[PLUG] How to restore external drive

[Tomas K]

A few comments...

> However, I have long been impatient with the speed of the Mediasonic;
> moving or renaming a file can take over a minute while the drives
> whir and the lights dance.

Renaming or moving files on the same drive should take fraction of a
second regardless of the file size or the speed of connection to it. If
this what you really experience, you should consider using mv on a
command line.

> During the restore from backup the GUI (Nautilus) gave me a popup
> with continuous information on the progress, and it reported a steady
> 115-116 Mbps transfer rate, so that is apparently the max that my
> home ethernet can do.

That 100-120MBs is about maximum you can observe over 1Gbs ethernet to
a NAS for sequential, large file transfers. Recent Synology NAS`s are
capable of that without problem even for RAID5 arrays.

Please note - sequential, large file transfers - is the keyword.
Once we talk about random or small file access - you are into 40MBs-ish 
territory even for fast SSDs - no what the speed of connection.

See some benchmarks such as:
SSDs: https://www.anandtech.com/show/12485/the-plextor-m8v-sata-ssd-rev
iew/5
NVMEs: https://www.anandtech.com/show/13254/the-toshiba-xg6-1tb-ssd-rev
iew-first-96l-3d-nand/5

> Thinkpad P72 (not yet available in the US) or a P71 that I can buy
> right now. Both come with Intel Thunderbolt 3 USB-C ports that are
> capable of 40Gbps, compared to the 5Gbps of my USB 3.0 connection or
> 3GBps of eSATA.

So, connecting to HDD or SSD from single user, single computer at 5Gbs,
10Gbs or even 40Gbs is rather irrelevant. Especially when you consider
a laptop which is very limited in what it is capable of compared to a
desktop - especially in high bandwidth usage applications.

Anyway - large files are mainly media - Encoding a film with x264
proceeds at glacial 5Mbs-ish speed these days. So even if you could
encode 5 streams at the same time, you would probably be fine with 1Gbs
ethernet to a NAS.

Backups are incremental, and do not slow you down, especially if your
NAS writes to your DAS directly or between two NAS`s. I assume that you
are not watching the backups to make them go faster. :-)

--- If we would be talking (= not dreaming) about low cost 4-6
drive Synology NAS with 2.5/5/10Gbs ethernet + $150-ish 8 port
2.5/5/10Gbs switch to go with it - that would be different cup-a-tea.
---

Storage is slow, and who likes politics or taxes.

Hope it helps, Tomas

On Mon, 2018-10-15 at 08:39 -0700, John Jason Jordan wrote:
> On Mon, 15 Oct 2018 01:27:31 -0700
> Tomas K <tomas.kuchta.lists at gmail.com> dijo:
> 
> > It seems that it would be safer to have the DAS array attached
> > permanently to your NAS and access it over the network. That is if
> > your
> > NAS has eSATA port.
> > 
> > That way it would be permanently attached like internal drives and
> > that
> > should avoid these type of synchronization errors - Especially when
> > you
> > use it as RAID0.
> > 
> > RAID arrays, especially in striping configuration, do not like to
> > be
> > detached or put to sleep without proper sync and umount.
> 
> The Synology NAS does not have an eSATA port, but it does have a USB
> port, so I could probably attach the Mediasonic to it. And I agree
> that
> doing so might make the connection more stable - the NAS is across
> the
> room, while the Mediasonic is on my desk where stuff gets moved
> around
> a bit. However, I have long been impatient with the speed of the
> Mediasonic; moving or renaming a file can take over a minute while
> the
> drives whir and the lights dance. I lust for SSDs to replace the two
> WD
> Red Pro drives in it, but the cost of 16TB of SSDs always makes me
> discard the notion. If I attach the Mediasonic to the Synology I
> wonder
> about access time compared to its current USB 3 connection. 
> 
> During the restore from backup the GUI (Nautilus) gave me a popup
> with
> continuous information on the progress, and it reported a steady 115-
> 116
> Mbps transfer rate, so that is apparently the max that my home
> ethernet
> can do.
> 
> I have been shopping for a new computer and I'm currently looking at
> a
> Thinkpad P72 (not yet available in the US) or a P71 that I can buy
> right now. Both come with Intel Thunderbolt 3 USB-C ports that are
> capable of 40Gbps, compared to the 5Gbps of my USB 3.0 connection or
> 3GBps of eSATA. Then again, the WD Red Pro drives are SATA-3, which
> are
> rated at 6Gbps, so until I go to SSDs there wouldn't be much to gain.
> And the only faster enclosures available are Mediasonic rated at
> 10Gbps. What would be really cool is 16TB of SSDs mounted inside the
> laptop itself. 
> 
> > If attaching it permanently to NAS is not an option, autofs with
> > reasonable timeout avoiding the DAS power saving mode, instead of
> > mount
> > in fstab, would probably help too.
> 
> The Synology is mounted by a line in fstab, but not the Mediasonic. I
> have thought of doing so, but haven't bothered; it's trivial to mount
> it with the GUI. But if doing so can increase access speed I'm all
> for
> it. 
> _______________________________________________
> PLUG mailing list
> PLUG at pdxlinux.org
> http://lists.pdxlinux.org/mailman/listinfo/plug