From owner-freebsd-virtualization@freebsd.org Tue Aug 21 17:06:31 2018 Return-Path: Delivered-To: freebsd-virtualization@mailman.ysv.freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2610:1c1:1:606c::19:1]) by mailman.ysv.freebsd.org (Postfix) with ESMTP id 2DD711079401 for ; Tue, 21 Aug 2018 17:06:31 +0000 (UTC) (envelope-from simplerezo@gmail.com) Received: from mail-lf1-x133.google.com (mail-lf1-x133.google.com [IPv6:2a00:1450:4864:20::133]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (Client CN "smtp.gmail.com", Issuer "Google Internet Authority G3" (verified OK)) by mx1.freebsd.org (Postfix) with ESMTPS id 8481B8CD5D for ; Tue, 21 Aug 2018 17:06:30 +0000 (UTC) (envelope-from simplerezo@gmail.com) Received: by mail-lf1-x133.google.com with SMTP id q13-v6so6651399lfc.2 for ; Tue, 21 Aug 2018 10:06:30 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=mime-version:sender:from:date:message-id:subject:to; bh=ub0/QRnhcrk/hWClqAypIugwyQiGnfCzQEn9FuhoABY=; b=ml6v5yibBeIExBr02AgXPQcuWFCGrPnAlQ+aU0cyUzy/G3ylXHVUs27+zMhtPd6aap wIZQTNWzo6lMSk/LIu+xq/1O8B/hE1uTTHDYMNUg3ZQ2GcFHtmojf5FFN1nJYQ/pSLvh /0ZDhFwCFPFGQC4QemlG5uSPGoqa2O6YCtzVVVdglDLaiRcQqlq6FzgZpahic9JgjaHA 4PsS7jefnWlDBBAg1yN8q555QAEvsYVarlzbD9MZ7gZlAWlxFRvR8sugDhHoVJcXbv// EOVQnBf9UWbku1yvE3G3CPWBD5LGPP7zLn0d6cHow6t7PuQ7t/6BYHqXoTuiRaMPDAnH 1ULQ== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:mime-version:sender:from:date:message-id:subject :to; bh=ub0/QRnhcrk/hWClqAypIugwyQiGnfCzQEn9FuhoABY=; b=mUYgbMOxX83UyFnXEyR8b2HJwRCnaa7Ie5H/kJtpWjDjkrHj+/sltCvYHcXE5BmZbQ GRY2N9KfGzmfJAN1AKb4n87c/wBF/HzWT9eEpIvj9dNNtMztIl6UuXxqdkMxovoxsrm9 sImtlRYJhjTUzgtXUYI4FcuNanvVn8yvBzrGzGFOqd1/3Kc3cI3+SIIBXG9p8sPkKYZc l9PvxD5oVWgTiBw9PFB5e+swkk1PPYrnw0gy+ZNaIERYXTTJEVsACqZyBxAuLZlQ/AVU XvLE3SGhRfV+QZhuChRjpWv8zoL1VRZcsqprX5hs9IPhrG22wNDQVjgnLUWwB7bm0Of2 otPQ== X-Gm-Message-State: AOUpUlEdFJWKYGrSGo4eoH6oBtDtIwUfn9oEtdDtWFBOvaz81gZyf0VR gRD1Zs3r9GCgves8V+Hmz65MEQw9zF3sQwEUqNa2Pejp X-Google-Smtp-Source: AA+uWPzi9NdQqm01fm8JCEdFQxcfSyNdrsLi7XAmBwaX4SnJj9E0sdxsN2u3efwnTtPYBgCCyMa0pgXDkiDzIa0FibA= X-Received: by 2002:a19:124d:: with SMTP id h74-v6mr14193855lfi.107.1534871189128; Tue, 21 Aug 2018 10:06:29 -0700 (PDT) MIME-Version: 1.0 Sender: clement.moulin@gmail.com X-Google-Sender-Delegation: clement.moulin@gmail.com From: Support SimpleRezo Date: Tue, 21 Aug 2018 19:06:18 +0200 X-Google-Sender-Auth: czjzhnzjjltwT6N-rVV5wk2Xke8 Message-ID: Subject: [HyperV-2016] urandom performance issue... To: freebsd-virtualization@freebsd.org Content-Type: text/plain; charset="UTF-8" X-Content-Filtered-By: Mailman/MimeDel 2.1.27 X-BeenThere: freebsd-virtualization@freebsd.org X-Mailman-Version: 2.1.27 Precedence: list List-Id: "Discussion of various virtualization techniques FreeBSD supports." List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Tue, 21 Aug 2018 17:06:31 -0000 Hi list! I was figuring a performance issue of a FreeBSD on HyperV, after: - moving it from an Hyper-V 2012 host to a Hyper-V 2016 - updating to FreeBSD 11.2 (custom kernel, but same issue with GENERIC) After loosing some times because i was thinking about hardware issue (disk controller was my first thought...) and testing with "dd if=/dev/urandom"... I discovered this... I ran the following test... and quite surprised by the speed result! $ dd if=/dev/urandom of=/dev/null bs=10M count=3 3+0 records in 3+0 records out 31457280 bytes transferred in 27.960431 secs (1125064 bytes/sec) The test was also sometimes "freezing" the Hyper-V host! Looking into "dmesg" i have found this: random: registering fast source Intel Secure Key RNG random: fast provider: "Intel Secure Key RNG" So I rebuilt my KERNEL without "rdrand_rng" (didn't find another way to disable it...)... and performances went back to normal! I think this issue should documented on https://wiki.freebsd.org/HyperV ! Regards -- Clement SimpleRezo