Skip site navigation (1)Skip section navigation (2)
Date:      Tue, 5 Feb 2002 12:28:49 -0800 (PST)
From:      John Polstra <jdp@polstra.com>
To:        hackers@freebsd.org
Cc:        phk@critter.freebsd.dk
Subject:   Re: A question about timecounters 
Message-ID:  <200202052028.g15KSna04510@vashon.polstra.com>
In-Reply-To: <92661.1012938731@critter.freebsd.dk>
References:  <92661.1012938731@critter.freebsd.dk>

next in thread | previous in thread | raw e-mail | index | archive | help
In article <92661.1012938731@critter.freebsd.dk>,
Poul-Henning Kamp  <phk@critter.freebsd.dk> wrote:
> In message <200202051944.g15JiFw04286@vashon.polstra.com>, John Polstra writes:
> Could you try this combination:
> 
> 	NTIMECOUNTER = HZ  (or even 5 * HZ)
> 	tco_method = 0
> 	no splhigh protection for microuptime() ?

After 25 minutes testing that with NTIMECOUNTER=50000, I haven't
gotten any microuptime messages.  So it appears that my problem was
just that the current timecounter wrapped all the way around the ring
while microuptime was interrupted, due to the high HZ value and the
heavy interrupt load.  I'm sorry I didn't try this sooner, when you
suggested it.

After lunch I'll try NTIMECOUNTER=HZ (10000 in my case).  That sounds
like a nice default value to me.

It would be interesting to see whether this same fix also works in
-current.  I'm not sure yet if I can test that here or not.  I haven't
tried building my netgraph module under -current yet.

John
-- 
  John Polstra
  John D. Polstra & Co., Inc.                        Seattle, Washington USA
  "Disappointment is a good sign of basic intelligence."  -- Chögyam Trungpa


To Unsubscribe: send mail to majordomo@FreeBSD.org
with "unsubscribe freebsd-hackers" in the body of the message




Want to link to this message? Use this URL: <https://mail-archive.FreeBSD.org/cgi/mid.cgi?200202052028.g15KSna04510>