From owner-freebsd-questions@freebsd.org Tue Jan 2 19:52:56 2018 Return-Path: Delivered-To: freebsd-questions@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 12698EB603F for ; Tue, 2 Jan 2018 19:52:56 +0000 (UTC) (envelope-from amvandemore@gmail.com) Received: from mailman.ysv.freebsd.org (mailman.ysv.freebsd.org [IPv6:2001:1900:2254:206a::50:5]) by mx1.freebsd.org (Postfix) with ESMTP id E13116FF3D for ; Tue, 2 Jan 2018 19:52:55 +0000 (UTC) (envelope-from amvandemore@gmail.com) Received: by mailman.ysv.freebsd.org (Postfix) id DD8BFEB603E; Tue, 2 Jan 2018 19:52:55 +0000 (UTC) Delivered-To: questions@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 DAE65EB603D for ; Tue, 2 Jan 2018 19:52:55 +0000 (UTC) (envelope-from amvandemore@gmail.com) Received: from mail-it0-x231.google.com (mail-it0-x231.google.com [IPv6:2607:f8b0:4001:c0b::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 9348D6FF3C for ; Tue, 2 Jan 2018 19:52:55 +0000 (UTC) (envelope-from amvandemore@gmail.com) Received: by mail-it0-x231.google.com with SMTP id r6so40527430itr.3 for ; Tue, 02 Jan 2018 11:52:55 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=mime-version:in-reply-to:references:from:date:message-id:subject:to :cc; bh=SsKv1k+z9+gki8EUXdbhS2pSOTKoJrm71b83tpRiT0Q=; b=cOtjZgXJ53Y58yjujk3xceNZ4Qg8SlJrbKPCKUhc7PfHULARx2hgTQ/FBYG8L/QQZi RyGvT0S1RI7b5pfRi6r2KlvRjxvL9di67mlQ+iePaueCwez4EoAmwKN/mf/b8wFYKmqu rmIbbk2vj7fvDX91anhq19hChghV9fWy6FzDCXuWpTeAeLqGsxYqbQr5lsJ+Z1vLxxx6 YGQK4KBFAV9MELSTAbY91tELE8QKu022GbyUjjRvmzvtJxEdznDGtXzXB4wAsh12ty7X YSXYErY5z+KGBpl6mODcO2hQ+lgrOfo7dxtyLKaQKdNDwiOPqPy5ISuXWsOGuINpt3it IMuA== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:mime-version:in-reply-to:references:from:date :message-id:subject:to:cc; bh=SsKv1k+z9+gki8EUXdbhS2pSOTKoJrm71b83tpRiT0Q=; b=au/alDDkUIT6Wogq92IEPsFBfoL0x2XkYaj7SJv3DObb5Phl4+19HvvWECQnGDuDva LnGMmjN0i9dur5T+S976s6W4QFO7I4xl5wULZ1uuB3B3XcBb7yG5O/jHWdYMum1BY0iR GG0/djEfjdcRla9MVtvjuU45dJAakEZIJuaNFRUxs9MOkaQCdBaP8rOyKwiBfLeDP46j FYnX0q/aFXf+k+eZDiw2lKSKA8KmXMeG6pzynuakJpQJENcTT0w6S5P3y5bCauzRbnvL 0UCnHbENMO74wh8g10uT8ad7/LLHonGW+UzlCy8WXldWplYp5gbePkmAfnxczKSG8KB/ vRkQ== X-Gm-Message-State: AKGB3mJyvgAPp7qOnQ4Iu3tZa5ux8IJKwVSin8l8yQt5PjS+1noZJmXk fo8aPq9rBaI87++RFraHfq9CttahpfZxU0tM2Eg= X-Google-Smtp-Source: ACJfBovKtQvoyWjYNPlZptwi9cY6xqn3h6RzAov78kjD0PxFbhCgvtTrJ01gbCRY1zfV4KPaSRXaH6/P9LiRfvz6530= X-Received: by 10.36.39.8 with SMTP id g8mr24534966ita.42.1514922774827; Tue, 02 Jan 2018 11:52:54 -0800 (PST) MIME-Version: 1.0 Received: by 10.2.180.34 with HTTP; Tue, 2 Jan 2018 11:52:54 -0800 (PST) In-Reply-To: References: From: Adam Vande More Date: Tue, 2 Jan 2018 13:52:54 -0600 Message-ID: Subject: Re: zpool fragmentation To: pete wright Cc: freebsd-questions Content-Type: text/plain; charset="UTF-8" X-Content-Filtered-By: Mailman/MimeDel 2.1.25 X-BeenThere: freebsd-questions@freebsd.org X-Mailman-Version: 2.1.25 Precedence: list List-Id: User questions List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Tue, 02 Jan 2018 19:52:56 -0000 On Tue, Jan 2, 2018 at 12:40 PM, pete wright wrote: > Hi there, > I was wondering how others here on the list deal with zpool > fragmentation. My general purpose laptop uses zroot, and I've noticed > over time fragmentation of my pool has grown to %42: > > $ zpool list > NAME SIZE ALLOC FREE EXPANDSZ FRAG CAP DEDUP HEALTH ALTROOT > zroot 230G 87.3G 143G - 42% 37% 1.00x ONLINE - > $ > > I guess I have two questions: > 1) is fragmentation generally bad, or just a fact of life for a system > with lots of churn? > Yes but impact also depends on pool config. > 2) if it is bad, are there any coping mechanisms people use to reduce > fragmentation? > Keep lots of free space. -- Adam