From mboxrd@z Thu Jan  1 00:00:00 1970
Return-Path: <linux-fsdevel-owner@vger.kernel.org>
Received: from mail-qk0-f195.google.com ([209.85.220.195]:38905 "EHLO
        mail-qk0-f195.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org
        with ESMTP id S1754780AbdJIPcK (ORCPT
        <rfc822;linux-fsdevel@vger.kernel.org>);
        Mon, 9 Oct 2017 11:32:10 -0400
Received: by mail-qk0-f195.google.com with SMTP id 17so9633967qkq.5
        for <linux-fsdevel@vger.kernel.org>; Mon, 09 Oct 2017 08:32:10 -0700 (PDT)
MIME-Version: 1.0
In-Reply-To: <150174646416.104003.14042713459553361884.stgit@hn>
References: <150174646416.104003.14042713459553361884.stgit@hn>
From: Miklos Szeredi <miklos@szeredi.hu>
Date: Mon, 9 Oct 2017 17:32:07 +0200
Message-ID: <CAELBmZAs6iAMx_0wxTnC7qrbMiQDDVG3dUtAhjeOKJ6ig2k6tQ@mail.gmail.com>
Subject: Re: [RFC 00/16] NOVA: a new file system for persistent memory
To: Steven Swanson <swanson@eng.ucsd.edu>
Cc: linux-fsdevel <linux-fsdevel@vger.kernel.org>,
        LKML <linux-kernel@vger.kernel.org>, linux-nvdimm@lists.01.org,
        Steven Swanson <steven.swanson@gmail.com>,
        dan.j.williams@intel.com, Steven Whitehouse <swhiteho@redhat.com>
Content-Type: text/plain; charset="UTF-8"
Sender: linux-fsdevel-owner@vger.kernel.org
List-ID: <linux-fsdevel.vger.kernel.org>

On Thu, Aug 3, 2017 at 9:48 AM, Steven Swanson <swanson@eng.ucsd.edu> wrote:
> This is an RFC patch series that impements NOVA (NOn-Volatile memory
> Accelerated file system), a new file system built for PMEM.

Hi,

Thanks for posting.

I read the paper and the design looks nice.  Then I  looked at the
patches, but could not find a place to start, nor something I could
actually try out.  So let me suggest some ways to make this more
reviewer/tester friendly:

1) try starting with something very simple yet working and supporting
the final layout
   - no optimizations (one big lock, no per-cpu data, rcu, numa, etc support)
   - no support for optional features (checksumming, NFS export, etc)
   - missing mandatory features (e.g. just readdir and getattr support)
   - try and get it down to <5k lines, preferably 2-3k

2) pointer to sources and instructions for trying it out without
special hardware

3) build on this minimal working version by
   - adding mandatory features
   - then adding optimizations

4) each patch should leave the tree in a compiling and working state
but should be small and easily reviewed

5) leave optional features and unimportant optimizations for a later
submission; try to make the patchset as small as you meaningfully can
(i.e. it should be fully working and demonstrate the capabilities and
performance, but nothing more).

Thanks,
Miklos