ping 127.0.0.1 takes too much
Scott Wood
scottwood at freescale.com
Sat Jan 19 09:48:58 EST 2008
DI BACCO ANTONIO - technolabs wrote:
> I have two different boards: one with MPC875 running at 66 MHz cpu/66
> MHz bus, one with MPC880 running at 132 MHz cpu /66MHz bus, I load the
> same kernel and root file system on both the boards that have only
> different u-boot(s).
>
> If I do a ping 127.0.0.1 on the MPC875 I get a round trip of 0.300 ms,
> while on the other one I get 0.900 ms, I expected the opposite.
>
> Could be an issue with memory configuration? In the formula to calculate
> the PTx on the MPC885RM manual I used 66 MHz as "system clock" for the
> first board and 132 MHz for the second board. Probably this is a mistake
> because "system clock" should be the bus clock but how this can so
> adversely affect the ping round trip?
Are you sure the timebase clock is what the kernel thinks it is? Does
the time-of-day clock progress at the correct rate?
-Scott
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