DO i need SMP support in Kernel
 

Hi i am using Slackware 11.0 with default kernel 2.4.33.3. i am planning to compile kernel 2.6.20.6(I have already done that for my current pc Intel 2.8 Ghz) but now i want to compile for my pc which has intel 3.0 Ghz Hyper Threading Capability. I am in a dilemma whether to opt for SMP option or not because i don't know what is the difference between Hyper threading CPU and Dual core Cpu. I guess for Dual core we must enable Smp support as it boosts performance(correct me if i am wrong) but i am not sure about my CPU i.e INTEL 3.0 Ghz HT(hyper threading)

Kindly guide me(Is this topic supposed to be in hardware forum ? if so i am really sorry,kindly don't flame)

Yes, you would want SMP on, and I think there's also an option specifically for hyperthreading.

Yes there is specific hyperthreading for the scheduler, instead of multi-core.

http://www.intel.com/technology/hyperthread/index.htm

a link on what hyperthreading is. Dual or Quad core is fairly self explanatory.

Simultaneous Multi-Threading (SMT, aka HyperThreading) allows a single execution core to run multiple threads simultaneously. This occurs because not all parts of the core are working at once under many conditions. SMP has many cores. The kernel MUST be SMP-aware to use either technology. It should also have the SMT scheduler for hyperthreading, so the schedulre can adapt to the parallel workload better.

Hi there
 

Step by step

1) Enable HyperThreading in your BIOS

2) Compile your kernel with SMP support and with support fot SMT (HyperThreading)

#
# Processor type and features
#
CONFIG_SMP=y

...

CONFIG_NR_CPUS=8
CONFIG_SCHED_SMT=y

# Where NR_CPUS is the maximum number of CPUs you want
# to be supported, and SCHED_SMT is for HyperThreading

3) At this point you should have support for HyperThreading (I suggest using the config files from the new Slackware kernels).

From my console:

david@evenstar:~$ cat /proc/cpuinfo
processor : 0
vendor_id : GenuineIntel
...
bogomips : 5589.61
...

processor : 1
vendor_id : GenuineIntel
...
bogomips : 5585.26


From my system logs:

...
Apr 23 07:17:54 evenstar kernel: Total of 2 processors activated (11174.85 BogoMIPS).
...
Apr 23 07:17:54 evenstar kernel: checking TSC synchronization across 2 CPUs: passed.
Apr 23 07:17:54 evenstar kernel: Brought up 2 CPUs
...



May the Force be with you!

thanks
 

thank you for reply i got it


cheeers