From owner-freebsd-fs@FreeBSD.ORG Wed Jan 30 20:59:19 2013 Return-Path: Delivered-To: freebsd-fs@freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:1900:2254:206a::19:1]) by hub.freebsd.org (Postfix) with ESMTP id 56498EAD for ; Wed, 30 Jan 2013 20:59:19 +0000 (UTC) (envelope-from toasty@dragondata.com) Received: from mail-ie0-x22f.google.com (mail-ie0-x22f.google.com [IPv6:2607:f8b0:4001:c03::22f]) by mx1.freebsd.org (Postfix) with ESMTP id F221E6AC for ; Wed, 30 Jan 2013 20:59:18 +0000 (UTC) Received: by mail-ie0-f175.google.com with SMTP id c12so1687626ieb.6 for ; Wed, 30 Jan 2013 12:59:18 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=dragondata.com; s=google; h=x-received:content-type:mime-version:subject:from:in-reply-to:date :cc:content-transfer-encoding:message-id:references:to:x-mailer; bh=cnUN69pWlUjCGxQg9jE+TzJzR5O+4orLIVM/h6z/A7U=; b=Cc3tS0JuX+tkIqPeXky9R/5+AQB69kVOHLPA8szy6+4ThBEScrvCd3F3g1ker8WB3q GWAnc5o2yIEnJo6aQGK6Ssks6g7lDUDLVLV1GeJ0qm2LUXCrNtLvG2w1PQ8B5rcmrSXL e76RZyZbm3+jLpmPTsJ4VG5iSWlUiwXSciDpA= X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20120113; h=x-received:content-type:mime-version:subject:from:in-reply-to:date :cc:content-transfer-encoding:message-id:references:to:x-mailer :x-gm-message-state; bh=cnUN69pWlUjCGxQg9jE+TzJzR5O+4orLIVM/h6z/A7U=; b=GTt2W43YcjtaORYRsleZg45/xnFXvNselPfeI6Nr2QbZTKnFDXmrwM5z8PFRkvLENx kE1WoPku4buWmvrJxdaYWqivYAlm6Sq6exPVedwhpPkFcmQ/rOT9W3NisAzcPOES3Tzj /egkFpIqtCWaFPIX4qzsHZe1mUJiywX8sXUgAMzbCIjkhwDBM7BX6LAa/lo6NM612NPf XVMwBzb2ezCrqCD0tHeP8uDPlWVRw1U1mONq4I+YL7Uyt6OOMfv+kzmDqvr0Uyci7lGA vzuOTL3dUCmVN4TfQfgtLH6QViXN6czCqQMtvphUeI9ZKqBgBRHp/CoQxDVS1VsY1Dbd GufA== X-Received: by 10.50.192.197 with SMTP id hi5mr4638121igc.45.1359579558523; Wed, 30 Jan 2013 12:59:18 -0800 (PST) Received: from vpn132.rw1.your.org (vpn132.rw1.your.org. [204.9.51.132]) by mx.google.com with ESMTPS id fa6sm3343316igb.2.2013.01.30.12.59.16 (version=TLSv1 cipher=ECDHE-RSA-RC4-SHA bits=128/128); Wed, 30 Jan 2013 12:59:17 -0800 (PST) Content-Type: text/plain; charset=windows-1252 Mime-Version: 1.0 (Mac OS X Mail 6.2 \(1499\)) Subject: Re: Improving ZFS performance for large directories From: Kevin Day In-Reply-To: <23E6691A-F30C-4731-9F78-FD8ADDDA09AE@gmail.com> Date: Wed, 30 Jan 2013 14:59:15 -0600 Content-Transfer-Encoding: quoted-printable Message-Id: References: <19DB8F4A-6788-44F6-9A2C-E01DEA01BED9@dragondata.com> <5267B97C-ED47-4AAB-8415-12D6987E9371@gmail.com> <47975CEB-EA50-4F6C-8C47-6F32312F34C4@dragondata.com> <23E6691A-F30C-4731-9F78-FD8ADDDA09AE@gmail.com> To: Nikolay Denev X-Mailer: Apple Mail (2.1499) X-Gm-Message-State: ALoCoQnkS+6kCreYGM448c9En3dGEp/g3iUGqVrmWf1fActc0Mdnx6jek0faAnU6k7bN8BfFSNBO Cc: FreeBSD Filesystems X-BeenThere: freebsd-fs@freebsd.org X-Mailman-Version: 2.1.14 Precedence: list List-Id: Filesystems List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Wed, 30 Jan 2013 20:59:19 -0000 On Jan 30, 2013, at 10:34 AM, Nikolay Denev wrote: >>=20 >> vfs.zfs.arc_meta_limit: 8199079936 >> vfs.zfs.arc_meta_used: 13965744408 >>=20 >> Full output of zfs-stats: [=85snipped=85] >=20 > Looks like you can try to increase arc_meta_limit to be let's say : = half of arc_max. (16398159872 in your case). >=20 >=20 Okay, will give this a shot on the next reboot too. Does anyone here understand the significance of "used" being higher than = "limit"? Is the limit only a suggestion, or are there cases where = there'a certain metadata that must be in arc, and it's particularly = large here? -- Kevin