Hello, katmai karbonellenc <katmai.mo...@gmail.com> schrieb am Fr., 19. Apr. 2019, 02:29:
> > You almost certainly dont have 8 cores - you probably have a 4 core CPU > > with hyperthreading. > > By default Qubes disables hyperthreading for security reasons. > I have looked at the output of the commands: model name : Intel(R) Core(TM) i7-7700K CPU (...) cpu cores : 4 and you are referring to the right CPU spec sheet The specifications of this CPU: > > https://www.intel.co.uk/content/www/uk/en/products/processors/core/i7-processors/i7-7700k.html There you can find the information: # of Cores = 4 # of Threads = 8 (...) Intel Hyper-Threading Technology = Yes As such you only have 4 real cores and Qubes is correct telling you this information. Why deactivate Hyperthreading? QSB #43: L1 Terminal Fault speculative side channel (XSA-273) https://www.qubes-os.org/news/2018/09/02/qsb-43/ (...) Part of the mitigation is to disable hyper-threading. This halves the number of CPU cores that the system sees compared to having hyper-threading enabled, thus reducing system performance. Since Qubes OS 4.0 uses both PVH and HVM qubes, it is _not_ safe to re-enable hyper-threading. If you have previously modified the number of virtual CPUs assigned to any qube (the "vcpus" property), it may be necessary to adjust this value in order to account for reduced system performance. (...) If you are interested in Hyperthreading performance tests, you might be interesting looking into this article: Intel Hyper Threading Performance With A Core i7 On Ubuntu 18.04 LTS https://www.phoronix.com/scan.php?page=article&item=intel-ht-2018&num=1 Regards - O/799 t <https://groups.google.com/d/optout>. -- You received this message because you are subscribed to the Google Groups "qubes-users" group. To unsubscribe from this group and stop receiving emails from it, send an email to qubes-users+unsubscr...@googlegroups.com. To post to this group, send email to qubes-users@googlegroups.com. To view this discussion on the web visit https://groups.google.com/d/msgid/qubes-users/CAJ3yz2s5isb_TdTTgxPPvyjzeD-OY67e89ufFtthbMms8brmYw%40mail.gmail.com. For more options, visit https://groups.google.com/d/optout.
