From: "Chris Friesen" <cfriesen@nortel.com>
To: Brian McGrew <brian@visionpro.com>
Cc: linux-kernel@vger.kernel.org
Subject: Re: mmap vs. real memory
Date: Thu, 10 Sep 2009 17:16:02 -0600 [thread overview]
Message-ID: <4AA988B2.4060102@nortel.com> (raw)
In-Reply-To: <C6CECDE3.13A4A%brian@visionpro.com>
On 09/10/2009 04:38 PM, Brian McGrew wrote:
> Now that we are needing more and more shared memory, we're seeing random
> performance issues. With 16MB, 64MB and 256MB (in recent past) all was
> good. But now, trying to allocate 1GB of shared memory, we see it taking
> anywhere from .6 to 9 SEONDS to access the file. No good!
>
> What I'm wondering and needed to do is map a chunk of mymoery (1GB today,
> maybe 2GB later on) so that all my apps can access it. Short of creating a
> ramdisk and moving the mmap'ed file to ramdisk, what is the best way to do
> this???
Maybe make a ramfs partition, mount it somewhere, and create your file
there? This is more efficient and simpler than creating a ramdisk.
Alternately, have you considered using hugetlbfs and mapping the shared
memory with large pages?
Chris
next prev parent reply other threads:[~2009-09-10 23:16 UTC|newest]
Thread overview: 3+ messages / expand[flat|nested] mbox.gz Atom feed top
2009-09-10 22:38 mmap vs. real memory Brian McGrew
2009-09-10 23:16 ` Chris Friesen [this message]
2009-09-11 9:25 ` Luciano Rocha
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