From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from lists.gentoo.org (pigeon.gentoo.org [208.92.234.80]) by finch.gentoo.org (Postfix) with ESMTP id 1F50113881D for ; Sat, 26 Sep 2015 15:21:44 +0000 (UTC) Received: from pigeon.gentoo.org (localhost [127.0.0.1]) by pigeon.gentoo.org (Postfix) with SMTP id 5E60921C0AF; Sat, 26 Sep 2015 15:21:32 +0000 (UTC) Received: from mail-ig0-f176.google.com (mail-ig0-f176.google.com [209.85.213.176]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by pigeon.gentoo.org (Postfix) with ESMTPS id 58B78E0885 for ; Sat, 26 Sep 2015 15:21:31 +0000 (UTC) Received: by igcpb10 with SMTP id pb10so30084108igc.1 for ; Sat, 26 Sep 2015 08:21:30 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20120113; h=mime-version:sender:in-reply-to:references:date:message-id:subject :from:to:content-type:content-transfer-encoding; bh=8uTTB92Yg/04zjP16Aoik1bkjfKrMtahzcfJwVVK8wc=; b=wpne1VKVlUqt5EsYLz1PBGtCCwKnjnQUhiwVCQfeAA+voi2n2A7DZwTQ5Wc7u7v3W2 0tyJOGwAF0i8+fNcmXDSlC5ohNgVzqfDOP8HKeoPfqzjVwfBdQui9mTzkaQiZdhbX956 yH+e1m9CBjYwWD0/oiGfq4bz9HKgVmDsZ1vZrVTepGbIOlL3mNxiu3nMRBhCG0gOeQfG gX3ETvYAQ2QbL4XXwWwCIf50Er7/Il2x5/3jsGUy/2nkKiftbg9Dbj6TtWeHn+zXxp2j ezirKJUQTuzh3wiWuCEs5wwUJ+YMYebMXXMydoJpL2+S69GWXo0JxrJl76xXOpZ3kuuW atJw== Precedence: bulk List-Post: List-Help: List-Unsubscribe: List-Subscribe: List-Id: Gentoo Linux mail X-BeenThere: gentoo-user@lists.gentoo.org Reply-to: gentoo-user@lists.gentoo.org MIME-Version: 1.0 X-Received: by 10.50.45.10 with SMTP id i10mr7504740igm.70.1443280890377; Sat, 26 Sep 2015 08:21:30 -0700 (PDT) Sender: freemanrich@gmail.com Received: by 10.79.103.70 with HTTP; Sat, 26 Sep 2015 08:21:30 -0700 (PDT) In-Reply-To: References: <20150926080824.GA4550@lira> Date: Sat, 26 Sep 2015 11:21:30 -0400 X-Google-Sender-Auth: fbTK8K_dACY8JOpdZhUnc-L-71g Message-ID: Subject: Re: [gentoo-user] Re: Dynamically change PORTAGE_TMPDIR via bashrc? From: Rich Freeman To: gentoo-user@lists.gentoo.org Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: quoted-printable X-Archives-Salt: 43409d8c-1655-4d1f-9fea-5e27d907dc9b X-Archives-Hash: b57bec5f2e3e7fdc0f060f3f6199ce1a On Sat, Sep 26, 2015 at 10:08 AM, James wrote: > Florian Gamb=C3=B6ck floga.de> writes: >> Now, before I try some crazy stunts like bind-mounting $D and $ED on "pr= einst" >> and cleaning up in "postinst", I wanted to know if some of you guys did >> similar experiments and/or have some advice that you could share with me= . > > I have been following 'bcache' as an interesting addition to complex > compiling scenarios. I'm not certain how it will help your 'wild ideas', > but it is worth a look, imho [1] Honestly, I'm hard-pressed to think of situations where you're better off with anything other than either tmpfs or whatever filesystem your /usr happens to be on. However, if you do want to build on something like bcachefs and you're using an ssd you might just want to use a pure log-based filesystem like f2fs. You can afford to go far more experimental for temp space. I haven't studied the design of bcachefs closely, so I'm not sure how it would compare for this use. I know it has made a bunch of noise lately, though honestly I'm not impressed with some of the hype (not something I blame the authors for - more the groupies). One thing that both zfs and bcachefs seem to be doing (not that I'm in an expert in either) is taking a multi-tiered approach to storage. That is, writes can go into a durable log on a separate device and then be consolidated onto more long-term storage. I suspect that this might help with some of the fragmentation issues that you run into with COW. Then again, I don't know how its performance would compare to just dumping everything right to a single tier like btrfs and then just periodically having some kind of smart defragmenter that just cleans up the stuff that really needs it. --=20 Rich