Groups > linux.debian.user > #171980

Re: Debian server for backups of Windows clients

From	Dan Ritter <dsr@randomstring.org>
Newsgroups	linux.debian.user
Subject	Re: Debian server for backups of Windows clients
Date	2016-09-10 14:50 +0200
Message-ID	<sfPTj-it-21@gated-at.bofh.it> (permalink)
References	(5 earlier) <s4qYh-74Q-1@gated-at.bofh.it> <sfzbP-6zJ-1@gated-at.bofh.it> <sfHj3-3hP-7@gated-at.bofh.it> <sfHVM-3Om-19@gated-at.bofh.it> <sfJ1w-4tC-3@gated-at.bofh.it>
Organization	linux.* mail to news gateway

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On Sat, Sep 10, 2016 at 01:22:45AM -0400, Neal P. Murphy wrote:
> On Fri, 9 Sep 2016 23:14:30 -0500
> David Wright <deblis@lionunicorn.co.uk> wrote:
> 
> Good eye! I was going to say it's not possible to get 110Mb/s over 802.11g; 40-50 is closer tothe best I get. And 193Mb/s over 100Mb/s ethernet is right out; best I've ever managed is maybe 97Mb/s, and 92-95 is more typical. 11,034,157Mb/s on W/L and 19,338,838Mb/s on wired is *much* more believable.
> 
> Unless one has a very fast multicore CPU with hardware crypto assistance, very fast RAM and the data to be transferred cached in RAM, one will probably never saturate a fastE or gigE link where one end must decrypt the data from disk/cache then encrypt the data to scp, and the other end must decrypt the data from scp then encrypt the data to disk. Even simple compression slows transfer down far too much.

SSDs can routinely read 400-600 MB/s. No need to have everything
cached in RAM.

In 2010, the first generation of i5 CPUs with hardware support for AES
could encrypt at about 15 MB/s, more than filling a 100 Mb/s pipe.

Here's a table of recent CPUs with AES support, running with
OpenSSL/LibreSSL. https://calomel.org/aesni_ssl_performance.html

It's in megabytes per second, so assume 1000/8 = 250 MB/s is the
bandwidth of a gigabit ethernet NIC. Anything which can do 2x
that can approach encrypting/decrypting from SSD, then
decrypting/encrypting over an SSH connection.

There are a lot of 500s and above on that chart.

And that's per-core, so even the 250+ CPUs can fill a gig-e pipe
while reading from SSD.

Nor are they monstrously expensive: an AMD FX-6300 is $90, a
motherboard for it could be another $90, and you can get a
decent SSD for $100 these days. A $400 desktop can be put
together that can saturate a gig-E link with encrypted traffic
from an encrypted disk.

Truly we live in marvelous times.

-dsr-

Thread

Debian server for backups of Windows clients Daniel Bareiro <daniel-listas@gmx.net> - 2016-08-02 23:20 +0200
  Re: Debian server for backups of Windows clients David Christensen <dpchrist@holgerdanske.com> - 2016-08-03 05:30 +0200
    Re: Debian server for backups of Windows clients Daniel Bareiro <daniel-listas@gmx.net> - 2016-08-08 20:30 +0200
      Re: Debian server for backups of Windows clients David Christensen <dpchrist@holgerdanske.com> - 2016-08-09 05:30 +0200
        Re: Debian server for backups of Windows clients Daniel Bareiro <daniel-listas@gmx.net> - 2016-08-10 01:30 +0200
          Re: Debian server for backups of Windows clients David Christensen <dpchrist@holgerdanske.com> - 2016-08-10 04:00 +0200
            Re: Debian server for backups of Windows clients Celejar <celejar@gmail.com> - 2016-09-09 21:00 +0200
              Re: Debian server for backups of Windows clients Daniel Bareiro <daniel-listas@gmx.net> - 2016-09-09 21:50 +0200
                Re: Debian server for backups of Windows clients Celejar <celejar@gmail.com> - 2016-09-09 23:20 +0200
                Re: Debian server for backups of Windows clients Daniel Bareiro <daniel-listas@gmx.net> - 2016-09-11 14:30 +0200
                Re: Debian server for backups of Windows clients deloptes <deloptes@gmail.com> - 2016-09-10 00:10 +0200
                Re: Debian server for backups of Windows clients Daniel Bareiro <daniel-listas@gmx.net> - 2016-09-11 14:10 +0200
              Re: Debian server for backups of Windows clients David Christensen <dpchrist@holgerdanske.com> - 2016-09-10 05:40 +0200
                Re: Debian server for backups of Windows clients David Wright <deblis@lionunicorn.co.uk> - 2016-09-10 06:20 +0200
                Re: Debian server for backups of Windows clients "Neal P. Murphy" <neal.p.murphy@alum.wpi.edu> - 2016-09-10 07:30 +0200
                Re: Debian server for backups of Windows clients Dan Ritter <dsr@randomstring.org> - 2016-09-10 14:50 +0200
                Re: Debian server for backups of Windows clients rhkramer@gmail.com - 2016-09-10 16:30 +0200
                Re: Debian server for backups of Windows clients Gene Heskett <gheskett@shentel.net> - 2016-09-10 16:50 +0200
                Re: Debian server for backups of Windows clients rhkramer@gmail.com - 2016-09-10 17:00 +0200
                Re: Debian server for backups of Windows clients David Christensen <dpchrist@holgerdanske.com> - 2016-09-10 17:40 +0200
                Re: Debian server for backups of Windows clients Gene Heskett <gheskett@shentel.net> - 2016-09-10 19:40 +0200
                Re: Debian server for backups of Windows clients "Neal P. Murphy" <neal.p.murphy@alum.wpi.edu> - 2016-09-11 07:50 +0200
                Re: Debian server for backups of Windows clients David Christensen <dpchrist@holgerdanske.com> - 2016-09-10 08:20 +0200
                Re: Debian server for backups of Windows clients Celejar <celejar@gmail.com> - 2016-09-11 04:30 +0200
            Re: Debian server for backups of Windows clients Daniel Bareiro <daniel-listas@gmx.net> - 2016-09-09 21:50 +0200
              Re: Debian server for backups of Windows clients David Christensen <dpchrist@holgerdanske.com> - 2016-09-10 05:50 +0200
                Re: Debian server for backups of Windows clients Celejar <celejar@gmail.com> - 2016-09-11 04:30 +0200
                Re: Debian server for backups of Windows clients David Christensen <dpchrist@holgerdanske.com> - 2016-09-11 05:10 +0200
  Re: Debian server for backups of Windows clients didier gaumet <didier.gaumet@gmail.com> - 2016-08-03 10:40 +0200
    Re: Debian server for backups of Windows clients Daniel Bareiro <daniel-listas@gmx.net> - 2016-08-10 01:40 +0200
      Re: Debian server for backups of Windows clients didier gaumet <didier.gaumet@gmail.com> - 2016-08-11 18:50 +0200
        Re: Debian server for backups of Windows clients didier gaumet <didier.gaumet@gmail.com> - 2016-08-11 19:00 +0200
  Re: Debian server for backups of Windows clients Darac Marjal <mailinglist@darac.org.uk> - 2016-08-08 11:10 +0200
    Re: Debian server for backups of Windows clients Daniel Bareiro <daniel-listas@gmx.net> - 2016-08-08 22:10 +0200
      Re: Debian server for backups of Windows clients David Christensen <dpchrist@holgerdanske.com> - 2016-08-09 05:30 +0200
        Re: Debian server for backups of Windows clients Mike McGinn <mikemcginn@mcginnweb.net> - 2016-08-09 15:40 +0200
    Re: Debian server for backups of Windows clients Glenn English <ghe@slsware.net> - 2016-08-08 23:40 +0200
      Re: Debian server for backups of Windows clients Daniel Bareiro <daniel-listas@gmx.net> - 2016-08-09 03:20 +0200
  Re: Debian server for backups of Windows clients Joel Wirāmu Pauling <joel@aenertia.net> - 2016-08-10 02:20 +0200

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