lubuntu-qa team mailing list archive

[Jonathan Marsden <jmarsden@xxxxxxxxxxx>]

On 03/31/2013 04:13 AM, prairie zephyr wrote:

> I have been trying to test as many ppc images as I can.

Thankyou, thankyou, thankyou! :)  We need more people like you!

> I noticed zsync read 49% of the seed file was good before it started
> overwriting the alt lubuntu, even inside it's own folder. There may
> be a good reason to name every beta, alpha, daily flavour test
> release for ppc "raring-desktop-powerpc.iso" (under non-testing 
> conditions zsync would have saved 49% ...

> Am I missing something?

Perhaps!

I don't see the 49% similarity between amd64 desktop and amd64 alternate
images that you are seeing between powerpc desktop and powerpc alternate
images, I am seeing around 3%, which is not really enough to make it
worthwhile... but if there is a lot of similarity, zsync is your friend.

You can easily keep your images in separate folders, named however you
prefer.  zsync has useful options.  man zsync for the details.

In particular, -i tells zsync about additional input files it can use,
and -o specifies a desired output file name.  So, for example, you can do

  zsync -o raring-alternate-powerpc.iso http://whatever...

and then later you can do

  zsync -i raring-alternate-powerpc.iso -o raring-desktop-powerpc.iso
http://whateverelse...

You can use paths including folder names with -i and -o, too, if you
want to.  Or even use -i multiple times to read multiple different input
files, if that makes sense for your needs.

This way, the ISO file names on your local disk stay distinct, and make
sense to you, but zsync will use whatever pieces are the same in the
input file(s) when it syncs the second image for you, saving you
bandwidth and time.

Best of both worlds!

I know, this is not 100% obvious, especially for those who don't read
the man pages.  They are often worth reading :)

Jonathan