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To: Wu Fengguang <fengguang.wu@intel.com>
Cc: Andrew Morton <akpm@linux-foundation.org>, Jan Kara <jack@suse.cz>,
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Subject: Re: [PATCH 16/35] writeback: increase min pause time on concurrent dirtiers
In-Reply-To: Your message of "Tue, 14 Dec 2010 14:51:33 +0800."
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On Tue, 14 Dec 2010 14:51:33 +0800, Wu Fengguang said:

> > > +	/* (N * 10ms) on 2^N concurrent tasks */
> > > +	t = (hi - lo) * (10 * HZ) / 1024;
> > 
> > Either I need more caffeine, or the comment doesn't match the code
> > if HZ != 1000?
> 
> The "ms" in the comment may be confusing, but the pause time (t) is
> measured in jiffies :)  Hope the below patch helps.

No, I meant that 10 * HZ evaluates to different numbers depending what
the CONFIG_HZ parameter is set to - 100, 250, 1000, or some other
custom value.  Does this code behave correctly on a CONFIG_HZ=100 kernel?


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