Date: Thu, 27 Jun 2019 18:57:12 +0400 From: Antranig Vartanian <antranigv@freebsd.am> To: FreeBSD Questions <freebsd-questions@freebsd.org> Subject: Re: hw.ncpu changes after recent updates Message-ID: <CAN4C8SHKqK__wmo=keeXVRZxQkeSWY6wte=x9_Kfns1f4Tezhg@mail.gmail.com> In-Reply-To: <20190627143034.GA9574@mon.zyxst.net> References: <20190627143034.GA9574@mon.zyxst.net>
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Hi J. Hyper-Threading[1] is a technology which allows running two threads on one core, however since Intel had multiple security issues, many people have turned it off, not sure you did that manually or has been changed during an update. so yes, if you had ncpu=8 before, now it should be 4 :) 1: https://en.m.wikipedia.org/wiki/Hyper-threading On Thu, Jun 27, 2019, 6:31 PM tech-lists <tech-lists@zyxst.net> wrote: > Hi, > > Possibly a silly question, but is it expected that hw.ncpu would change > after the recent intel cpu related updates? > > hw.ncpu used to be 8, is now 4. CPU is i7-4770K > machdep.hyperthreading_allowed=0 > > thanks, > -- > J. >
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