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My sony vaio has a processor model: Intel® Core™ i7-3517U It appears to me as being 4 cores but it does not show the threads. What is wrong? How could I fix it? How can I access that information? I just want to check that my 4 x 2 virtual threads are really there working at the fullest! ;)


  • OS type: ubuntu 13.10 64-bit
  • Processor: Intel® Core™ i7-3517U CPU @ 1.90GHz × 4(cores)

Obs.: The computer came with windows 8, but I do not like windows, then I swap to ubuntu! But it was working with 8 threads before, I checked myself, but in ubuntu I can't find this information.

Any help I will appreciate! Cheers!

Follow my file /proc/cpuinfo information

processor   : 0
vendor_id   : GenuineIntel
cpu family  : 6
model       : 58
model name  : Intel(R) Core(TM) i7-3517U CPU @ 1.90GHz
stepping    : 9
microcode   : 0x12
cpu MHz     : 800.000
cache size  : 4096 KB
physical id : 0
siblings    : 4
core id     : 0
**cpu cores : 2**
apicid      : 0
initial apicid  : 0
fpu     : yes
fpu_exception   : yes
cpuid level : 13
wp      : yes
flags       : fpu vme de pse tsc msr pae mce cx8 apic sep mtrr pge mca cmov pat pse36 clflush dts acpi mmx fxsr sse sse2 ss ht tm pbe syscall nx rdtscp lm constant_tsc arch_perfmon pebs bts rep_good nopl xtopology nonstop_tsc aperfmperf eagerfpu pni pclmulqdq dtes64 monitor ds_cpl vmx est tm2 ssse3 cx16 xtpr pdcm pcid sse4_1 sse4_2 x2apic popcnt tsc_deadline_timer aes xsave avx f16c rdrand lahf_lm ida arat epb xsaveopt pln pts dtherm tpr_shadow vnmi flexpriority ept vpid fsgsbase smep erms
bogomips    : 4788.76
clflush size    : 64
cache_alignment : 64
address sizes   : 36 bits physical, 48 bits virtual
power management:

I added only information about processor 0, there are 3 more processors but not so different from this one.

share|improve this question
Please add the contents of the file /proc/cpuinfo to your question and double check that hyperthreading is enabled in your bios. Also note that hyperthreading adds little to nothing once you have more than one core anyhow. – psusi Dec 29 '13 at 2:55
@psusi I added the cpuinfo file, it does not show any thread in there. But it shows cpu cores : 2 what is it? – B4NZ41 Dec 29 '13 at 16:11
The 4 cores are the threads. You have two real cores that are each hyperthreaded, for a total of 4. – psusi Dec 29 '13 at 19:03
Thanks. I got it now. – B4NZ41 Dec 30 '13 at 14:19

The easy way to get information about the number of CPU threads in your system (and lots of other useful information) is to install Sysinfo from the Ubuntu Software Center. Sysinfo is a graphical tool that is able to display some hardware and software information about the computer it is run on. In the CPU category, Sysinfo displays vendor identification, model name, frequency, number of cores, number of threads, level2 cache, bogomips, model numbers and flags.

You can view real time information about what each one of your CPU threads is doing in the System Monitor application in the Resources tab under the CPU History heading. If your computer is idle, your CPU usage should normally be very low.

share|improve this answer
Hi @Karel I installed the Sysinfo, but the software do not display the Thread information, besides it shows all information I already know. Weird situation! – B4NZ41 Dec 29 '13 at 16:04
Click on CPU. On the first line is Vendor. After that there will be the vendor name, something like Genuineintel if your computer has an Intel processor. On the second line there is CPUs, and after that something like 4 if your computer has a dual core CPU with 4 threads. If Sysinfo does not show something similar to this on your computer (the output may be different depending on your hardware), then Sysinfo is not functioning the way it should, and it could be reported as a bug. – karel Dec 29 '13 at 20:45

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