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[66.158.149.132]) by smtp.gmail.com with ESMTPSA id u12sm16549840qkk.129.2021.04.06.14.42.16 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Tue, 06 Apr 2021 14:42:16 -0700 (PDT) From: Maxim Cournoyer References: Date: Tue, 06 Apr 2021 17:42:15 -0400 In-Reply-To: (Leo Famulari's message of "Thu, 18 Mar 2021 02:25:26 -0400") Message-ID: <87zgybnl8o.fsf@gmail.com> User-Agent: Gnus/5.13 (Gnus v5.13) Emacs/27.2 (gnu/linux) MIME-Version: 1.0 Content-Type: multipart/mixed; boundary="=-=-=" X-BeenThere: debbugs-submit@debbugs.gnu.org X-Mailman-Version: 2.1.18 Precedence: list X-BeenThere: bug-guix@gnu.org List-Id: Bug reports for GNU Guix List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: 47225@debbugs.gnu.org Errors-To: bug-guix-bounces+larch=yhetil.org@gnu.org Sender: "bug-Guix" X-Migadu-Flow: FLOW_IN ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=yhetil.org; s=key1; t=1617745398; h=from:from:sender:sender:reply-to:subject:subject:date:date: message-id:message-id:to:to:cc:cc:mime-version:mime-version: content-type:content-type:resent-cc:resent-from:resent-sender: resent-message-id:in-reply-to:in-reply-to:references:references: list-id:list-help:list-unsubscribe:list-subscribe:list-post: dkim-signature; bh=tE4xPrA54jjTKRpt47YLjzf1wj9vb/HgGwxDut0a+Xs=; b=JhnM/zSBZJMKQ01hou5i8VtRRRgcIvENtiS4O5RhX8RwVRgYN/DTGZzlgUM8xxr1tF5YT6 4KSrrxi/Ld9b74UiL6WRugkhgb7L9nCg196bbi7p4jPUc0+9YV+E+96lQwXNHoR/VqL4uW PUrR3F02j1VM7wOOnLJ9x+oJ47e77UJYMfX6V480LXwIRTrBtWa4jF0BBxCUUJtl8y9QBM sMuH6jYPrVXRFU7Nf9YrEG7MqsbOS1rn6LBf5WLdwCE95FAJjqLmjPNy6C5oRMem1VklFP TfHVXDnDgF82rhIcubl5I94uq36G1AcnTjXVk22xd2Bw0NW0tfmy4E3AyudK6g== ARC-Seal: i=1; s=key1; d=yhetil.org; t=1617745398; a=rsa-sha256; cv=none; b=IznG+VD9qjxjYfQ4qL2AUWi1MgZwqZmGYUhVrDHL+YYYA5o26bNj6NCX+lWMhNhrivNJik VWoZU+IJgxtH90q3grx4z3SizPLkKCG1xbketKj2XRaVA0AslJ3aT+a8amyTECg2m7It3F I3WUxZUH/hvu1E/8PHK22oQgs7wd0v+WIdYNB7lY0LYwQoE5hkmGtykOJUb0riZTZKZiSH cWZE52HtFMmHj6Q7rhzyws8z1N4FEaoZqz/i+Ax5FiCrk5nnxLgljidgYxF2Ffe0xgs4CS E9E/AtUtSGDqIcSC4tdWKfFNpj0a94/Oxpd8vLSIHzejLFihKKNl+zm/RnYH1Q== ARC-Authentication-Results: i=1; aspmx1.migadu.com; dkim=fail ("headers rsa verify failed") header.d=gmail.com header.s=20161025 header.b="h/lgkK4E"; spf=pass (aspmx1.migadu.com: domain of bug-guix-bounces@gnu.org designates 209.51.188.17 as permitted sender) smtp.mailfrom=bug-guix-bounces@gnu.org X-Migadu-Spam-Score: -1.34 Authentication-Results: aspmx1.migadu.com; dkim=fail ("headers rsa verify failed") header.d=gmail.com header.s=20161025 header.b="h/lgkK4E"; dmarc=fail reason="SPF not aligned (relaxed)" header.from=gmail.com (policy=none); spf=pass (aspmx1.migadu.com: domain of bug-guix-bounces@gnu.org designates 209.51.188.17 as permitted sender) smtp.mailfrom=bug-guix-bounces@gnu.org X-Migadu-Queue-Id: ED3A911772 X-Spam-Score: -1.34 X-Migadu-Scanner: scn0.migadu.com X-TUID: 5duyNnUwBoic --=-=-= Content-Type: text/plain Hi Leo, Leo Famulari writes: > While using `guix system vm`, I noticed this warning. I think it's new, > maybe from the 5.2.0 update? > > ------ > qemu-system-x86_64: warning: 9p: degraded performance: a reasonable > high msize should be chosen on client/guest side (chosen msize is <= > 8192). See https://wiki.qemu.org/Documentation/9psetup#msize for > details. > ------ > > That web page suggests that we increase the virtio packet size when > declaring the 9p file-systems, I think in %linux-vm-file-systems of (gnu > system vm). The attached patch should fix it (it does for me at least!). --=-=-= Content-Type: text/x-patch Content-Disposition: attachment; filename=0001-system-vm-Set-a-larger-value-for-the-msize-option-of.patch >From c720e68229322e5c38c0321b021e8d6430636111 Mon Sep 17 00:00:00 2001 From: Maxim Cournoyer Date: Tue, 6 Apr 2021 17:37:33 -0400 Subject: [PATCH] system: vm: Set a larger value for the msize option of the 9p file system. Fixes . * gnu/system/vm.scm (mapping->file-system): Set the msize option to a value of 100 MiB (from the default 8 KiB). Reported-by: Leo Famulari --- gnu/system/vm.scm | 10 +++++++++- 1 file changed, 9 insertions(+), 1 deletion(-) diff --git a/gnu/system/vm.scm b/gnu/system/vm.scm index 3d0935b3af..f9cf39ae42 100644 --- a/gnu/system/vm.scm +++ b/gnu/system/vm.scm @@ -581,7 +581,15 @@ the operating system." (type "9p") (flags (if writable? '() '(read-only))) (options (string-append "trans=virtio" - (if writable? "" ",cache=loose"))) + (if writable? "" ",cache=loose") + ;; By default, the msize value is 8 KiB, which + ;; according to QEMU is insufficient and would + ;; degrade performance. The msize value should + ;; roughly match the bandwidth of the system's + ;; IO (see: + ;; https://wiki.qemu.org/Documentation/9psetup#msize). + ;; Use 100 MiB as a conservative default. + ",msize=104857600")) (check? #f) (create-mount-point? #t))))) -- 2.31.1 --=-=-= Content-Type: text/plain Thank you for the report, Maxim --=-=-=--