Diff file for new releases
Forum: DSL Ideas and Suggestions
Topic: Diff file for new releases
started by: b1ackmai1er
Posted by b1ackmai1er on Dec. 15 2007,13:35Hi Guys,
The great thing about DSL is that it is under constant development and improvement. I am always hungry for the latest release candidate.
The downside of this is that I am constantly downloading 50M ISO's.
Is it possible that new releases could come out as a diff file too.
For example, the shareware version of WinISO supports up to 100M ISO's for free.
It would be great if we could download the changed files/directories and drag them into WinISO and burn the updated ISO.
This could save heaps of bandwith and possibly reduce each update download to the 1M region. Great for us hardcore users and good for the download sites too.
Is this possible?
Downloading 4.2RC1 now!
Posted by b1ackmai1er on Dec. 15 2007,14:21Ahhh, I see, this is probably harder than it looks because the system is set up as a 47M file.
Oh well, seemed like a good idea.
Posted by ^thehatsrule^ on Dec. 15 2007,20:12Well, there are binary diff utilities. But I should think that it could be just faster to download a new release. You could try it out...
A better solution might be to open up the cloop file, apply whatever diffs to text files, replace binaries as needed, add/remove files as needed, then remake the cloop, and optionally the cd image. But again, it seems a bit complicated, and for other OS's you might need to use a vm or something along those lines.
Posted by clivesay on Dec. 16 2007,02:58There is the xdelta program that some distros are using to allow people to merge the latest release updates with a previous iso. Some of the Mepis group use it.
Posted by b1ackmai1er on Dec. 16 2007,09:26Great suggestion,
I downloaded and tried xdelta.
The diff file between dsl-4.1.iso and dsl-4.2RC1.iso was 40 Meg.
Not the dramatic improvement I was expecting.
Mind you, if I was still on dial-up I would think its great.
Posted by b1ackmai1er on Dec. 16 2007,09:35I tried running Xdelta just on the KNOPPIX cloop file but there was no significant improvement.
Looks like it would have to be done the hard way, as thehatsrule suggests.
Posted by b1ackmai1er on Dec. 16 2007,12:01I thought I would give this a try and put it on a torrent site.
< http://linuxtracker.org/browse.php?cat=104 >
Posted by clivesay on Dec. 16 2007,14:48I can't imagine the xdelta would be that large, unless Robert made som wholesale changes.
Maybe I'll take a peek in the Mepislovers forum and see exactyl how they are doing this.
Posted by lucky13 on Dec. 17 2007,19:53I've resisted commenting because I don't see the benefit of basically remastering ISOs with each release, but I'm curious why it would appeal to someone. I know there are people without broadband, but I think that's increasingly the exception to the rule. I'm just trying to understand the cost:benefit (50MB versus something that either comes on a DVD or stripped to fit on a CD) of it.
I especially don't understand this when I put it in perspective of 50MB of data. Most people don't give second thought about streaming video from youtube or downloading other multimedia content whether audio or video or images, usually at transfer rates much greater than required to download one 50MB ISO. Most people who visit youtube will stream much more than 50MB of video at any given time. Ten to thirteen MP3s is about one DSL ISO. I download at least that much in podcasts and other content daily. So what's a new ISO every couple weeks?
If you have bandwidth restrictions, there are probably other ways around it like if DSL were to offer a subscription so you could pay $X and receive each new ISO as released. There are already services where you can order cheap ISOs (not a plug) online if it's a problem and John already sells single DSL CDs:
< http://damnsmalllinux.org/cd.html >
Posted by clivesay on Dec. 17 2007,20:37Lucky13,
I just saw this as someone inquiring whether they could get just the changes over a connection such as dialup without having to grab 50mb. That is a very large file for dialup and many rural places in my area are suffering with dialup on noisy phonelines...eww! There is an entire subdivision that is built around a lake that can only get 28k connection. With xdelta, you get the patch, add it to the old iso to create a current iso. I think it's a cool tool though I don't know why the patch between 4.1 and 4.2rc is a little over 38mb.
Guess my point is that it never hurts to experiment and see what can be done. DSL wouldn't even have to support something like this. It's not supported officially in Mepis but the community manages it.
Posted by lucky13 on Dec. 17 2007,21:42
That can't be right. Anyway, I can understand it with dial up and/or something like Mepis -- you're filling up a full CD or DVD, so it's at least 700MB with each download. With 50MB, it should be much less of an issue. Especially if you're talking about 20-25% difference each release in download time (even at dial-up speeds) if that diff is right (can't be!). And if that *is* right, and since you'd have to obtain the first ISO, you're talking about saving net 12% download time on the first patch (88/100MB), 17% net (124/150MB) the second patch, 23% net the third, etc. It would take a lot of new releases to make it worth all the hassle, imo.
Posted by b1ackmai1er on Dec. 21 2007,13:55Yes, this is may not be of any use to anyone but it is fun trying new things.
Diff file for 4.2 to 4.2.1 is 300kb.
So there is huge variation in this process.
Posted by lucky13 on Dec. 21 2007,16:00
I see that, and that's why I'm sticking with the real thing, lol.
Posted by clivesay on Dec. 23 2007,21:03blackmailer,
Would be interesting to apply that patch to the 4.2 iso and then check to see that the md5sum of the modified 4.2 and 4.2.1 match.
Posted by b1ackmai1er on Dec. 24 2007,03:33@clivesay
I didnt do a md5sum, but I did do a binary compare to make sure it regenerated the iso correctly.
Posted by humpty on Dec. 25 2007,10:06just a thought, if the kernel hasn't changed, i wonder if you can just diff the knoppix image ?
(not much use for iso users, but for frugal, it might).
Posted by ^thehatsrule^ on Dec. 31 2007,01:06
Yes, you can do that as well (it's generic)