clock(3) in error

[Michael J. Baars]

On Tue, 2021-07-20 at 18:22 +0200, Luis Javier Merino wrote:
> > > On 19/07/2021 08:34, Michael J. Baars via Libc-alpha wrote:
> > > > Hi,
> > > > 
> > > > I've been using the clock() function for years now. Until recently I thought the timing mechanism worked perfectly, then I tried to let the actual time
> > run
> > > > next
> > > > to it. As it appears, the clock() function isn't working as perfectly as I thought.
> > > > 
> > > > As a consequence, my internet connection from T-Mobile, which I don't have anymore, so I can't show you the actual speed with the clock() corrected,
> > wasn't
> > > > running at 100mbit/s but a lot slower. The same holds for all other T-Mobile customers in Holland. I hope that someone is willing to have a look at the
> > > > glibc
> > > > clock() function and repair it. A lot of people would benefit from that.
> 
> Note that clock() returns the CPU time used by the process, not the wall-clock time. 

I prefer this XS4ALL 100mbit fiber optic cable anyway :)
-------------- next part --------------
# clock_0 (process)

inet socket             half duplex - packet size 131072 -    0.9027 gbit/s
inet socket             half duplex - packet size  65536 -    0.7757 gbit/s
inet socket             half duplex - packet size  32768 -    0.6915 gbit/s
inet socket             half duplex - packet size  16384 -    0.3642 gbit/s
inet socket             half duplex - packet size   8192 -    0.2197 gbit/s
inet socket             half duplex - packet size   4096 -    0.1178 gbit/s
inet socket             half duplex - packet size   2048 -    0.0778 gbit/s
inet socket             half duplex - packet size   1024 -    0.0390 gbit/s
inet socket             half duplex - packet size    512 -    0.0258 gbit/s

inet socket             full duplex - packet size 131072 -    1.7187 gbit/s
inet socket             full duplex - packet size  65536 -    1.4714 gbit/s
inet socket             full duplex - packet size  32768 -    1.3250 gbit/s
inet socket             full duplex - packet size  16384 -    0.7913 gbit/s
inet socket             full duplex - packet size   8192 -    0.3718 gbit/s
inet socket             full duplex - packet size   4096 -    0.1737 gbit/s
inet socket             full duplex - packet size   2048 -    0.1262 gbit/s
inet socket             full duplex - packet size   1024 -    0.0410 gbit/s
inet socket             full duplex - packet size    512 -    0.0264 gbit/s

# clock_1 (system)

inet socket             half duplex - packet size 131072 -  384.4419 mbit/s
inet socket             half duplex - packet size  65536 -  394.4794 mbit/s
inet socket             half duplex - packet size  32768 -  338.1600 mbit/s
inet socket             half duplex - packet size  16384 -  234.4915 mbit/s
inet socket             half duplex - packet size   8192 -  162.5055 mbit/s
inet socket             half duplex - packet size   4096 -  108.5021 mbit/s
inet socket             half duplex - packet size   2048 -   68.1359 mbit/s
inet socket             half duplex - packet size   1024 -   43.7110 mbit/s
inet socket             half duplex - packet size    512 -   27.5559 mbit/s

inet socket             full duplex - packet size 131072 -  573.5007 mbit/s
inet socket             full duplex - packet size  65536 -  480.9169 mbit/s
inet socket             full duplex - packet size  32768 -  480.8279 mbit/s
inet socket             full duplex - packet size  16384 -  365.5978 mbit/s
inet socket             full duplex - packet size   8192 -  255.9557 mbit/s
inet socket             full duplex - packet size   4096 -  142.3687 mbit/s
inet socket             full duplex - packet size   2048 -  103.3635 mbit/s
inet socket             full duplex - packet size   1024 -   44.5703 mbit/s
inet socket             full duplex - packet size    512 -   28.4246 mbit/s