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Date: Thu, 12 Feb 2009 13:15:08 -0800
From: Bakul Shah <bakul@bitblocks.com>
Message-Id: <20090212211508.7CF795B21@mail.bitblocks.com>
Subject: Re: pahole - Finding holes in kernel structs 
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> >>>> So I ran the tool pahole over a 7.1 FreeBSD Kernel, and found that
> >>>> many of the struct had holes, and some of which could be rearranged to
> >>>> fill the gap.

...

> Certainly plugging holes can also be beneficial but just cautioning that 
> changes of this sort need to be checked if made to critical data 
> structures.  OTOH there aren't that many that matter in practice.

But why do it?  Are the benefits worth churning any ABIs?