gzilla-noreply@freebsd.org) Received: from kenobi.freebsd.org ([127.0.1.5]) by kenobi.freebsd.org (8.15.2/8.15.2) with ESMTP id 4569MogH011040 for ; Thu, 6 Jun 2024 09:22:50 GMT (envelope-from bugzilla-noreply@freebsd.org) Received: (from www@localhost) by kenobi.freebsd.org (8.15.2/8.15.2/Submit) id 4569MoAN011039 for bugs@FreeBSD.org; Thu, 6 Jun 2024 09:22:50 GMT (envelope-from bugzilla-noreply@freebsd.org) X-Authentication-Warning: kenobi.freebsd.org: www set sender to bugzilla-noreply@freebsd.org using -f From: bugzilla-noreply@freebsd.org To: bugs@FreeBSD.org Subject: [Bug 271826] FreeBSD is disastrously slow on a PowerMac G5, freezing at every command Date: Thu, 06 Jun 2024 09:22:50 +0000 X-Bugzilla-Reason: AssignedTo X-Bugzilla-Type: changed X-Bugzilla-Watch-Reason: None X-Bugzilla-Product: Base System X-Bugzilla-Component: misc X-Bugzilla-Version: 13.2-RELEASE X-Bugzilla-Keywords: needs-qa, performance X-Bugzilla-Severity: Affects Some People X-Bugzilla-Who: mitch_com@hotmail.com X-Bugzilla-Status: Open X-Bugzilla-Resolution: X-Bugzilla-Priority: --- X-Bugzilla-Assigned-To: bugs@FreeBSD.org X-Bugzilla-Flags: X-Bugzilla-Changed-Fields: Message-ID: In-Reply-To: References: Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: quoted-printable X-Bugzilla-URL: https://bugs.freebsd.org/bugzilla/ Auto-Submitted: auto-generated List-Id: Bug reports List-Archive: https://lists.freebsd.org/archives/freebsd-bugs List-Help: List-Post: List-Subscribe: List-Unsubscribe: Sender: owner-freebsd-bugs@FreeBSD.org MIME-Version: 1.0 https://bugs.freebsd.org/bugzilla/show_bug.cgi?id=3D271826 --- Comment #35 from Mitch --- (In reply to Justin Hibbits from comment #33) Yesterday I've tried Ben's patch and my machine was way happier, unfortunat= ely the same problem still occurs, just less often. I was able to install 14.1 and use it for a few minutes before the machine crashed while idling. Just trying to understand why we'd want to use memory barriers with the powermac_smp_timebase_sync function. Is it because PPC is using a weak memory model which would be problematic i= n an SMP context like explained below ? https://preshing.com/20120710/memory-barriers-are-like-source-control-opera= tions/ https://preshing.com/20120930/weak-vs-strong-memory-models/ You mentioned that the code is derived from mpc85xx, do we have such a mach= ine in the field which is running a modern release properly ? Also how was FreeBSD handling timebase sync before the introduction of plateform_powermac ? I'll try your suggestions and test it again. --=20 You are receiving this mail because: You are the assignee for the bug.=