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Subject: Re: high CPU usage in FreeBSD for a PCIe card driver
To: Steevan Rodrigues <steevanxperia@gmail.com>
Cc: freebsd-hackers@freebsd.org
References: <CAKsGTHR9AzX2v++DbNCdt7RwxEfw8jKwndXzH9oxQEHvPszo+w@mail.gmail.com>
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 <CAKsGTHRdArYrT33KR6Kx4CqwsTR5MRaC+TQfV7yTuQej4_eOXQ@mail.gmail.com>
From: Andrew Gallatin <gallatin@cs.duke.edu>
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Date: Thu, 28 Jun 2018 12:47:05 -0400
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On 06/28/18 12:44, Steevan Rodrigues wrote:
 > Thank you so much for the suggestions .  I will use these commands.
 > Yes, I am already working on to identify lock contentions.
 >
 > Re-built FreeBSD kernel by enabling lock profiling and  now I am able to
 > see some issues with contention.
 >
 > Thanks
 > Steevan


You need-not rebuild freebsd.  lockstat is based on dtrace..

The lock profiling you're referring to is a different mechanism.

Drew