From owner-freebsd-scsi@freebsd.org Tue Oct 3 06:22:10 2017 Return-Path: Delivered-To: freebsd-scsi@mailman.ysv.freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:1900:2254:206a::19:1]) by mailman.ysv.freebsd.org (Postfix) with ESMTP id CAEF5E3231B; Tue, 3 Oct 2017 06:22:10 +0000 (UTC) (envelope-from ben.rubson@gmail.com) Received: from mail-wm0-x231.google.com (mail-wm0-x231.google.com [IPv6:2a00:1450:400c:c09::231]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (Client CN "smtp.gmail.com", Issuer "Google Internet Authority G2" (verified OK)) by mx1.freebsd.org (Postfix) with ESMTPS id 5BE7266661; Tue, 3 Oct 2017 06:22:10 +0000 (UTC) (envelope-from ben.rubson@gmail.com) Received: by mail-wm0-x231.google.com with SMTP id m72so9768187wmc.0; Mon, 02 Oct 2017 23:22:10 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=mime-version:subject:from:in-reply-to:date:cc :content-transfer-encoding:message-id:references:to; bh=YZkiMsy6BmmyyYQlVQZD5mwcE7j2oPo3X0avPs5Z+II=; b=Zxezx4WKo7BbmdBfWso+T2JwMrRUxz/uewl+kvbwbn/TPxh8Jz1hzzwDayUCb7QcF2 voS5oQfL6fSab9AHatgzkYnhjM2DnjEM2NeVdAxC3zCACf7uXmGDklUzUdvSYOfTutDT wVZ5K2GTWXcu654GveBgFdrE9AnJkVM4Y7jQolPA38uOc17/OIWO0ozJG1E/vkORxBTL iF9+03P0k6C4fG7ROWfPjC9Mpgcg+m5mpvajetY4yQLnjd04/mAGvlhaxv4XJ37v949A 6oqb7vOJSWCnDhDAZ/bHwwmOL2vUbZrCyTrAkwQ/dY4vOlVjianilE7ua6KJsdupj5Ls A3MA== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:mime-version:subject:from:in-reply-to:date:cc :content-transfer-encoding:message-id:references:to; bh=YZkiMsy6BmmyyYQlVQZD5mwcE7j2oPo3X0avPs5Z+II=; b=VOsy/oUfx18DAu0LEbZzRYWrH6GdykLzcHJv0J3UOpKC8j3O7o06uvCkMlC/+EY9UI cZ1JsosDMYCnkSRMkp574KLncsUcuzTz4GSruoK6rgvz8qh7louLjqC/xgthhK4WJBnA 7lcRAi9vyxXpvASNYfM9WlTJkiMjV9kE93L1SScGGpDckAxfC22M5bTxosXwbrN1Vnht Ks61n7VZGXLlUlZGDH0CPQ8RVmKUqxfhssjrC1IPB6EVLFW/6TyuYW3Ah7qorXuSt97a FelZATKnKZ4KCa3LdAcnhajBQG3gpno5Ei1H6iVsFOMQ5CaHWYBaPr6qhRZwhuVFT+Y+ YtbA== X-Gm-Message-State: AMCzsaVz9vz+kzvCeymefWE3sanKr2s/WXCwt7bAN9RTlu4Wv8tQ0bZ6 9eym3oT0E0UZxN37fzmtVCcR4fXE X-Google-Smtp-Source: AOwi7QCfSACr0peMLWDBJx3eIygoktqSBax6ahQva+Ju5Fs96305YMSympnjorUdpywd0Y+rYp1pRw== X-Received: by 10.28.211.69 with SMTP id k66mr12100999wmg.1.1507011728568; Mon, 02 Oct 2017 23:22:08 -0700 (PDT) Received: from bens-mac.home (LFbn-MAR-1-445-220.w2-15.abo.wanadoo.fr. [2.15.38.220]) by smtp.gmail.com with ESMTPSA id v2sm7550275wmf.40.2017.10.02.23.22.07 (version=TLS1 cipher=ECDHE-RSA-AES128-SHA bits=128/128); Mon, 02 Oct 2017 23:22:07 -0700 (PDT) Content-Type: text/plain; charset=us-ascii Mime-Version: 1.0 (Mac OS X Mail 9.3 \(3124\)) Subject: Re: ZFS stalled after some mirror disks were lost From: Ben RUBSON In-Reply-To: Date: Tue, 3 Oct 2017 08:22:06 +0200 Cc: Steven Hartland , Freebsd fs , FreeBSD-scsi Content-Transfer-Encoding: quoted-printable Message-Id: References: <4A0E9EB8-57EA-4E76-9D7E-3E344B2037D2@gmail.com> To: Andriy Gapon X-Mailer: Apple Mail (2.3124) X-BeenThere: freebsd-scsi@freebsd.org X-Mailman-Version: 2.1.23 Precedence: list List-Id: SCSI subsystem List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Tue, 03 Oct 2017 06:22:10 -0000 > On 03 Oct 2017, at 08:12, Andriy Gapon wrote: >=20 > On 02/10/2017 21:12, Ben RUBSON wrote: >> A sustained read throughput of 180 MB/s, 45 MB/s on each iscsi disk >> according to "zpool iostat", nothing on local disks (strange but I >> noticed that IOs always prefer iscsi disks to local disks). >=20 > Are your local disks SSD or HDD? HDD. > Could it be that iSCSI disks appear to be faster than the local disks = to the > smart ZFS mirror code? Or because their /dev/da are greater then the local ones ? (as they are attached after the local disks) (my 2 cents...) For sure we could have expected the local disks to be preferred, or at least the load to be spread among all (local & iscsi) disks. > Steve, what do you think?