On 2016-11-23, Philippe Meunier <meun...@ccs.neu.edu> wrote: > Does anyone know of a relatively common program for which S > is a human-noticeable performance hit?
vim with syntax highlighting. As a simple example just opening a file, the visible effect is a small extra delay, and easy to time: $ time (for i in `jot 10`; do vim '+:q!' /usr/ports/infrastructure/mk/bsd.port.mk; done) 0m00.45s real 0m00.34s user 0m00.11s system $ time (for i in `jot 10`; do MALLOC_OPTIONS=S vim '+:q!' /usr/ports/infrastructure/mk/bsd.port.mk; done) 0m01.27s real 0m00.40s user 0m00.85s system For interactive use, deleting lines in such a file (causing it to re-highlight as it goes) becomes very painful.