From owner-freebsd-stable@freebsd.org Tue Nov 29 14:50:05 2016 Return-Path: Delivered-To: freebsd-stable@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 4897AC5C0BD for ; Tue, 29 Nov 2016 14:50:05 +0000 (UTC) (envelope-from killing@multiplay.co.uk) Received: from mail-wm0-x22e.google.com (mail-wm0-x22e.google.com [IPv6:2a00:1450:400c:c09::22e]) (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 D80D71EEE for ; Tue, 29 Nov 2016 14:50:04 +0000 (UTC) (envelope-from killing@multiplay.co.uk) Received: by mail-wm0-x22e.google.com with SMTP id t79so189890110wmt.0 for ; Tue, 29 Nov 2016 06:50:04 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=multiplay-co-uk.20150623.gappssmtp.com; s=20150623; h=subject:to:references:from:message-id:date:user-agent:mime-version :in-reply-to; bh=l8/S3AD9wZqTxgqQIPxeXQkElgS3pz3PFDiqVkvPFt0=; b=qZgAFbrUpX4JGDdLJiRu/foWcjacQbeDazA6Xz2yxW4DD2z8XNZcXRmDrCSjA7yrSJ ac6o7DruoaOifEXVclaKUdg+8jBXGh83OCqhTc+udPnkYk2KNOrFnHQa1geBfkxQwMaJ w43FgtHSZUsG/lA1h7K6jGz4tvhqKosOxRNdS7VqJ3QIQDsc8II5uBEMAIT55NyZKPGv IRx7OaWrFJglXHuUykoc0MjlZoiSB9DQ4A3HdvHHI3/zb3bu9ldzZT1bj/QRsCduRnC8 LO0ElNTCNMEeIIPzs5lr0/nEvmmg5EMoY9+xqvsPOpnzf1r8jIgmlIH4VJ2Cr18lKc0b TDGw== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20130820; h=x-gm-message-state:subject:to:references:from:message-id:date :user-agent:mime-version:in-reply-to; bh=l8/S3AD9wZqTxgqQIPxeXQkElgS3pz3PFDiqVkvPFt0=; b=fMupHoJcTV4xRerRqkSX+UvYaHxP+y07WI0nkrHnOqWC/m/pv4qA4tpqh0N8UcPmIK TPfyaCq5q4fIw3kFGXC3JPRAm0snN0MPbSSCdXloNGGW2htSyuS0cPcK7B2NHH5rCLPF XFzbD9yBVu92lzLVuoHgfx04Z1D7LfkWkkm6s8M6tfmpmHdkL+s/OvKrczduI/6dnhcN omOdLX39Mlp/cVLLVJ/T9knNGqlAZR8rsFIXpq6Me5sTzIKZYBNi6F2js+KttOxHDPr8 KfFTs7WxznQAuhoMLTSt4OMpoP0c7FrfET+5bgPM61Wi/Qrk9yRGKW/hZv8gOkCI88vp c0GA== X-Gm-Message-State: AKaTC01U3yihk7lGnOs5isFmG5IAyweFjFS67UjNoGMVlCRpTMrapyMqzGsP96MejXK5VENZ X-Received: by 10.28.97.139 with SMTP id v133mr23594278wmb.117.1480431002294; Tue, 29 Nov 2016 06:50:02 -0800 (PST) Received: from [10.10.1.58] ([185.97.61.26]) by smtp.gmail.com with ESMTPSA id r138sm3196703wme.9.2016.11.29.06.50.01 for (version=TLS1_2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Tue, 29 Nov 2016 06:50:01 -0800 (PST) Subject: Re: Sandisk CloudSpeed Gen. II Eco Channel SSD vs ZFS = we're in hell To: freebsd-stable@freebsd.org References: <345ed411-1430-50f7-6887-5ac00d259fd9@norma.perm.ru> <553eff7a-0cd5-eea9-4acd-4bc770fa1baf@multiplay.co.uk> <583D74FE.8040402@norma.perm.ru> From: Steven Hartland Message-ID: <4a2d4074-3455-5edb-4682-f1d6b82022fa@multiplay.co.uk> Date: Tue, 29 Nov 2016 14:50:23 +0000 User-Agent: Mozilla/5.0 (Windows NT 10.0; WOW64; rv:45.0) Gecko/20100101 Thunderbird/45.5.0 MIME-Version: 1.0 In-Reply-To: <583D74FE.8040402@norma.perm.ru> Content-Type: text/plain; charset=windows-1252; format=flowed Content-Transfer-Encoding: 7bit X-Content-Filtered-By: Mailman/MimeDel 2.1.23 X-BeenThere: freebsd-stable@freebsd.org X-Mailman-Version: 2.1.23 Precedence: list List-Id: Production branch of FreeBSD source code List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Tue, 29 Nov 2016 14:50:05 -0000 On 29/11/2016 12:30, Eugene M. Zheganin wrote: > Hi. > > On 28.11.2016 23:07, Steven Hartland wrote: >> Check your gstat with -dp so you also see deletes, it may be that your >> drives have a very slow TRIM. >> > Indeed, I see a bunch of delete operations, and when TRIM disabled my > engineers report that the performance is greatly increasing. Is this it ? > Yep sounds like the TRIM on the disk is particularly poor. You can download, compile and run http://blog.multiplay.co.uk/dropzone/freebsd/ioctl-delete.c You can run with: ioctl-delete This will time and give you performance info with regards to delete requests. It uses raw BIO_DELETE commands to the device so eliminates filesystem latency (don't run on a device that's in use). You'll likely want to put some data on there though as often FW eliminates the delete if it will have no effect e.g. dd if=/dev/random of= bs=1m count=20480 Regards Steve