On 4/24/05, Peter Dimov <pdimov@mmltd.net> wrote:
What are the design goals of read_write_mutex? (Lock proliferation aside for a moment.)
Attached is a copy of the test program modified to use the ACE library and to use n_writers = 1. Performance of the two cases is much closer, though the read-write case still suffers compared to the simple mutex case and is really platform-dependant. Here are my results (where rwlock-ace is the simple case and rwlock-ace-rw is the read/write case): Linux/g++: ./rwlock-ace 3.90s user 14.54s system 326% cpu 5.648 total ./rwlock-ace-rw 6.94s user 26.57s system 226% cpu 14.776 total Solaris/Sun C++: ./rwlock-ace-sun 7.64s user 50.66s system 691% cpu 8.427 total ./rwlock-ace-sun-rw 34.19s user 250.70s system 465% cpu 1:01.18 total I'd say the design of the Boost.Threads read/write mutex is sub-optimal compared to the one on ACE. -- Caleb Epstein caleb dot epstein at gmail dot com