Re: incorrect ping(8) interval with powerd(8)

In message: <20050616070445.GD2239_at_obiwan.tataz.chchile.org>
            Jeremie Le Hen <jeremie_at_le-hen.org> writes:
: Hi Warner,
: 
: > : %%%
: > :     jarjarbinks:root# sysctl hw.acpi.acline
: > :     hw.acpi.acline: 1
: > :     jarjarbinks:root# sysctl dev.cpu.0.freq
: > :     dev.cpu.0.freq: 1735
: > :     jarjarbinks:root# time ping -qc 2 192.168.1.1
: > :     PING 192.168.1.1 (192.168.1.1): 56 data bytes
: > :     
: > :     --- 192.168.1.1 ping statistics ---
: > :     2 packets transmitted, 2 packets received, 0% packet loss
: > :     round-trip min/avg/max/stddev = 0.266/0.269/0.271/0.002 ms
: > :     
: > :     real    0m1.003s
: > :     user    0m0.001s
: > :     sys     0m0.001s
: > : 
: > :     jarjarbinks:root# sysctl hw.acpi.acline
: > :     hw.acpi.acline: 0
: > :     jarjarbinks:root# sysctl dev.cpu.0.freq
: > :     dev.cpu.0.freq: 216
: > :     jarjarbinks:root# time ping -qc 2 192.168.1.1
: > :     PING 192.168.1.1 (192.168.1.1): 56 data bytes
: > :     
: > :     --- 192.168.1.1 ping statistics ---
: > :     2 packets transmitted, 2 packets received, 0% packet loss
: > :     round-trip min/avg/max/stddev = 0.637/0.814/0.991/0.177 ms
: > :     
: > :     real    0m2.252s
: > :     user    0m0.004s
: > :     sys     0m0.021s
: > : %%%
: > : 
: > : I check ping(8) source code and it appears it uses select(8) to wait
: > : the desired amount of time.  I don't think this is the intended
: > : behaviour.  Where does this bug (feature?) come from ?
: > 
: > Those numbers look about right for a 200MHz CPU.
: 
: May you delve into this a little bit more please ?  The ping(8) manual
: page states that the -i flags makes ping(8) to wait a given couple of
: seconds.  If I use the flags "-i 1", I expect ECHO Requests to be sent
: with one second between each, whatever the AC line status is.
: (Note that I didn't explicitely specified "-i 1" in the above example,
: but this doesn't change the behaviour.)

Well, the rount trip times went way up (3x longer).  That's normal for
a 200MHz CPU...  My 333MHz EISA machine can't do much better than
that.

But the 2.252s run time is a little longish.  Do you see this
consistantly?  If you ran it a second time would you get identical
results.  I've seen ARP take a while...  What else do you have running
on the system?  Maybe a daemon that takes almost no time at 1.7GHz
takes a lot longer at 200Mhz and that's starving the ping process...
Or some driver has gone insane...

Warner