From nobody Mon Sep 13 17:36:40 2021 X-Original-To: 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 E522C17CCAC4 for ; Mon, 13 Sep 2021 17:36:40 +0000 (UTC) (envelope-from bugzilla-noreply@freebsd.org) Received: from mxrelay.nyi.freebsd.org (mxrelay.nyi.freebsd.org [IPv6:2610:1c1:1:606c::19:3]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (4096 bits) server-digest SHA256 client-signature RSA-PSS (4096 bits) client-digest SHA256) (Client CN "mxrelay.nyi.freebsd.org", Issuer "R3" (verified OK)) by mx1.freebsd.org (Postfix) with ESMTPS id 4H7YZ02xyCz3k1l for ; Mon, 13 Sep 2021 17:36:40 +0000 (UTC) (envelope-from bugzilla-noreply@freebsd.org) Received: from kenobi.freebsd.org (kenobi.freebsd.org [IPv6:2610:1c1:1:606c::50:1d]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (4096 bits) server-digest SHA256) (Client did not present a certificate) by mxrelay.nyi.freebsd.org (Postfix) with ESMTPS id 41023364D for ; Mon, 13 Sep 2021 17:36:40 +0000 (UTC) (envelope-from bugzilla-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 18DHaeY4076729 for ; Mon, 13 Sep 2021 17:36:40 GMT (envelope-from bugzilla-noreply@freebsd.org) Received: (from www@localhost) by kenobi.freebsd.org (8.15.2/8.15.2/Submit) id 18DHaemm076728 for virtualization@FreeBSD.org; Mon, 13 Sep 2021 17:36:40 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: virtualization@FreeBSD.org Subject: [Bug 254513] virtio_random: random_harvestq spinning on a CPU with Q35 virtio random device Date: Mon, 13 Sep 2021 17:36:40 +0000 X-Bugzilla-Reason: AssignedTo CC X-Bugzilla-Type: changed X-Bugzilla-Watch-Reason: None X-Bugzilla-Product: Base System X-Bugzilla-Component: misc X-Bugzilla-Version: 13.0-STABLE X-Bugzilla-Keywords: performance, regression X-Bugzilla-Severity: Affects Many People X-Bugzilla-Who: cem@freebsd.org X-Bugzilla-Status: New X-Bugzilla-Resolution: X-Bugzilla-Priority: --- X-Bugzilla-Assigned-To: virtualization@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: 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 X-ThisMailContainsUnwantedMimeParts: N https://bugs.freebsd.org/bugzilla/show_bug.cgi?id=3D254513 --- Comment #23 from Conrad Meyer --- We read a lot from random sources we expect to be =E2=80=9Cfast=E2=80=9D, l= ike virtio-rng. https://github.com/freebsd/freebsd-src/blob/main/sys/dev/random/random_harv= estq.c#L231 10Hz x 4B x HARVESTSIZE x (max) RANDOM_KEYSIZE_WORDS x 32 pools http://fxr.watson.org/fxr/source/dev/random/random_harvestq.h#L32 http://fxr.watson.org/fxr/source/dev/random/hash.h#L37 Up to about 20 kB/s. --=20 You are receiving this mail because: You are the assignee for the bug. You are on the CC list for the bug.=