Bob Friesenhahn wrote: > On Fri, 10 Jul 2009, Roland Mainz wrote: > >> Some applications may misbehave or lock-up if the size of the pipe > >> buffer is changed. > > > > Erm... why ? > > You have already noticed that the size is hard-coded in Solaris > applications (by PIPE_BUF) since the dawn of time. Pipes offer > properties such as atomic reads and writes. PIPE_BUF declares the > maximum size of an atomic write. Some applications depend on this > FIFO behavior for message passing.
Erm... what will happen if the buffer is larger, e.g. allows larger atomic writes ? I can understand that making the buffer smaller will cause trouble... but is there any (theoretical) case where an enlarged amount of data written into the pipe causes trouble ? And what about |read()|/|getmsg()| on a pipe - is there any (theoretical) scenario where buffer larger than the current default (5120 bytes) may cause trouble (existing applications will continue reading up to 5120 bytes) ? > You should feel happy that Solaris is using 5120 rather than 512 like > FreeBSD. Does FreeBSD really use 512 _bytes_ ? ---- Bye, Roland -- __ . . __ (o.\ \/ /.o) roland.ma...@nrubsig.org \__\/\/__/ MPEG specialist, C&&JAVA&&Sun&&Unix programmer /O /==\ O\ TEL +49 641 3992797 (;O/ \/ \O;) _______________________________________________ perf-discuss mailing list perf-discuss@opensolaris.org
