Gentoo Archives: gentoo-user

From: Bill Kenworthy <billk@×××××××××.au>
To: gentoo-user@l.g.o
Subject: Re: [gentoo-user] External hard drive and idle activity
Date: Thu, 02 Jan 2020 02:44:38
Message-Id: ef87511a-9824-7245-8247-012c7f830e2b@iinet.net.au
In Reply to: Re: [gentoo-user] External hard drive and idle activity by Dale
1 On 2/1/20 10:27 am, Dale wrote:
2 > Mick wrote:
3 >> On Thursday, 2 January 2020 00:09:14 GMT Dale wrote:
4 >>> Howdy,
5 >>>
6 >>> As some may recall, I have a 8TB external SATA hard drive that I do back
7 >>> ups on. Usually, I back up once a day, more often if needed. Usually I
8 >>> turn the power on, mount it, do the back ups, unmount and turn the power
9 >>> back off. Usually it is powered up for 5 minutes or so. When I unmount
10 >>> it tho, I sometimes notice it is still doing something. I can feel the
11 >>> mechanism for the heads moving. It has a slight vibration to it.
12 >>> Questions are, what is it doing and should I let it finish before
13 >>> powering it off? I'd assume that once it in unmounted, the copy process
14 >>> is done so the files are safe. I guess it is doing some sort of
15 >>> internal checks or something but I'm not sure.
16 >> There is some delay with data still in the buffers between rsync/cp/tar/what-
17 >> ever saying it's finished on your terminal and the drive itself finishing
18 >> storing the data on the platters.
19 >>
20 >> If you look at vmstat, or keep an eye on Gkrelm you'll see what I mean.
21 >> Normally, if you try to unmount a drive while it is still being written to,
22 >> the umount/udisks command will complain the drive is busy.
23 >>
24 > When it does it for a somewhat short period of time, I can understand
25 > that.  It's one reason I try to leave it on when it "feels" that it is
26 > still busy.  Thing is, there are times when it goes on for 30 minutes or
27 > more.  At those times, even a USB stick should be done.  One would think
28 > at least.  It makes me curious as to what it is doing in that case.
29 > Still, I'd rather the unmount command force a wait until it is done.
30 > Honestly, I wouldn't want a drive or software that says something is
31 > done when it isn't.  It's not good even when shutting a system down.
32 > Given the speed of drives, I would think a few seconds at most.  Best to
33 > be safe.  ;-)  I just wonder, is it doing two different things?  One
34 > when it is busy for short periods of time and something else when it
35 > goes on for a while.  This is what sort of puzzles me.  Selftest maybe??
36 >
37 >>> Is it safe to turn it off even tho it is doing whatever it is doing?
38 >>> Should I wait? Does it matter?
39 >>>
40 >>> Thanks.
41 >>>
42 >>> Dale
43 >>>
44 >>> :-) :-)
45 >> If you wait for a few seconds after the backup is completed before you unmount
46 >> the drive, you should be OK. Although it may slow down or any LEDs flash less
47 >> frequently the drive may not stop spinning, unless there is some power save
48 >> process taking control of it.
49 >>
50 > Given the speed, it is likely done when I tell the KDE thingy to
51 > unmount.  Usually, I start the backup and walk away for a few minutes.
52 > I do it with one of my scripts, if one can call what I do a script, and
53 > it does the date command at the end.  Even if there was a lot of
54 > changes, I can tell how long it was completed.  I try to give it a
55 > couple minutes.  Still, good point.  This is one reason I'm asking about
56 > this.  It's hard to know exactly what is going on here.
57 >
58 >>> P. S. Down to last router that was discussed in another thread so I
59 >>> bought it while they had it. Price may go up if I didn't. Did more
60 >>> research on old modem, it is risky to try to convert to AT&T. Some say
61 >>> not possible.
62 >> Right, ISP controlled firmware typically requires re-flashing the device with
63 >> the new ISP's firmware version. In some cases even the boot code needs
64 >> replacing. Should you flash the router with a wrong firmware build, you could
65 >> sometimes derive a door stop without additional cost. In this case you'll
66 >> need a JTAG and access to its circuit board with an OEM boot/firmware version
67 >> to recover it. In most cases OEMs support lines will redirect you to your
68 >> ISP, who run an overseas support line and will ask you to reboot your
69 >> MSWindows PC ... O_o
70 >>
71 >> This is a reason I avoid these kind of routers as much as I can.
72 >>
73 > Keep in mind, two pieces of hardware.  Router for the first two
74 > sentences and Modem for next two.  Tried to be short so . . . . Anyway,
75 > router should be flashable with Openwrt.  It's a slightly older model.
76 > New model may be ready for flashing in a year or two but not so much at
77 > the moment so I went with the older model. The modem, I never could find
78 > the firmware.  I found links to it but those links ended up being dead.
79 > Even if I had it, it was unlikely to work.  Possible but I'd be
80 > concerned about its stability and such even if it did take it. I have a
81 > modem and router on the way.  I just didn't want to miss the deal on the
82 > router.  They had several a couple weeks or so ago.  I got the last
83 > one.  Waiting for their arrival.
84 >
85 > Dale
86 >
87 > :-)  :-)
88 >
89 > Oh, I may post and see if anyone needs a Frontier modem later.  Maybe
90 > someone on here could use a spare or just needs one period, moving or
91 > something.  Modem is wireless with a router as well.  Nice modem I guess.
92 >
93
94 Try atop from sys-process/atop - it will show you how busy individual
95 disks are (and a lot of other stats as well.)
96
97 You can issue a sync command to flush any disk buffers before unmounting
98 (umounting should sync as well.).  The heads may keep moving because of
99 the internal data management modern disks do. The disks should be safe
100 to power off despite this (they have an internal flush/save/park routine
101 on power loss, with enough energy stored to take care of it)
102
103 BillK

Replies

Subject Author
Re: [gentoo-user] External hard drive and idle activity Dale <rdalek1967@×××××.com>
Re: [gentoo-user] External hard drive and idle activity Dale <rdalek1967@×××××.com>