From nobody Wed Oct 18 17:58:36 2023 X-Original-To: freebsd-virtualization@mlmmj.nyi.freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2610:1c1:1:606c::19:1]) by mlmmj.nyi.freebsd.org (Postfix) with ESMTP id 4S9drR04fhz4xKKq for ; Wed, 18 Oct 2023 17:58:47 +0000 (UTC) (envelope-from sean@rogue-research.com) Received: from mail.rogue-research.com (mail.rogue-research.com [207.115.102.151]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (Client CN "*.rogue-research.com", Issuer "R3" (verified OK)) by mx1.freebsd.org (Postfix) with ESMTPS id 4S9drP53TKz4WLD for ; Wed, 18 Oct 2023 17:58:45 +0000 (UTC) (envelope-from sean@rogue-research.com) Authentication-Results: mx1.freebsd.org; dkim=none; spf=pass (mx1.freebsd.org: domain of sean@rogue-research.com designates 207.115.102.151 as permitted sender) smtp.mailfrom=sean@rogue-research.com; dmarc=pass (policy=none) header.from=rogue-research.com Received: from localhost (localhost [127.0.0.1]) by mail.rogue-research.com (Postfix) with ESMTP id 1DEAFF0CD59E; Wed, 18 Oct 2023 13:58:38 -0400 (EDT) X-Virus-Scanned: amavisd-new at rogue-research.com Received: from mail.rogue-research.com ([127.0.0.1]) by localhost (kingu.rogue-research.com [127.0.0.1]) (amavisd-new, port 10024) with ESMTP id T17Roiek8c4e; Wed, 18 Oct 2023 13:58:37 -0400 (EDT) Received: from [10.29.19.119] (hobgoblin.rogue-research.com [10.29.19.119]) by mail.rogue-research.com (Postfix) with ESMTPSA id 2D120F0CD58F; Wed, 18 Oct 2023 13:58:37 -0400 (EDT) From: Sean McBride To: Paul Vixie Cc: FreeBSD virtualization Subject: Re: bhyve guests: what clock source to use? Date: Wed, 18 Oct 2023 13:58:36 -0400 X-Mailer: MailMate (1.14r5937) Message-ID: <43DFA069-9A56-4266-95C5-8F536069E1C8@rogue-research.com> In-Reply-To: <349797f7-e323-04ec-f643-521c27667041@redbarn.org> References: <415C25C7-27B1-4706-BD4B-D484E4B6787B@rogue-research.com> <349797f7-e323-04ec-f643-521c27667041@redbarn.org> List-Id: Discussion List-Archive: https://lists.freebsd.org/archives/freebsd-virtualization List-Help: List-Post: List-Subscribe: List-Unsubscribe: Sender: owner-freebsd-virtualization@freebsd.org X-BeenThere: freebsd-virtualization@freebsd.org MIME-Version: 1.0 Content-Type: text/plain Content-Transfer-Encoding: quoted-printable X-Spamd-Bar: -- X-Spamd-Result: default: False [-2.29 / 15.00]; NEURAL_HAM_LONG(-1.00)[-1.000]; NEURAL_HAM_MEDIUM(-1.00)[-1.000]; SUBJECT_ENDS_QUESTION(1.00)[]; NEURAL_HAM_SHORT(-0.99)[-0.992]; R_MISSING_CHARSET(0.50)[]; DMARC_POLICY_ALLOW(-0.50)[rogue-research.com,none]; R_SPF_ALLOW(-0.20)[+mx]; MIME_GOOD(-0.10)[text/plain]; MLMMJ_DEST(0.00)[freebsd-virtualization@freebsd.org]; RCVD_TLS_LAST(0.00)[]; R_DKIM_NA(0.00)[]; FROM_EQ_ENVFROM(0.00)[]; ASN(0.00)[asn:11478, ipnet:207.115.96.0/20, country:CA]; RCPT_COUNT_TWO(0.00)[2]; TO_DN_ALL(0.00)[]; TO_MATCH_ENVRCPT_SOME(0.00)[]; FREEFALL_USER(0.00)[sean]; RCVD_VIA_SMTP_AUTH(0.00)[]; MIME_TRACE(0.00)[0:+]; FROM_HAS_DN(0.00)[]; RCVD_COUNT_THREE(0.00)[3]; ARC_NA(0.00)[]; MID_RHS_MATCH_FROM(0.00)[] X-Rspamd-Queue-Id: 4S9drP53TKz4WLD Thanks for your reply Paul. I guess what I'm ignorant of is: are the time sources available for the g= uest OS to choose from the same as the host's? i.e. are they basically p= assed through? Or are they emulated or altered by bhyve? Cheers, Sean On 14 Oct 2023, at 22:23, Paul Vixie wrote: > in the old days i used to have to hard wire it. now it picks the same v= alue i used to hard code. ntpd encountered chaos with other values. > > kern.timecounter.hardware: TSC-low > > i don't know if this has become an urban legend since i last fought it.= > > re: > > Sean McBride wrote on 2023-10-11 11:28: >> Hi all, >> >> As part of debugging a problem I'm having, I'd like to understand: >> >> What clock source should bhyve guests use? tsc? hpet? acpi_pm? What = are pros/cons of the choices? Does it depend on the guest OS? (for me Fr= eeBSD and Ubuntu) Should it match the host? >> >> Thanks, >> >> Sean >> > > > -- = > P Vixie