Re: www.softpanorama.org: sparc_vs_x86 fun

Jan Engelhardt
2006-05-04T11:36:51Z

>>Solaris is heterogeneous OS that (unlike Linux) can perform well on two
>>architectures: UltraSparc and Intel.

There are a lot of places where there seem to be artificial delays.

>>5.1. UltraSparc is an expensive but pretty cool CPU :-)
>>...
>>* Energy efficiency: it consumes less energy then either Intel or Opteron
>> and much less then PoewerPC CPUs.

Approx 82-85 W for an Opteron 244; according to Wikipedia, a T1 is 79 W.
UltraSPARC IV at 109 W (competes with P4 :p)

>>* Fault tolerance. Sun servers can do amazing things with fauly components.
>> almost any of them can be switched off. Even low level Sun server like V240
>> can survive bam memory chips, onle falty CPU and one burned power supply.
>> In some somce it is an cheap cluster.

I once pulled one power cable from a 2-PSU E250 machine. It powered off.
That can't be fault tolerant.
Plus you can't replace components (in an E250) without turning the power
off. That's because opening the case disconnects the power circle.

>>* Cleaner architecture. Being big Endean CPU with RISC instruction set
>> provides some complier level advantages in comparison with convoluted
>> instruction set of X86 line.

Except that the instruction length is a bit shortcoming for 64-bit integer
math. Under x64, you can do

movq $biglongconstant, %rax

while on SPARC, it takes 6 instructions (of course, being RISC makes it
execute differently than x64)

sethi %g1, $some_upper_bits
or %g1, $next_bitgroup
(shift-left)
or %g1, $next_bitgroup
(shift-left)
or %g1, $last_bitgroup

BTW, T1 is cool, but that the 1U version only has space for 1 disk is
pretty limiting :/

Jan Engelhardt
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