From mboxrd@z Thu Jan  1 00:00:00 1970
From: Grant Grundler <iod00d@hp.com>
Date: Thu, 02 Jun 2005 01:34:21 +0000
Subject: Re: [RFC] vmalloc with the ability to specify a node
Message-Id: <20050602013421.GS25321@esmail.cup.hp.com>
List-Id: <linux-ia64.vger.kernel.org>
References: <Pine.LNX.4.62.0506011551240.10915@schroedinger.engr.sgi.com>
In-Reply-To: <Pine.LNX.4.62.0506011551240.10915@schroedinger.engr.sgi.com>
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To: Christoph Lameter <clameter@engr.sgi.com>
Cc: linux-mm@kvack.org, linux-ia64@vger.kernel.org

On Wed, Jun 01, 2005 at 03:52:42PM -0700, Christoph Lameter wrote:
> I was surprised to see that some drivers allocate memory structures
> using vmalloc.

It's drivers I care about. :^(

grundler@gsyprf3:/usr/src/linux-2.6$ fgrep vmalloc drivers/net/*/*c
drivers/net/e1000/e1000.mod.c:  { 0xd6ee688f, "vmalloc" },
drivers/net/e1000/e1000_main.c: txdr->buffer_info = vmalloc(size);
drivers/net/e1000/e1000_main.c: rxdr->buffer_info = vmalloc(size);
drivers/net/ixgb/ixgb.mod.c:    { 0xd6ee688f, "vmalloc" },
drivers/net/ixgb/ixgb_main.c:   txdr->buffer_info = vmalloc(size);
drivers/net/ixgb/ixgb_main.c:   rxdr->buffer_info = vmalloc(size);
grundler@gsyprf3:/usr/src/linux-2.6$ fgrep vmalloc drivers/scsi/*/*c
drivers/scsi/qla2xxx/qla2xxx.mod.c:     { 0xd6ee688f, "vmalloc" },
drivers/scsi/qla2xxx/qla_os.c:#include <linux/vmalloc.h>
drivers/scsi/qla2xxx/qla_os.c:                  ha->fw_dump_buffer = (char *)vmalloc(dump_size);

Could someone explain to me why this is a bad thing on NUMA machines?
I assume it has something to do with mem locality and how the memory
is used.

> Only tested in a limited way. Boots fine. Is this worth doing?

Any difference in performance?
Any clue why it matters?

grant