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From: "Richardson, Bruce" <bruce.richardson@intel.com>
To: Thomas Monjalon <thomas.monjalon@6wind.com>, Dmitry Vyal
 <dmitryvyal@gmail.com>
Thread-Topic: [dpdk-dev] Sporadic errors while initializing NICs in example
 applications, dpdk-1.5.0r1
Thread-Index: AQHO637zf5Sm98fTc0e2aLigBY+K5Jo6ec4A
Date: Thu, 28 Nov 2013 11:01:41 +0000
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References: <528F4E41.2000405@gmail.com>
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Cc: "dev@dpdk.org" <dev@dpdk.org>
Subject: Re: [dpdk-dev] Sporadic errors while initializing NICs in
	example	applications, dpdk-1.5.0r1
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>=20
> It's probably due to a frequency scaling.
> The timer based is initialized when DPDK initialize and the CPU can chang=
e
> its frequency, breaking next timers.
>=20
> The fix is to control the CPU frequency.
> Please try this, without your patch:
> 	for g in /sys/devices/system/cpu/*/cpufreq/scaling_governor; do
> echo performance >$g; done The right fix for applications (examples and
> testpmd included) could be to call rte_power_init(). Patches are welcomed=
.
>=20
[BR] Frequency changes should not affect timers for modern Intel CPUs. Plea=
se see the " Intel(r) 64 and IA-32 Architectures Software Developer's Manua=
l" Volume 3 (http://www.intel.com/content/dam/www/public/us/en/documents/ma=
nuals/64-ia-32-architectures-software-developer-system-programming-manual-3=
25384.pdf) , Section 17.13 for more details on this.=20