RE: booting NetBSD/vax on real hardware

[Mark Pizzolato - Info Comm <Mark%infocomm.com@localhost>]

On Tuesday, May 27, 2014 at 4:28 AM, Martin Husemann wrote:
> On Tue, May 27, 2014 at 12:33:12PM +0200, Martin Husemann wrote:
> > Spot on - not the decompress code, but the crc32() function in libsa.
> > The optimized one in libkern uses large tables, but that makes it fast
> > on VAX. The tiny one in libsa computes it all on the fly - and seems
> > to be dog slow on VAX.
> >
> > I'm testing a change to switch back to the libkern one for VAX.
> 
> Unfortunately that didn't do the trick. But still we should have an asm 
> version
> of crc32 using the crc instruction. Anyone?

Hmmm...  DEC changed away from using the CRC instruction as VMS versions 
progressed.  This drastically improved VMS Backup performance where CRC was the 
bottleneck.

Additionally, CRC as an instruction is emulated on all but the older hardware.  
I don't think this is happening early enough to have instruction emulation 
running....

- Mark