From owner-freebsd-geom@FreeBSD.ORG Fri Oct 17 12:04:58 2014 Return-Path: Delivered-To: freebsd-geom@freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [8.8.178.115]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by hub.freebsd.org (Postfix) with ESMTPS id DFFEF670 for ; Fri, 17 Oct 2014 12:04:57 +0000 (UTC) Received: from mail-ie0-f169.google.com (mail-ie0-f169.google.com [209.85.223.169]) (using TLSv1 with cipher ECDHE-RSA-RC4-SHA (128/128 bits)) (Client CN "smtp.gmail.com", Issuer "Google Internet Authority G2" (verified OK)) by mx1.freebsd.org (Postfix) with ESMTPS id B135CDF8 for ; Fri, 17 Oct 2014 12:04:57 +0000 (UTC) Received: by mail-ie0-f169.google.com with SMTP id tp5so579122ieb.14 for ; Fri, 17 Oct 2014 05:04:51 -0700 (PDT) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20130820; h=x-gm-message-state:mime-version:date:message-id:subject:from:to :content-type; bh=WU6RvMs84/3ZNrGeeenHvROHr/UCI2ZHDrBsaRh/iBc=; b=mzWj3XL5GwL28KuvyMmWC60SH2BDJXLVM1RUW3FOlw0SIseIRFzpW4Maj43KgEXfiS 8KLRjiZ8qlQOgUbNXlALWQ3EIBkHNEOzxKWlf41evSfpqpgJMPa5vSXNAf+AfWq67vQr 11rQnerRp36biJoOkcF+VSfOSNUedvMiO+G9snM+YM6pv6oN61H5jdqz9y9/X8lkmVUI DNqkwc4NZJfmsjjRxOHXG1WWm9zebD9vF4uWC/9Fz4w1dMPKNjNPWcRBzTBLmh1UjDI4 Oq39avhK956E71zX5ljpjYjhTM5i03F1vkXS6MTdmG4dIEqVnXVK/NtEZa1IbqrmnKqe lYUw== X-Gm-Message-State: ALoCoQn1A0SiwQMNVUcu8A2CrC5GIyBgJyhBf4bc2SWQRvImKxAFgCB7J0JjbkAMdJ66LzGfv5S8 MIME-Version: 1.0 X-Received: by 10.42.8.70 with SMTP id h6mr1253730ich.85.1413547489293; Fri, 17 Oct 2014 05:04:49 -0700 (PDT) Received: by 10.107.9.8 with HTTP; Fri, 17 Oct 2014 05:04:49 -0700 (PDT) Date: Fri, 17 Oct 2014 17:34:49 +0530 Message-ID: Subject: geom gate network From: Sourish Mazumder To: freebsd-geom@freebsd.org Content-Type: text/plain; charset=UTF-8 X-Content-Filtered-By: Mailman/MimeDel 2.1.18-1 X-BeenThere: freebsd-geom@freebsd.org X-Mailman-Version: 2.1.18-1 Precedence: list List-Id: GEOM-specific discussions and implementations List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Fri, 17 Oct 2014 12:04:58 -0000 Hi, I am planning to use geom gate network for accessing remote disks. I set up geom gate as per the freebsd handbook. I am using freebsd 9.2. I am noticing heavy performance impact for disk IO when using geom gate. I am using the dd command to directly write to the SSD for testing performance. The IOPS gets cut down to 1/3 when accessing the SSD remotely over a geom gate network, compared to the IOPS achieved when writing to the SSD directly on the system where the SSD is attached. I thought that there might be some problems with the network, so decided to create a geom gate disk on the same system where the SSD is attached. This way the IO is not going over the network. However, in this use case I noticed the IOPS get cut down to 2/3 compared to IOPS achieved when writing to the SSD directly. So, I have a SSD and its geom gate network disk created on the same node and the same IOPS test using the dd command gives 2/3 IOPS performance for the geom gate disk compared to running the IOPS test directly on the SSD. This points to some performance issues with the geom gate itself. Is anyone aware of any such performance issues when using geom gate network disks? If so, what is the reason for such IO performance drop and are there any solutions or tuning parameters to rectify the performance drop? Any information regarding the same will be highly appreciated. -- Sourish Mazumder Software Architect CloudByte Inc.