Ouaich, SMP is supported, and I am sure that ROSS's dual CPU modules are supported as you can see by yourself:
piou@ywing:~ > cat /proc/cpuinfo cpu : ROSS HyperSparc RT625 or RT626 fpu : ROSS HyperSparc combined IU/FPU promlib : Version 3 Revision 2 prom : 2.25 type : sun4m ncpus probed : 2 ncpus active : 2 Cpu0Bogo : 125.33 Cpu1Bogo : 125.33 MMU type : ROSS HyperSparc invall : 0 invmm : 0 invrnge : 0 invpg : 0 contexts : 4096 CPU0 : online CPU1 : online piou@ywing:~ >
The SparcStation 10 and SparcStations 20 are SMP capable computers and according to the FAQABOSS the following combinations are known to work :
And, as stated earlier, CPU modules in SparcStations 10 and can run a different clock speeds, the following ones __SHOULD__ work:
How does it performs? Well, it is fast, really fast. Some of the java
Demos can run faster on a dual HyperSparc 125Mhz 128MB ( ywing ) than on a dual
celeron BP6 433@433Mhz 192MB ( calimero ). The same applies for the Gimp. When it
comes to compiling calimero runs faster than ywing. Both computers
running 2.2.16 kernel and calimero's hard disk subsystem is full SCSI.
One important detail when you plan to have different CPU modules in your computer is to have the same kind of modules, you cannot mix SuperSparc and HyperSparc for example, but you can have an odd number of CPUs, for example 3. They are said to be able to run modules at different clock speed as written in this article form AcesHardware , but I have not witnessed it.
ywing has been upgraded to quad-CPU. You can read the
kernel's message:
cpu : ROSS HyperSparc RT625 or RT626 fpu : ROSS HyperSparc combined IU/FPU promlib : Version 3 Revision 2 prom : 2.25 type : sun4m ncpus probed : 4 ncpus active : 4 Cpu0Bogo : 125.33 Cpu1Bogo : 125.33 Cpu2Bogo : 125.33 Cpu3Bogo : 125.33 MMU type : ROSS HyperSparc invall : 0 invmm : 0 invrnge : 0 invpg : 0 contexts : 4096 CPU0 : online CPU1 : online CPU2 : online CPU3 : online
and its main memory is now 256MB:
total: used: free: shared: buffers: cached: Mem: 263028736 29114368 233914368 22958080 1695744 12779520 Swap: 133849088 0 133849088 MemTotal: 256864 kB MemFree: 228432 kB MemShared: 22420 kB Buffers: 1656 kB Cached: 12480 kB BigTotal: 0 kB BigFree: 0 kB SwapTotal: 130712 kB SwapFree: 130712 kB
So I have performed an empirical proftpd compilation test using the
make -JN. The results are:
with make real 3m27.466s user 3m15.670s sys 0m12.030s with make -j2 real 1m52.670s user 3m27.210s sys 0m15.310s with make -j3 real 1m22.560s user 3m43.910s sys 0m18.070s with make -j4 real 1m13.582s user 4m2.200s sys 0m22.830s with make -j5 real 1m13.445s user 4m4.060s sys 0m22.640s with make -j8 real 1m15.550s user 4m1.840s sys 0m22.960s with make -j 10 real 1m20.091s user 4m2.440s sys 0m22.170s
As expected the best results are with make -j5 ( one instance per CPU + one ready to enter when a cache miss occurs ); then N increasing the results are starting to worsen.
As a conclusion, those sun4m SMP systems will be very
interesting when Gimp 2.0 will be available because of multitreading
and paralelization of algorithms.
If you want to learn more about SMP and Linux you can read the
SMP-HOWTO
http://www.tldp.org/HOWTO/SMP-HOWTO.html