Re: Fwd: [GIT PULL] timer changes for v3.10

2013-05-09 Thread Ingo Molnar
* Pavel Machek pa...@ucw.cz wrote: [I still wonder how adjtime is going to work in TSC(runtime)+RTC(s2disk) case; surely TSC has different drift than RTC, and so adjtime will have fun trying to estimate the drift... but that's not new problem and not affected by that patch.] NTP, once it

Re: Fwd: [GIT PULL] timer changes for v3.10

2013-05-08 Thread Ingo Molnar
* Pavel Machek pa...@ucw.cz wrote: Sorry. You seem to not like the merged change, but I guess I'm not quite sure what exactly your objection is here. I'm not exactly sure what my objections are. TSC was not designed for long-term precise timekeeping. [...] The TSC is just a 64-bit

Re: Fwd: [GIT PULL] timer changes for v3.10

2013-05-08 Thread Pavel Machek
Hi! Sorry. You seem to not like the merged change, but I guess I'm not quite sure what exactly your objection is here. I'm not exactly sure what my objections are. TSC was not designed for long-term precise timekeeping. [...] The TSC is just a 64-bit counter that can be read

Re: Fwd: [GIT PULL] timer changes for v3.10

2013-05-08 Thread Feng Tang
Hi Pavel, On Wed, May 08, 2013 at 12:55:42PM +0200, Pavel Machek wrote: Hi! Sorry. You seem to not like the merged change, but I guess I'm not quite sure what exactly your objection is here. I'm not exactly sure what my objections are. TSC was not designed for long-term

Re: Fwd: [GIT PULL] timer changes for v3.10

2013-05-08 Thread Thomas Gleixner
Pavel, On Wed, 8 May 2013, Pavel Machek wrote: Sorry. You seem to not like the merged change, but I guess I'm not quite sure what exactly your objection is here. I'm not exactly sure what my objections are. TSC was not designed for long-term precise timekeeping. [...]

Re: Fwd: [GIT PULL] timer changes for v3.10

2013-05-08 Thread Pavel Machek
Hi! [...] but some people suspend their machines for longer than that. Plus I wonder how it will interfere with /etc/adjtime. If it's precise then why should it interfere? The history of the TSC being problematic can be ignored the moment CPU makers fix it completely -

Re: Fwd: [GIT PULL] timer changes for v3.10

2013-05-07 Thread Ingo Molnar
* Feng Tang feng.t...@intel.com wrote: is even worse than that. Machine can stay is s2ram for weeks (for a lot more if it is desktop and you do s2ram for powersaving). Also temperature of CPU varies a lot between active and s2ram states. Is TSC good enough? Yes, I think it is

Re: Fwd: [GIT PULL] timer changes for v3.10

2013-05-07 Thread Feng Tang
Hi Ingo, On Tue, May 07, 2013 at 08:53:48AM +0200, Ingo Molnar wrote: * Feng Tang feng.t...@intel.com wrote: is even worse than that. Machine can stay is s2ram for weeks (for a lot more if it is desktop and you do s2ram for powersaving). Also temperature of CPU varies a lot

Re: Fwd: [GIT PULL] timer changes for v3.10

2013-05-07 Thread John Stultz
On 05/06/2013 11:53 PM, Ingo Molnar wrote: * Feng Tang feng.t...@intel.com wrote: is even worse than that. Machine can stay is s2ram for weeks (for a lot more if it is desktop and you do s2ram for powersaving). Also temperature of CPU varies a lot between active and s2ram states. Is TSC good

Re: Fwd: [GIT PULL] timer changes for v3.10

2013-05-07 Thread Ingo Molnar
* John Stultz john.stu...@linaro.org wrote: On 05/06/2013 11:53 PM, Ingo Molnar wrote: * Feng Tang feng.t...@intel.com wrote: is even worse than that. Machine can stay is s2ram for weeks (for a lot more if it is desktop and you do s2ram for powersaving). Also temperature of CPU varies a

Re: Fwd: [GIT PULL] timer changes for v3.10

2013-05-07 Thread John Stultz
On 05/07/2013 02:31 PM, Pavel Machek wrote: On Tue 2013-05-07 09:01:36, John Stultz wrote: On 05/06/2013 11:53 PM, Ingo Molnar wrote: * Feng Tang feng.t...@intel.com wrote: is even worse than that. Machine can stay is s2ram for weeks (for a lot more if it is desktop and you do s2ram for

Re: Fwd: [GIT PULL] timer changes for v3.10

2013-05-07 Thread Pavel Machek
Hi! is even worse than that. Machine can stay is s2ram for weeks (for a lot more if it is desktop and you do s2ram for powersaving). Also temperature of CPU varies a lot between active and s2ram states. Is TSC good enough? Yes, I think it is relatively precise. Per our test, system time

Re: Fwd: [GIT PULL] timer changes for v3.10

2013-05-06 Thread Feng Tang
Hi Pavel, On Tue, May 07, 2013 at 09:10:42AM +0800, Feng Tang wrote: -- Forwarded message -- From: Pavel Machek pa...@ucw.cz Date: 2013/5/7 Subject: Re: [GIT PULL] timer changes for v3.10 To: Ingo Molnar mi...@kernel.org Cc: Linus Torvalds torva...@linux-foundation.org,