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From: Andi Kleen <andi@firstfloor.org>
To: "Américo Wang" <xiyou.wangcong@gmail.com>
Cc: Andi Kleen <andi@firstfloor.org>, linux-kernel@vger.kernel.org
Subject: Re: 2.6.33 pagemap endless read loop
Date: Tue, 12 Jan 2010 17:28:24 +0100	[thread overview]
Message-ID: <20100112162823.GC7363@basil.fritz.box> (raw)
In-Reply-To: <20100112153208.GF3925@hack>

> Hmm, could you please try:
> 
>      time cat /proc/self/pagemap >/dev/null
> 

I stopped it after a minute of CPU time...

Obviously reading 47bits of zeroes take a long time.

-Andi
-- 
ak@linux.intel.com -- Speaking for myself only.

  reply	other threads:[~2010-01-12 16:28 UTC|newest]

Thread overview: 11+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2010-01-10  2:09 2.6.33 pagemap endless read loop Andi Kleen
2010-01-10  6:33 ` Américo Wang
2010-01-10 12:37   ` Andi Kleen
2010-01-12  5:59     ` Mike Galbraith
2010-01-12 15:32     ` Américo Wang
2010-01-12 16:28       ` Andi Kleen [this message]
2010-01-13  2:08         ` Américo Wang
     [not found] ` <20100113141648.42eff724.akpm@linux-foundation.org>
     [not found]   ` <1263421562.29868.5000.camel@calx>
     [not found]     ` <20100113143055.7bea30c5.akpm@linux-foundation.org>
     [not found]       ` <1263423916.29868.5009.camel@calx>
     [not found]         ` <20100113151502.fa425247.akpm@linux-foundation.org>
     [not found]           ` <20100114055319.GA17671@localhost>
     [not found]             ` <20100113221013.b1beecb4.akpm@linux-foundation.org>
2010-01-14  8:06               ` Wu Fengguang
2010-01-14  8:30                 ` Andi Kleen
2010-01-14  8:52                   ` [PATCH] pagemap: early return on unmapped areas Wu Fengguang
2010-01-14 17:02                     ` Matt Mackall

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