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Message-ID: <1490606744.3661.7.camel@linux.intel.com>
Subject: Re: [PATCH] x86/boot: Support uncompressed kernel
From: Chao Peng <chao.p.peng@linux.intel.com>
To: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Cc: Sergey Senozhatsky <sergey.senozhatsky@gmail.com>,
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Date: Mon, 27 Mar 2017 17:25:44 +0800
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On Mon, 2017-03-27 at 09:58 +0200, Sebastian Andrzej Siewior wrote:
> On 2017-03-24 13:35:40 [+0800], Chao Peng wrote:
> > 
> > 
> > > 
> > > > 
> > > > > 
> > > > >     kernel               kernel size    time in
> > > > > decompress_kernel
> > > > >     compressed (gzip)    3.3M           53ms
> > > > >     uncompressed         14M            3ms
> > > > 
> > Exactly, LZ4 is the fastest. It takes 16ms to complete the
> > decompression. Still sounds a little longer when compared to
> > uncompressed kernel.
> 
> Are we seriously talking here about one-time improvement of 13ms
> boot time?

The usage model for us is to lunch kernel in virtual machine and there
will be thousands of instances lunched and shutdowned/re-lunched
frequently, so every single million-second helps. And 13ms means 20%
improvement to our existing optimization (the other part besides
decompression is optimized to ~40ms).

Chao
> 
> > 
> > Chao
> 
> Sebastian