Re:Re:Re: [chrony-users] How does chrony "speed up" the system clock

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And is there any way to make subsequent "sleep"s not influenced by chrony's speeding up?

Thanks :-)

At 2017-09-03 17:10:03, "xxhdx1985126" <xxhdx1985126@xxxxxxx> wrote:

By the way, I guess the subsequent "nanosleep" will also be influenced just like "sleep", right?

At 2017-09-02 14:18:52, "Bill Unruh" <unruh@xxxxxxxxxxxxxx> wrote: >Yes it would. If the clock were slowed by 500PPM (which is a large slew rate) >a 1 second sleep would take all of .5 milli seconds longer. Now chrony can >slow the clock more than that but only under severe circumstances and never by >more than 10%. > > >You can tell chrony to jump the clock if its error is too large. (that is an >infinite slew rate), but that will not happen. In normal operation the slew >rate may change by a few parts per million-- ie, it is not something to worry >about. > > > >William G. Unruh __| Canadian Institute for|____ Tel: +1(604)822-3273 >Physics&Astronomy _|___ Advanced Research _|____ Fax: +1(604)822-5324 >UBC, Vancouver,BC _|_ Program in Cosmology |____ unruh@xxxxxxxxxxxxxx >Canada V6T 1Z1 ____|____ and Gravity ______|_ > >On Sat, 2 Sep 2017, xxhdx1985126 wrote: > >> Hi, everyone >> >> I'm a newbie to chrony. I saw these words in "chronyc manual page": "any error in the system clock >> is corrected by slightly speeding up or slowing down the system clock until the error has been >> removed, and then returning to the system clock’s normal speed". I wonder what does the "speed up >> the system clock" mean? Would it influence the execution of glibc APIs like "sleep"? I mean if >> chrony decides to speed up the system clock, would sebsequent "sleep" function calls take less time >> to return? And is there a max error bound in time for chrony? >> >> Thanks very much:-) >> >> >>   >> >> >> >>   >> >> >>


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