I wrote:
>I also want to measure the speed of SysV semaphores for the graph. It
>occurs to me that since they never imply data transfer, and since they
>don't involve the file system in any way, they may be faster than
>named pipes to drive the out-of-process graph or subgraphs.
the problem with semaphores is that Unix/POSIX semantics don't allow
integration of a process sleeping on an file descriptor and a
semaphore (one of the few areas where Windows definitely improves upon
Unix). this would mean adding yet another thread that just sleeps on
the semaphore used to drive the "process" callback. Not terrible, but
not particularly great either. The code would be a little cleaner, but
we'd have an extra thread for every client. Uhm.
--p
