Re: Kernel Options

On 11/19/19 6:57 PM, T wrote:
> Hello,
> I've been trying out some kernel options and wanted to document a few 
> things on here, and to perhaps see if other similar peer machines are 
> also having the same results. Here's a list of the options with brief 
> notes:
>
> options DIAGNOSTIC
> #Causes the kernel to panic, after the bootloader stage. This was 
> enabled for the secondary kernel, did not have it enabled in the 
> bootloader kernel.
>
> options KGDB
> #This will lead to compile errors if enabled. I was able to track down 
> the errors to some changes that were made that did not take OEA type 
> machines into consideration. I was able to move some IFDEF tags to 
> fix, although there was one error I could not figure out, but was able 
> to bypass in order to get the kernel to compile. I'll follow up with 
> more information/patch when I return to this issue.
>
> options BUFQ_READPRIO
> #When this was enabled, it fixed a problem where the UI would appear 
> to become stuck. Large amounts of IO to external storage devices 
> through PCI bus adapters (i.e. SATA, USB) would trigger this problem. 
> I have updated this ticket with more specific information: 
> http://gnats.netbsd.org/33291
>
> options BUFQ_PRIOCSCAN
> #This causes the kernel to panic. I tried to enable it because many of 
> the other ports have it enabled by default and was curious if it would 
> also fix the problem mentioned directly above. I was told that this is 
> the better buffer queue strategy, which would explain why the above 
> buffer queue strategy is rarely enabled in the default kernel 
> configuration files of other ports. I have yet to try FCFS, but 
> probably will in the near future. Some background on " Buffer Queue 
> Strategies": 
> https://mail-index.netbsd.org/netbsd-users/2015/12/02/msg017432.html
>
> I will submit these to gnats if I can get some sort of confirmation 
> that these are reproducible on a different machine. If more 
> information is needed, let me know.

I just noticed in the current source that BUFQ_PRIOCSCAN has been 
enabled by default in port-prep (others too), has anyone had issues with 
current on their machine?
http://cvsweb.netbsd.org/bsdweb.cgi/src/sys/arch/prep/conf/GENERIC?only_with_tag=MAIN

As noted above, this option caused a kernel panic when it was enabled.