submitted:             2015-12-11 00:50 EST
Last Modified:              2015-12-11 00:50 EST
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Summary:                    Performance regression in file generation
Description: 
There was a significant performance regression between CMake 2.8 and 3.4
between "-- Configuring done" and "--Generating done" phases.  We have a rather
large project with a number of files and here are the timing results:

CMake-3.4

39.27user 10.14system 0:50.62elapsed 97%CPU (0avgtext+0avgdata
119384maxresident)k
40inputs+167408outputs (0major+254266minor)pagefaults 0swaps

CMake-2.8

21.97user 8.09system 0:32.09elapsed 93%CPU (0avgtext+0avgdata
163040maxresident)k
8400inputs+172200outputs (30major+266779minor)pagefaults 0swaps

We're generating on Ubuntu 14.04 LTS with the command:
CC=clang CXX=clang++ time /usr/bin/cmake -G"Eclipse CDT4 - Unix Makefiles"

I could not find a defect for this so I decided to add one.

Steps to Reproduce: 
See description.
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Issue History 
Date Modified    Username       Field                    Change               
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2015-12-11 00:50 Jim King       New Issue                                    
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