[syslinux] "Tick-counting" vs "Tick-less" timekeeping issues on VMs emulating BIOS PCs

[H. Peter Anvin]

On 03/01/16 07:21, Patrick Masotta via Syslinux wrote:
> 
> At the moment I'm seeing timing issues on TFTP transfers (lwIP depends
> on the new interrupt based timer). I have consistently detected 
> 
> multiple Requests, double ACKs, etc. All these problems seem to be
> 
> sourced on the now unreliable timeouts.
> I have used TFTP on the same (BIOS VM) scenarios with 3.X and TFTP 
> 
> timing was always rock solid.
> 
> 
> Sorry if this was discussed before, if not I'd like to ask (Peter) if 
> there is any reason preventing us from going back to the "Tick-less" 
> approach. Thanks.
> 

There are quite a few; primarily we simply cannot make lwIP
(lpxelinux.0) work without it.  However, pxelinux.0 should not depend on
this.

	-hpa