Re: polling interval

On Tue, 15 Oct 2024 11:25:39 +0100
void <void@f-m.fm> wrote:

> On Tue, Oct 15, 2024 at 05:41:35PM +0900, Tomoaki AOKI wrote:
> 
> >FYI, I'm configuring kern.hz=4096 in /boot/loader.conf. Lost where I've
> >seen, but recommended by somewhere.
> 
> all offloading at source, host and destination turned off, default kern.hz in vm
> ================================================================================
> - - - - - - - - - - - - - - - - - - - - - - - - -
> [ ID] Interval           Transfer     Bitrate         Retr
> [  5]   0.00-60.06  sec  4.46 GBytes   637 Mbits/sec  1326             sender
> [  5]   0.00-60.07  sec  4.45 GBytes   637 Mbits/sec                  receiver
> 
> same as above, but with kern.hz=8
> - - - - - - - - - - - - - - - - - - - - - - - - -
> [ ID] Interval           Transfer     Bitrate         Retr
> [  5]   0.00-60.02  sec  4.45 GBytes   637 Mbits/sec  1148             sender
> [  5]   0.00-60.02  sec  4.45 GBytes   637 Mbits/sec                  receiver
> 
> as above, kern.hz=4096
> - - - - - - - - - - - - - - - - - - - - - - - - -
> [ ID] Interval           Transfer     Bitrate         Retr
> [  5]   0.00-60.07  sec  3.09 GBytes   441 Mbits/sec  1013             sender
> [  5]   0.00-60.07  sec  3.09 GBytes   441 Mbits/sec                  receiver
> 
> With all offloading turned off, not seeing incorrect checksums at the
> destination now.
> -- 

Maybe kern.hz=4096 would be too large (short time per tick) for your
VMs, as VMs basically need more time than bare metal for emulated
(virtualized) syscalls or some instructions by mature.

And possibly (as I don't use offloading on VirtualBox that is the only
VM I tried) interactions between host (emulated hardware) and guests
about offloading has some issues.

-- 
Tomoaki AOKI    <junchoon@dec.sakura.ne.jp>