[mythtv-users] What is best filesystem for recordings?

[Stephen Worthington]

On Tue, 30 Jun 2015 20:33:28 +0200, you wrote:

>On 30/06/15 14:20, Andre Newman wrote:
>>
>> I’m interested in how you get on with the Archive drive, shingled tracks I believe? Not happy about buying a Seagate (ever again) but HGST start to launch some shingled archive drives too.
>Yeah. Me too about Seagate...but here in Poland, 8T archive has 
>unmatched $/GB. It is 20% lower that currently best in this class 4T drives.
>I was thinking over week: should I go with 8T from Seagate.
>I took risk :-p
>I copied already over 2.9T movies to this drive. It performs 
>surprisingly well with write speed: top is 120MB/s, avg 90-95MB/s.
>Unfortunately I didn't check speed sustainability - but I'm expecting 
>not good results here.
>Here are some details: 
>http://www.storagereview.com/seagate_archive_hdd_review_8tb
>But as this drive will be used _exclusively_ for movies (so practically 
>no rewrites) I believe it is good trade-off.

I bought one of these too, for the same reason.  I am using it for
storing recordings, but not for recording to.  I have set up a new
storagegroup ("archive") and that storagegroup is not used in any
recording rules.  So far I have manually moved all my oldest
recordings over onto it (4.6 Tbytes), and its sequential write speed
was excellent - over 120 Mbytes/s according to iotop.  However, now I
have watched and deleted a couple of those old recordings, I am
expecting to have it have to do some rewriting if it fills the space
that was used by those two files.  According to the reviews, the write
speed can go down to 0 bytes/s for some time when it does a big
rewrite.

I am planning on adding an option to my balance_storage.sh script to
allow designating a storagegroup as "archival" - it will then get
filled up completely to make more room on the drives used for
recording, before the script moves on to balancing the free storage on
the recording drives.

I just hope that Seagate's bad drives are the cheap desktop ones, and
these SMT drives do not have the same failure rate.  I had 5 (6?)
7200.11 1 Tbyte Seagate drives die young (including warranty
replacement drives), so I told the retailer that I would not accept
another 7200.11 as a replacement.  The 7200.12 I got at that point was
OK - it had a reasonable lifetime.  But the ST1500DM003 drive (1.5
Tbyte) that I also got as a replacement has now also got heaps of bad
sectors, even though its time in use is very low as I was using it for
recordings to take away with my laptop when on holiday, so it only got
used for a few days a year.

I also have a Seagate ST4000VN000 4 Tbyte "NAS" drive as a recording
drive, and so far it has worked well - 672 days power on time and no
sign of trouble.  But I would not buy another of them as it has a
nasty "click" sound when the heads move.  It is probably not louder
than my other drives (WD red and green), but its quality makes it
quite noticeable, and the MythTV box is in my bedroom where noise can
be a problem.