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From:   Florian Weimer <fw@deneb.enyo.de>
To:     Da Shi Cao <dscao999@gmail.com>
Cc:     linux-kernel@vger.kernel.org, linux-x86_64@vger.kernel.org
Subject: Re: [BUG]Uncalibrated TSC is not accurate enough as a time keeper
References: <CAG3POBnGPabdLQ2wvJc9HTKeHszf+RytV6t+hPyh0k=hjGd+8g@mail.gmail.com>
Date:   Thu, 27 Dec 2018 18:35:13 +0100
In-Reply-To: <CAG3POBnGPabdLQ2wvJc9HTKeHszf+RytV6t+hPyh0k=hjGd+8g@mail.gmail.com>
        (Da Shi Cao's message of "Sun, 23 Dec 2018 14:56:01 +0800")
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* Da Shi Cao:

> The cpu_khz and tsc_khz are now read directly by the cpuid
> instruction, and they are deemed to be very accurate. But this is not
> the case in our situation. The OS time lags behind about 8 seconds per
> hour. The CPU information is as follows:

Is virtualization involved?  Do you use a vendor kernel?

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