[CentOS-mirror] Proposel - jigdo for iso Images

Fri Oct 30 08:22:48 UTC 2009
J.H. <warthog9 at kernel.org>

Billy Vierra wrote:
> On Oct 29, 2009, at 10:52 PM, "J.H." <warthog9 at kernel.org> wrote:
>> Uwe Kiewel wrote:
>>> Tru Huynh schrieb:
>>>> On Thu, Oct 29, 2009 at 02:59:22PM -0400, Nick Olsen wrote:
>>>>> Addition of jigdo yes. Replace ISO's no.
>>>>> Educating joe sixpack on using something new, well I like to use
>>>>> altercation avoidance.
>>>> please no top posting ;)
>>>> There was a thread about jidgo in the archives and it boiled down
>>>> to:
>>>> - someone has to maintain the jidgo package in the CentOS tree
>>>> (how would a CentOS user for C3/4/5 use jidgo?)
>>>> - document it in the wiki (how to use, at least)
>>>> - someone needs to make it work from the current setup
>>>> - how much burden will it put on the mirrors? centos.org ones and
>>>> public ones?
>>>> (I have no experience on using it)
>>>> - no one volonteered.
>>>> - one more thing to check for the QA release process.
>>>> back to you :)
>>> Ok. Understood.
>>> It was just an idea because Fedora do it successfuly since Fedora 6
>>> and
>>> Debian do so as well.
>> Ok back that monkey truck up slightly here.  Fedora has *ONLY* been
>> doing it for the Fedora Spins stuff which, as you can imagine, an
>> *INCREDIBLY* low volume set of accesses.  Debian is going to be
>> likewise, and I wouldn't exactly call it a popular thing from them.
>> Speaking as a mirror here are my thoughts:
>> - Cutting down on the working data set is a good thing, though I do
>> have
>> some serious reservations about this on a larger scale.
>> - Claiming a webserver doesn't handle large files is a bogus
>> statement,
>> if your on Linux you have send_file() and that is darned fast and
>> efficient.  It more or less doesn't matter what your file size is
>> for that.
>> - If your on a client, or a server, and it doesn't support http
>> restarts
>> you really have to ask why?  I can understand how *PAINFUL* that is
>> to a
>> mirror to do a random seek into the middle of a file, but once the
>> download has started it's effectively no additional overhead beyond
>> that.
>> - Speaking to the apache module that auto-generates the iso on the
>> fly:
>> any mirror of any reasonable size will shoot this down in a heartbeat.
>> We already have an I/O problem on the systems, ram issues, etc.
>> Adding
>> something into apache that's going to thrash about and magically
>> generate this as it's requested is *WORSE* than the wasted disk space.
>> Again send_file() is your friend.
>> My thoughts
>> ------------
>> Honestly if Centos is actively looking to eliminate the ISOs I would
>> tentatively support this, but Jigdo (at least the last time I used it)
>> is *ANYTHING* but userfriendly.  It would *HAVE* to be as simple as
>> download a script, program, etc you get a download box and *poof* your
>> dvd comes out, no user interaction unless a lot of advanced options
>> are
>> selected somewhere, and last time I used it it wasn't that simple.
>> Furthermore I think jigdo is likely going to be a lot of work, with
>> little payoff.  From my gut reaction I think moving to more of a
>> universal network installer (ala http://boot.kernel.org w/ it's
>> network
>> installers, which happen to include Centos)[Disclaimer: I'm one of the
>> devs & the primary admin for http://boot.kernel.org] is a *LOT* more
>> intuitive to a user and a lot simpler to get them to use than Jigdo
>> ever
>> will be, and honestly it gets a user moving sooner and it can take
>> less
>> time anyway depending on what a user selects, has all of the
>> advantages
>> of Jigdo and with significantly fewer downsides.
>> Just my $0.02
>> - John 'Warthog9' Hawley
>> Chief Kernel.org Administrator
>> _______________________________________________
>> CentOS-mirror mailing list
>> CentOS-mirror at centos.org
>> http://lists.centos.org/mailman/listinfo/centos-mirror
> I agree with the apache module not being feasable... On top of the
> fact you have additional resource usage from it you are making a huge
> assumtion that the mirror is running apache.
> As great as apache is, it is resource hog. Something that only serves
> high volume static files is rarely running apache.

I dunno, I run Apache quite successfully and I would argue I'm a high 
volume content provider.

- John 'Warthog9' Hawley
Chief Kernel.org Administrator