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Message-ID: <1383929632.2345.14.camel@ted>
From: Richard Purdie <richard.purdie@linuxfoundation.org>
To: "Hart, Darren" <darren.hart@intel.com>
Date: Fri, 08 Nov 2013 16:53:52 +0000
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Cc: openembedded-core <openembedded-core@lists.openembedded.org>
Subject: Re: [PATCH] kernel: Use hardlinks during do_install for speed
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On Fri, 2013-11-08 at 16:48 +0000, Hart, Darren wrote:
> On Fri, 2013-11-08 at 15:17 +0000, Richard Purdie wrote:
> > Whilst the comment says we can't do this, its incorrect, install operates
> > on WORKDIR and its hard for different parts of WORKDIR to be on different
> 
> Is it hard? Or is it not possible / not supported?

Not really possible unless you try very hard. Its not supported. We
don't even support WORKDIR and sysroot on different disks really.

> My understanding was it was possible and therefor we couldn't hardlink.
> I'm thrilled at the prospect of being wrong there though!

I'm happy enough to decide we don't support it (and we never have).

> > filesystems. Hardlinking instead of copying is therefore a nice performance
> > gain.
> > 
> > Also, completely skip the Documentation directory (adding a dummy Makefile
> > to keep make happy) and tweak the other cp commands to link since if we
> > don't we'd get "this is the same file" type errors from cp for some kernel
> > versions.
> > 
> > For do_install on linux-yocto, this takes it from 227s -> 84s.
> 
> This, and the others, are fantastic improvements, thanks RP!

I'm rather happy to find something we can easily fix :)

Cheers,

Richard