Date: Sun, 22 Aug 2021 17:48:13 -0600 From: Alan Somers <asomers@freebsd.org> To: George Michaelson <ggm@algebras.org> Cc: Ben RUBSON <ben.rubson@gmx.com>, freebsd-fs <freebsd-fs@freebsd.org> Subject: Re: ZFS on high-latency devices Message-ID: <CAOtMX2hRuh_9ZOOoQufNT2QG3Ui0S3rJq%2BL-ox2kxsq1oJMSMA@mail.gmail.com> In-Reply-To: <CAKr6gn0r8xG9HNGOFh1A_usU4tPAYezeZv1chOG_bBMqy_HtXw@mail.gmail.com> References: <YR4mY%2Bb6o7fBJqEN@server.rulingia.com> <023225AD-2A97-47C5-9FE4-3ABF1BFD66F1@gmx.com> <CAKr6gn0r8xG9HNGOFh1A_usU4tPAYezeZv1chOG_bBMqy_HtXw@mail.gmail.com>
next in thread | previous in thread | raw e-mail | index | archive | help
--00000000000053c29c05ca2e8922 Content-Type: text/plain; charset="UTF-8" mbuffer is not going to help the OP. He's trying to create a pool on top of a networked block device. And if I understand correctly, he's connecting over a WAN, not a LAN. ZFS will never achieve decent performance in such a setup. It's designed as a local file system, and assumes it can quickly read metadata off of the disks at any time. The OP's best option is to go with "a": encrypt each dataset and send them with "zfs send --raw". I don't know why he thinks that it would be "very difficult". It's quite easy, if he doesn't care about old snapshots. Just: $ zfs create <crypto options> pool/new_dataset $ cp -a pool/old_dataset/* pool/new_dataset/ -Alan On Sun, Aug 22, 2021 at 5:40 PM George Michaelson <ggm@algebras.org> wrote: > I don't want to abuse the subject line too much, but I can highly > recommend the mbuffer approach, I've used this repeatedly, BSD-BSD and > BSD-Linux. It definitely feels faster than SSH, since the 'no cipher' > options were removed, and in the confusion of the HPC buffer changes. > But, its not crypted on-the-wire. > > Mbuffer tuning is a bit of a black art: it would help enormously if > there was some guidance on this, and personally I've never found the > mbuffer -v option to work well: I get no real sense of how full or > empty the buffer "is" or, if the use of sendmsg/recvmsg type buffer > chains is better or worse. > > -G > > On Fri, Aug 20, 2021 at 6:19 PM Ben RUBSON <ben.rubson@gmx.com> wrote: > > > > > On 19 Aug 2021, at 11:37, Peter Jeremy <peter@rulingia.com> wrote: > > > > > > (...) or a way to improve throughput doing "zfs recv" to a pool with a > high RTT. > > > > You should use zfs send/receive through mbuffer, which will allow to > sustain better throughput over high latency links. > > Feel free to play with its buffer size parameters to find the better > settings, depending on your link characteristics. > > > > Ben > > > > > > --00000000000053c29c05ca2e8922--
Want to link to this message? Use this URL: <https://mail-archive.FreeBSD.org/cgi/mid.cgi?CAOtMX2hRuh_9ZOOoQufNT2QG3Ui0S3rJq%2BL-ox2kxsq1oJMSMA>