Gentoo Archives: gentoo-user

From: Dale <rdalek1967@×××××.com>
To: gentoo-user@l.g.o
Subject: Re: [gentoo-user] External hard drive and idle activity
Date: Tue, 11 Aug 2020 13:28:16
Message-Id: f082bc95-fd5e-e5fa-b7f4-0c7364a60cfe@gmail.com
In Reply to: Re: [gentoo-user] External hard drive and idle activity by Wols Lists
1 Wols Lists wrote:
2 > On 04/08/20 08:42, Wols Lists wrote:
3 >> Both LVM and btrfs offer snapshotting, so you take a snapshot before
4 >> doing an in-place rsync, giving you one full backup per snapshot, but
5 >> the drive is actually only storing the changes between snapshots.
6 >> Probably run the backup much faster too.
7 > Just strikes me this would be near ideal for an SMR drive, because this
8 > would be copy-on-write, so the backup would just be streaming new data
9 > to disk.
10 >
11 > And by judiciously choosing when to delete snapshots, you have
12 > considerable control over when the drive decides to do a defrag.
13 >
14 > Cheers,
15 > Wol
16 >
17 >
18
19
20 I've never used those features of LVM before.  Most likely, I should. 
21 I've had occasion to do a backup and then wish I had a old file back
22 that was deleted during the new backup process.  Example.  I have a copy
23 of a video for a particular show.  I find a better version, HD or
24 something, and download it.  I then remove the old one and find out
25 shortly after that it's the wrong episode or something.  At that point,
26 I'm missing a episode.  I'd rather have a standard definition version
27 than none at all.  I suspect doing it the way you mention I'd be able to
28 get that old copy back provided that snapshot hasn't been deleted yet. 
29 The way I do it now, once I update the backups, old stuff is deleted. 
30
31 Also, I just did another fairly large update on the backups.  Once it
32 hit around 50GBs or so, it started slowing down again.  It was even
33 slower than last time.  It was transferring at around 70MBs/sec.  Of
34 course, it could be partly because that drive is filling up.  It's
35 around 80% or so. 
36
37 Anyway.  I need to look into the snapshot thing.  Gotta find a howto.  ;-)
38
39 Dale
40
41 :-)  :-)