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Date: Wed, 30 Mar 2016 19:50:16 +0200
From: David Sterba <dsterba@suse.cz>
To: Liu Bo <bo.li.liu@oracle.com>
Cc: linux-btrfs@vger.kernel.org
Subject: Re: [PATCH] btrfs: fallback to vmalloc in btrfs_compare_tree
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On Wed, Mar 30, 2016 at 10:10:45AM -0700, Liu Bo wrote:
> On Wed, Mar 30, 2016 at 04:05:43PM +0200, David Sterba wrote:
> > The allocation of node could fail if the memory is too fragmented for a
> > given node size, practically observed with 64k.
> 
> It's not a critical path.  Why not use vmalloc directly?

We should try to avoid vmalloc if possible.