3 Nov
2005
3 Nov
'05
5:16 p.m.
>>>> "J" == J C Wren <J.C.>
writes:
J> Do you remember the CDC song? "I/O, I/O, it's off to disk we go!
J> Put CIO in RA+1, I/O, I/O..."
Eek.
It's amazing to me that still to this day lots of people do not know
that circular buffers are the way to do inter-processor communication
without interlocking. For example, RTLinux did (perhaps still does)
have to disable interrupts for its IPC, because it uses queue
structures that aren't interrupt-safe, rather than CIO style buffers
that are. In systems like that, the penalty for not knowing the right
technology is pretty steep.
paul