ffmpeg performance on OSX

[monochromec]

Summary of the bug: eliminating a track from an MKV container on 10.14.2 (model 14,2 16 GB main memory) takes two hours vs. five minutes on an Armada XP (32 ARM v7). Video file is approx. 2.5 GB.
How to reproduce:

%  ffmpeg -i in.mkv -map 0 -map -1:a:0 out.mkv
ffmpeg version: Installed via homebrew

ffmpeg version 4.1 Copyright (c) 2000-2018 the FFmpeg developers
  built with Apple LLVM version 10.0.0 (clang-1000.11.45.5)
  configuration: --prefix=/usr/local/Cellar/ffmpeg/4.1 --enable-shared --enable-pthreads --enable-version3 --enable-hardcoded-tables --enable-avresample --cc=clang --host-cflags= --host-ldflags= --enable-ffplay --enable-gpl --enable-libmp3lame --enable-libopus --enable-libsnappy --enable-libtheora --enable-libvorbis --enable-libvpx --enable-libx264 --enable-libx265 --enable-libxvid --enable-lzma --enable-opencl --enable-videotoolbox
  libavutil      56. 22.100 / 56. 22.100
  libavcodec     58. 35.100 / 58. 35.100
  libavformat    58. 20.100 / 58. 20.100
  libavdevice    58.  5.100 / 58.  5.100
  libavfilter     7. 40.101 /  7. 40.101
  libavresample   4.  0.  0 /  4.  0.  0
  libswscale      5.  3.100 /  5.  3.100
  libswresample   3.  3.100 /  3.  3.100
  libpostproc    55.  3.100 / 55.  3.100

More than happy to provide more info as required - please let me know if this should go to homebrew instead but I suspect a more generic issue in code base.

[Elon Musk]

you are transcoding, you nowhere use -c copy in above command.

[monochromec]

Good catch - let's close the ticket.