Re: [PATCH] x86/boot: Support uncompressed kernel

2017-03-28 Thread Andy Lutomirski
On Tue, Mar 28, 2017 at 3:38 PM, H. Peter Anvin wrote: > On 03/28/17 05:01, Chao Peng wrote: >>> >>> I guess the next step would be to use CONFIG_XIP_KERNEL on x86, >>> which requires an uncompressed kernel but has the additional advantage >>> of sharing the read-only sections of

Re: [PATCH] x86/boot: Support uncompressed kernel

2017-03-28 Thread Andy Lutomirski
On Tue, Mar 28, 2017 at 3:38 PM, H. Peter Anvin wrote: > On 03/28/17 05:01, Chao Peng wrote: >>> >>> I guess the next step would be to use CONFIG_XIP_KERNEL on x86, >>> which requires an uncompressed kernel but has the additional advantage >>> of sharing the read-only sections of the kernel image

Re: [PATCH] x86/boot: Support uncompressed kernel

2017-03-28 Thread H. Peter Anvin
On 03/28/17 05:01, Chao Peng wrote: >> >> I guess the next step would be to use CONFIG_XIP_KERNEL on x86, >> which requires an uncompressed kernel but has the additional advantage >> of sharing the read-only sections of the kernel image across virtual >> machines, resulting in better RAM and cache

Re: [PATCH] x86/boot: Support uncompressed kernel

2017-03-28 Thread H. Peter Anvin
On 03/28/17 05:01, Chao Peng wrote: >> >> I guess the next step would be to use CONFIG_XIP_KERNEL on x86, >> which requires an uncompressed kernel but has the additional advantage >> of sharing the read-only sections of the kernel image across virtual >> machines, resulting in better RAM and cache

Re: [PATCH] x86/boot: Support uncompressed kernel

2017-03-28 Thread Chao Peng
On Mon, 2017-03-27 at 15:25 +0200, Arnd Bergmann wrote: > On Mon, Mar 27, 2017 at 1:47 PM, Michal Marek wrote: > > > > Dne 27.3.2017 v 09:58 Sebastian Andrzej Siewior napsal(a): > > > > > > On 2017-03-24 13:35:40 [+0800], Chao Peng wrote: > > > > > > > > > > > > > > > > > >

Re: [PATCH] x86/boot: Support uncompressed kernel

2017-03-28 Thread Chao Peng
On Mon, 2017-03-27 at 15:25 +0200, Arnd Bergmann wrote: > On Mon, Mar 27, 2017 at 1:47 PM, Michal Marek wrote: > > > > Dne 27.3.2017 v 09:58 Sebastian Andrzej Siewior napsal(a): > > > > > > On 2017-03-24 13:35:40 [+0800], Chao Peng wrote: > > > > > > > > > > > > > > > > > > > > > > > > > >

Re: [PATCH] x86/boot: Support uncompressed kernel

2017-03-27 Thread Arnd Bergmann
On Mon, Mar 27, 2017 at 1:47 PM, Michal Marek wrote: > Dne 27.3.2017 v 09:58 Sebastian Andrzej Siewior napsal(a): >> On 2017-03-24 13:35:40 [+0800], Chao Peng wrote: >>> >> kernel kernel sizetime in decompress_kernel >> compressed (gzip)3.3M

Re: [PATCH] x86/boot: Support uncompressed kernel

2017-03-27 Thread Arnd Bergmann
On Mon, Mar 27, 2017 at 1:47 PM, Michal Marek wrote: > Dne 27.3.2017 v 09:58 Sebastian Andrzej Siewior napsal(a): >> On 2017-03-24 13:35:40 [+0800], Chao Peng wrote: >>> >> kernel kernel sizetime in decompress_kernel >> compressed (gzip)3.3M 53ms

Re: [PATCH] x86/boot: Support uncompressed kernel

2017-03-27 Thread Michal Marek
Dne 27.3.2017 v 09:58 Sebastian Andrzej Siewior napsal(a): > On 2017-03-24 13:35:40 [+0800], Chao Peng wrote: >> > kernel kernel sizetime in decompress_kernel > compressed (gzip)3.3M 53ms > uncompressed 14M3ms >>

Re: [PATCH] x86/boot: Support uncompressed kernel

2017-03-27 Thread Michal Marek
Dne 27.3.2017 v 09:58 Sebastian Andrzej Siewior napsal(a): > On 2017-03-24 13:35:40 [+0800], Chao Peng wrote: >> > kernel kernel sizetime in decompress_kernel > compressed (gzip)3.3M 53ms > uncompressed 14M3ms >>

Re: [PATCH] x86/boot: Support uncompressed kernel

2017-03-27 Thread Chao Peng
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 sizetime in > > > > > decompress_kernel > > > > > compressed (gzip)3.3M   53ms >

Re: [PATCH] x86/boot: Support uncompressed kernel

2017-03-27 Thread Chao Peng
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 sizetime in > > > > > decompress_kernel > > > > > compressed (gzip)3.3M   53ms >

Re: [PATCH] x86/boot: Support uncompressed kernel

2017-03-27 Thread Sebastian Andrzej Siewior
On 2017-03-24 13:35:40 [+0800], Chao Peng wrote: > > > > > kernel   kernel sizetime in decompress_kernel > > > > compressed (gzip)3.3M   53ms > > > > uncompressed 14M3ms > > > > Exactly, LZ4 is the fastest. It takes 16ms to complete the

Re: [PATCH] x86/boot: Support uncompressed kernel

2017-03-27 Thread Sebastian Andrzej Siewior
On 2017-03-24 13:35:40 [+0800], Chao Peng wrote: > > > > > kernel   kernel sizetime in decompress_kernel > > > > compressed (gzip)3.3M   53ms > > > > uncompressed 14M3ms > > > > Exactly, LZ4 is the fastest. It takes 16ms to complete the

Re: [PATCH] x86/boot: Support uncompressed kernel

2017-03-24 Thread Michal Marek
On 2017-03-23 13:51, Chao Peng wrote: > Compressed kernel has its own drawback: uncompressing takes time. Even > though the time is short enough to ignore for most cases but for cases that > time is critical this is still a big number. In our on-going optimization > for kernel boot time, the

Re: [PATCH] x86/boot: Support uncompressed kernel

2017-03-24 Thread Michal Marek
On 2017-03-23 13:51, Chao Peng wrote: > Compressed kernel has its own drawback: uncompressing takes time. Even > though the time is short enough to ignore for most cases but for cases that > time is critical this is still a big number. In our on-going optimization > for kernel boot time, the

Re: [PATCH] x86/boot: Support uncompressed kernel

2017-03-23 Thread Chao Peng
> > > The patch adds a 'CONFIG_KERNEL_RAW' configure choice so the built > > > binary > > > can have no uncompressing at all. The experiment shows: > > > > > > kernel   kernel sizetime in decompress_kernel > > > compressed (gzip)3.3M   53ms > > >

Re: [PATCH] x86/boot: Support uncompressed kernel

2017-03-23 Thread Chao Peng
> > > The patch adds a 'CONFIG_KERNEL_RAW' configure choice so the built > > > binary > > > can have no uncompressing at all. The experiment shows: > > > > > > kernel   kernel sizetime in decompress_kernel > > > compressed (gzip)3.3M   53ms > > >

Re: [PATCH] x86/boot: Support uncompressed kernel

2017-03-23 Thread Sergey Senozhatsky
On (03/23/17 08:07), Yinghai Lu wrote: > On Thu, Mar 23, 2017 at 5:51 AM, Chao Peng > wrote: > > Compressed kernel has its own drawback: uncompressing takes time. Even > > though the time is short enough to ignore for most cases but for cases that > > time is

Re: [PATCH] x86/boot: Support uncompressed kernel

2017-03-23 Thread Sergey Senozhatsky
On (03/23/17 08:07), Yinghai Lu wrote: > On Thu, Mar 23, 2017 at 5:51 AM, Chao Peng > wrote: > > Compressed kernel has its own drawback: uncompressing takes time. Even > > though the time is short enough to ignore for most cases but for cases that > > time is critical this is still a big number.

Re: [PATCH] x86/boot: Support uncompressed kernel

2017-03-23 Thread Yinghai Lu
On Thu, Mar 23, 2017 at 5:51 AM, Chao Peng wrote: > Compressed kernel has its own drawback: uncompressing takes time. Even > though the time is short enough to ignore for most cases but for cases that > time is critical this is still a big number. In our on-going

Re: [PATCH] x86/boot: Support uncompressed kernel

2017-03-23 Thread Yinghai Lu
On Thu, Mar 23, 2017 at 5:51 AM, Chao Peng wrote: > Compressed kernel has its own drawback: uncompressing takes time. Even > though the time is short enough to ignore for most cases but for cases that > time is critical this is still a big number. In our on-going optimization > for kernel boot