Advantages of 64-bit vs 32-bit on old hardware

[raymond.meyer%rambler.ru@localhost]

Do most people run NetBSD sparc64 on their UltraSparc hardware, or are there 
people like me, who prefer NetBSD sparc (32-bit sun4u kernel + 32-bit 
userland)?

I use Ultra 10 as my main desktop system. It can't take more than 1GB or RAM, 
so I don't see much point in having 64-bit operating system. Are there any 
particular advantages of a 64-bit kernel on such old hardware?

I actually think that 64-bit binaries run slower on this platform. Ultra 10 
has slow main memory, 50ns compared to modern DDR RAM, so the more 
instructions that can fit into faster cache memory, the faster they will 
execute. In fact smaller executables run faster, I build everything (kernel, 
userland, pkgsrc programs, etc) with 'gcc -Os -mcpu=ultrasparc -mvis'

Also, a lot of software in pkgsrc is not 64-bit clean. I used to run Solaris 
with 32-bit userland, compat_netbsd32 on sparc64 has problems. But now that 
NetBSD sparc port builds sunffb driver for X11 and '-mcpu=ultrasparc' 
compilation errors have been fixed, running NetBSD sparc port on UltraSparc 
hardware seems like a better alternative than sparc64.

I think this info should be made more explicit on 
http://www.netbsd.org/ports/sparc64/