anyone measured context-switch cost on Linux/ia32?

[Larry McVoy]

: > Has anyone measured the cost (in cycles or time) of the
: > context-switch path in Linux/ia32?
: 
: here, on a celeron and a slightly hacked UP kernel, a context switch
: (time between one process stops executing, is preempted, and another
: starts running) is ~4800 cycles (10.7us) at best. stock kernels are
: probably not much different in this area.

lmbench, 2 process no working set case:

	500Mhz Celeron, 2.2.14 Mandrake 7.0, 1.8usecs
	400Mhz PPC (iMac), 2.2.14 Yellow dog 1.0(?), 1.4usecs
	500Mhz Alpha, 2.2.13 Red hat 6.1, 2.3usecs

There's something wrong with either your benchmark or your system.  10usecs
is more like Solaris :-)

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