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Date:      Thu, 29 Jul 1999 23:03:14 +0900
From:      "Daniel C. Sobral" <dcs@newsguy.com>
To:        Matthew Dillon <dillon@apollo.backplane.com>
Cc:        hackers@FreeBSD.ORG
Subject:   MADV_SEQUENTIAL and GNU Grep
Message-ID:  <37A05F22.5AA2D27D@newsguy.com>
References:  <199907290439.XAA69977@celery.dragondata.com> <199907290445.VAA66252@apollo.backplane.com>

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Matthew Dillon wrote:
> 
>     MADV_SEQUENTIAL *WILL* work.   It changes the page fault
>     read-behind/read-ahead.  Normally the VM system reads behind a bit as well
>     as reads ahead.  If you set MADV_SEQUENTIAL it shifts to just doing
>     read-ahead, and it does more of it.

So it works, then? GNU grep has this #ifdef'ed out, with a comment
about it impacting negatively on performance on BSD 4.1. I recall
some rants on this subject a couple of years ago... If it is
working, I'd like to change that 0 to 1 in our tree.

--
Daniel C. Sobral			(8-DCS)
dcs@newsguy.com
dcs@freebsd.org

	"Is it true that you're a millionaire's son who never worked a day
in your life?"
	"Yeah, I guess so."
	"Lemme tell you, son, you ain't missed a thing."



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