1

I have the latest Mint installation on an Intel Atom D2550 CPU, which is a dual core processor. When Hyper Threading is enabled in BIOS lscpu reports 4 cores (0-3), which I can also see crunching away in System Monitor.

However, when I turn Hyper Threading off in BIOS lscpu reports:

CPU(s):                2
On-line CPU(s) list:   0,2

So the number of real cores is 2 (which is correct) but their numbering is 0,2 instead of the expected 0,1. The System Monitor also shows 2 cores but one being (always) inactive, like this:

enter image description here

When I list the processes by processor I get half of the processes on P0 and the rest on P2.

How can I report the correct Core/Processor numbers?

Deemoss
  • 11
  • 2
  • Number of cores is not the issue (2 vs 4 with HT). The problem is that without HT they are reported as "On-line CPU(s) list: 0,2" where it should be 0,1 (first core should be 0 and second 1). – Deemoss Oct 06 '18 at 06:21
  • Do you have documentation that shows the two half cores should be numbered sequentially? If so, it sounds like you need to report a kernel bug. – roaima Oct 06 '18 at 07:24
  • I haven't seen the documentation but all other reports I see are sequential i.e. 0,1 (2 core) or 0,1,2,3 (4 core) etc. The problem is that some software rely on this numbering for their functionality (as shown on my System Report screenshot above. – Deemoss Oct 06 '18 at 09:35
  • You should specify that in your question and also see the answers to the question posted by roaima. It seems like your questions concerns the number of cores. The way that cores are assigned and reported has nothing to do with whether or not you have hyperthreading enabled or disabled. – Nasir Riley Oct 06 '18 at 14:46
  • @NasirRiley The only reason I mentioned Hyper Threading is that when I use it the numbering is correct when I don't use it the numbering is wrong: 0,1,2,3 (4 cores) vs 0,2 (2 cores) – Deemoss Oct 06 '18 at 19:32
  • It isn't wrong. The kernel doesn't always assign numbers to cores sequentially. See the question on roaima's comment. – Nasir Riley Oct 06 '18 at 21:37

0 Answers0