Re: [Not TLS] Re: mount option nodatacow for VMs on SSD?

[Duncan <1i5t5.duncan@cox.net>]

Graham Cobb posted on Mon, 28 Nov 2016 09:49:33 +0000 as excerpted:

> On 28/11/16 02:56, Duncan wrote:
>> It should still be worth turning on autodefrag on an existing somewhat
>> fragmented filesystem.  It just might take some time to defrag files
>> you do modify, and won't touch those you don't, which in some cases
>> might make it worth defragging those manually.  Or simply create new
>> filesystems, mount them with autodefrag, and copy everything over so
>> you're starting fresh, as I do.
> 
> Could that "copy" be (a series of) send/receive, so that snapshots and
> reflinks are preserved?  Does autodefrag work in that case or does the
> send/receive somehow override that and end up preserving the original
> (fragmented) extent structure?

Very good question that I don't know the answer to as I've not seen it 
discussed previously.  (I'm not a dev, just a list regular and user of 
btrfs myself, and my personal use-case involves neither snapshots nor 
send/receive, so on those topics if I've not seen it covered previously 
either here or on the wiki, I won't know.)

Someone else know?

-- 
Duncan - List replies preferred.   No HTML msgs.
"Every nonfree program has a lord, a master --
and if you use the program, he is your master."  Richard Stallman