[dpdk-dev] Sporadic errors while initializing NICs in example applications, dpdk-1.5.0r1

[Thomas Monjalon]

Thomas29/11/2013 13:25,  Monjalon :
> 29/11/2013 14:53, Dmitry Vyal :
> > On 11/28/2013 03:01 PM, Richardson, Bruce wrote:
> > > [BR] Frequency changes should not affect timers for modern Intel CPUs.
> > 
> > The error frequency greatly reduces if I patch
> > loop limit as I described earlier or if I call rte_power_init and
> > rte_power_freq_max as Thomas suggested.
> > 
> > But the only way to get rid of them completely is to set performance
> > governor.
> 
> Please check that your hardware do not support invariant TSC.
> It would explain why you need to fix frequency.
> 
> I attach a simple code to test CPU feature "Invariant TSC".

Note that this feature is called constant_tsc in /proc/cpuinfo:
	grep --color -m1 constant_tsc /proc/cpuinfo
It is checked by check_tsc_flags() at DPDK initialization and should print a 
warning if missing:
http://dpdk.org/browse/dpdk/commit/?id=e7c8996e13b9abb706ea0de53271346f4f86ca03

-- 
Thomas