From mboxrd@z Thu Jan 1 00:00:00 1970 From: Wolfgang Rosner Subject: Re: One way TCP bottleneck over 6 x Gbit tecl aggregated link // Kernel issue Date: Mon, 23 Mar 2015 14:54:57 +0100 Message-ID: <201503231454.57319.wrosner@tirnet.de> References: <201503210110.48980.wrosner@tirnet.de> <201503231005.02195.wrosner@tirnet.de> <8926B7EB-3EC1-404A-95BA-787DF248773E@netapp.com> Mime-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: QUOTED-PRINTABLE Cc: "netdev@vger.kernel.org" To: "Zimmermann, Alexander" Return-path: Received: from mail.tirnet.de ([217.7.138.221]:56348 "EHLO mail.tirnet.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752013AbbCWNzF convert rfc822-to-8bit (ORCPT ); Mon, 23 Mar 2015 09:55:05 -0400 In-Reply-To: <8926B7EB-3EC1-404A-95BA-787DF248773E@netapp.com> Content-Disposition: inline Sender: netdev-owner@vger.kernel.org List-ID: Am Montag, 23. M=C3=A4rz 2015 10:25:33 schrieben Sie: > Hi Wolfgang, > > > Am 23.03.2015 um 10:05 schrieb Wolfgang Rosner : > > > > Am Montag, 23. M=C3=A4rz 2015 03:33:17 schrieb Eric Dumazet: > >> On Mon, 2015-03-23 at 01:57 +0100, Wolfgang Rosner wrote: > >>> Are you ready to assist me on this track? > >> > >> First check if the problem is already solved, using this git tree = ? > >> > >> http://git.kernel.org/cgit/linux/kernel/git/davem/net.git > > > > Is it OK to use this 3.19 tag? > > https://kernel.googlesource.com/pub/scm/linux/kernel/git/davem/net.= git/+/ > >v3.19 > > > > > > I see that head is v4.0-rc4 > > I'm afraid that this might break other things. > > I think of aufs, which I need to get my clients nfsroot booted. > > probably you can take a look on OverlayFS (instead of aufs) which > was introduced in kernel 3.18 > > Alex Hi Alex, Thank you for the tip. But if it just were that easy as to have a look at it.... As far as I know, overlayfs only allows two layers, right? So for more complex trees, I could maybe stack them (so I hope). To do so, at least I had to redesign my complete script which builds th= e=20 nfsroot mimics as shown below. And as far as I could figure out, the representation of whiteouts is di= fferent=20 in aufs and in overlayfs. So I cannnot simply use my existing aufs bran= ches=20 and stack them by overlayfs, without breaking the file/ whiteout consis= tency,=20 or can I? However, when making the decision in favour of aufs, the udba ("user di= rect=20 branch access") feature (and lack thereof in overlayfs) was the main re= ason=20 not to go for overlayfs: > Changes to the underlying filesystems while part of a mounted overlay > filesystem are not allowed. If the underlying filesystem is changed, > the behavior of the overlay is undefined, ( from https://www.kernel.org/doc/Documentation/filesystems/overlayfs.t= xt ) Is this going to change in the foreseeable future? Are you aware of any plans to implement UDBA in overlayfs? If so, I would be glad to participate in testing. I could live without the udba feature for a limited test period. But I got used to the possibility to install packages in a package laye= r, fine=20 tune configuration in another layer and live test this on a parallel cl= uster=20 of 16 machines, without dropping off nfsroot each time. Maybe, part of this funcitonality can be replaced by btrfs snapshotting= =2E But nevertheless, it would end up as a comlepte redesign of my cluster = setup. Wolfgang Rosner #######################################################################= ##### This is how my aufs mounts look like: aufs-nfsroot-blade-001 on /cluster/nfs/nfsr/blade-001.crunchnet type au= fs=20 (rw,relatime,si=3D88a4f4d462df4343) 0 rw id=3D64 path=3D/cluster/node_roots/wheezy-HD-2015_02_21/co= w/cow_001 1 ro+wh id=3D65 path=3D/cluster/node_roots/wheezy-HD-2015_02_21= /config 2 ro+wh id=3D66 path=3D/cluster/node_roots/wheezy-HD-2015_02_21= /mask 3 ro+wh id=3D67 path=3D/cluster/node_roots/wheezy-HD-2015_02_21= /pkg_std 4 ro id=3D68 path=3D/cluster/node_roots/wheezy-HD-2015_02_21/ba= se xino: /tmp/.aufs.xino : (repeated 16 times) : aufs-nfsroot-blade-016 plus 3 admin layers (writable for each intermediary layer) root@cruncher:/cluster/etc/scripts/available# mount | grep aufs aufs-nfsroot-blade-001 on /cluster/nfs/nfsr/blade-001.crunchnet type au= fs=20 (rw,relatime,si=3D88a4f4d462df4343) aufs-nfsroot-blade-002 on /cluster/nfs/nfsr/blade-002.crunchnet type au= fs=20 (rw,relatime,si=3D88a4f4d3fe245343) aufs-nfsroot-blade-003 on /cluster/nfs/nfsr/blade-003.crunchnet type au= fs=20 (rw,relatime,si=3D88a4f4d3fe9c5343) aufs-nfsroot-blade-004 on /cluster/nfs/nfsr/blade-004.crunchnet type au= fs=20 (rw,relatime,si=3D88a4f4d467b53343) aufs-nfsroot-blade-005 on /cluster/nfs/nfsr/blade-005.crunchnet type au= fs=20 (rw,relatime,si=3D88a4f4d47db69343) aufs-nfsroot-blade-006 on /cluster/nfs/nfsr/blade-006.crunchnet type au= fs=20 (rw,relatime,si=3D88a4f4d4630bb343) aufs-nfsroot-blade-007 on /cluster/nfs/nfsr/blade-007.crunchnet type au= fs=20 (rw,relatime,si=3D88a4f4d4586cc343) aufs-nfsroot-blade-008 on /cluster/nfs/nfsr/blade-008.crunchnet type au= fs=20 (rw,relatime,si=3D88a4f4d458689343) aufs-nfsroot-blade-009 on /cluster/nfs/nfsr/blade-009.crunchnet type au= fs=20 (rw,relatime,si=3D88a4f4d3fda97343) aufs-nfsroot-blade-010 on /cluster/nfs/nfsr/blade-010.crunchnet type au= fs=20 (rw,relatime,si=3D88a4f4d3fe3be343) aufs-nfsroot-blade-011 on /cluster/nfs/nfsr/blade-011.crunchnet type au= fs=20 (rw,relatime,si=3D88a4f4d3fe8cb343) aufs-nfsroot-blade-012 on /cluster/nfs/nfsr/blade-012.crunchnet type au= fs=20 (rw,relatime,si=3D88a4f4d3fc90c343) aufs-nfsroot-blade-013 on /cluster/nfs/nfsr/blade-013.crunchnet type au= fs=20 (rw,relatime,si=3D88a4f4d4622fb343) aufs-nfsroot-blade-014 on /cluster/nfs/nfsr/blade-014.crunchnet type au= fs=20 (rw,relatime,si=3D88a4f4d3e2cc8343) aufs-nfsroot-blade-015 on /cluster/nfs/nfsr/blade-015.crunchnet type au= fs=20 (rw,relatime,si=3D88a4f4d0ca64e343) aufs-nfsroot-blade-016 on /cluster/nfs/nfsr/blade-016.crunchnet type au= fs=20 (rw,relatime,si=3D88a4f4d0ca92e343) aufs_pkg_std on /cluster/node_roots/wheezy-HD-2015_02_21/admount-pkg_st= d type=20 aufs (rw,relatime,si=3D88a4f4d46dced343) aufs_mask on /cluster/node_roots/wheezy-HD-2015_02_21/admount-mask type= aufs=20 (rw,relatime,si=3D88a4f4d3b0a2b343) aufs_config on /cluster/node_roots/wheezy-HD-2015_02_21/admount-config = type=20 aufs (rw,relatime,si=3D88a4f4d3fee4c343)