Presto: Speed up your updates and save bandwidth

[BlownCPU]

thanks for the info

[mpajoh]

Is there always a presto package available when full packages are available?
If not what is the lag time between the two?

[sideways]

Originally Posted by marko

But some rpm's include config files that you have to edit, then how does
presto work around your changes? If the original rpm isn't necessarily retained
and presto is using the actual on disk copy that you've edited for your
personal configuration, I'm not sure I understand how it could handle that?
Anyway, I guess it works somehow and that's what matters to me.

Mark

The rpm maintainer can specify files to never overwrite using .rpmnew and .rpmsave extensions
http://www.linux.com/feature/121476


This is a good development, and about time (I might actually update openoffice in future). Now if they can just make the metadata a delta too (duh)

[Firewing1]

Originally Posted by marko

But some rpm's include config files that you have to edit, then how does
presto work around your changes? If the original rpm isn't necessarily retained
and presto is using the actual on disk copy that you've edited for your
personal configuration, I'm not sure I understand how it could handle that?
Anyway, I guess it works somehow and that's what matters to me.

Mark

RPM keeps track of which configuration files shouldn't be touched - These are the 'rpmnew' and 'rpmsave' files that Sideways spoke of. I'm guessing in the case of those files, the updated configuration file is included and then deltarpm decides if it should save your configuration before applying it or if it should leave the configuration in place and append .rpmnew to the filename for example.

Originally Posted by mpajoh

Is there always a presto package available when full packages are available?
If not what is the lag time between the two?

It depends on the deltarpm repository maintainer, but in this case yes. The repository sync every hour iirc and the server needs a bit of time to build the delta packages so I'd imagine the difference is no more than three hours. But if a deltarpm isn't found it falls back to the full package, so you don't have to worry about 404 errors.

Firewing1

[sideways]

Has anyone tested the difference when doing an update on a clean install? I tried it from a livecd session but both methods indicated a 313Mb download.

[bmvbab]

sideways....they both show only the total package size based on the rpm packages and not the drpms...dont know why this has not been implemented or working, but the actual download time and size would be very less than what is shown.

[koperry]

It does speed up a fresh install. I went in on a fresh install and ran rm /var/run/yum.pid, yes and then installed yumex, then went in and installed fastest mirror and presto along with any other yum options you may want then ran yum update from the cli and it seemed to be a much quicker initial update on the fresh install.

[havenoclu]

Wow, this is great. Thanks!

[sideways]

Originally Posted by bmvbab

sideways....they both show only the total package size based on the rpm packages and not the drpms...dont know why this has not been implemented or working, but the actual download time and size would be very less than what is shown.

But has anyone actually confirmed this? ie with real measured stats, not just "guesswork".

From what I read, unless the installed rpms come from a deltarpm enabled repo originally then yum-presto won't make any difference, and I don't think the install disk repos are deltarpm enabled.

Perhaps in F9.

So, yum-presto only works well once you have done a few large updates with it, after a clean install it makes no difference.

I think.

[adrianx]

Originally Posted by sideways

But has anyone actually confirmed this? ie with real measured stats, not just "guesswork".

From what I read, unless the installed rpms come from a deltarpm enabled repo originally then yum-presto won't make any difference, and I don't think the install disk repos are deltarpm enabled.

Perhaps in F9.

So, yum-presto only works well once you have done a few large updates with it, after a clean install it makes no difference.

I think.

Hi Sideways,

Even though I have not done a fresh install, I can tell you that tonight (8:00pm GMT+2) I did an update. The total update was approx. 72MB. I installed presto about 2 days ago, so none of my packages were drpm's. I was expecting to see a 50% reduction in bandwith, but it was actually a whole lot more! It is almost as if ( by some miracle ) "it reads" the packages you have installed, then it does a diff and re-packages whatever you have installed.

In other words - it converts drpm into rpm and does a normal yum update. Check it out. You won't be disappointed.

[sideways]

Originally Posted by adrianx

Hi Sideways,

Even though I have not done a fresh install, I can tell you that tonight (8:00pm GMT+2) I did an update. The total update was approx. 72MB. I installed presto about 2 days ago, so none of my packages were drpm's. I was expecting to see a 50% reduction in bandwith, but it was actually a whole lot more! It is almost as if ( by some miracle ) "it reads" the packages you have installed, then it does a diff and re-packages whatever you have installed.

In other words - it converts drpm into rpm and does a normal yum update. Check it out. You won't be disappointed.

Well if that's the case, it really is great! One of the true annoyances of starting up a fresh fedora install is the several hundred megabytes of automatic updates applied (Especially if openoffice has an update)

[Firewing1]

I've tested the reported download size since it used to show the DRPM size... I'm not sure why it switched, but the reported size shows the "normal" size, once you start downloading the drpms you'll find the actual download is much less.

As for the fresh install, Jonathan (the presto repo maintainer) keeps his drpms until the release hits EOL - So even if you have a fresh install you'll benefit from the bandwidth savings.
Firewing1

[leadgolem]

Due to my own stupidity I recently had to reinstall fedora 8. I just did the system update with presto all setup. I had to download 188 full packages, and 95 drpms. The whole update process took about 35 minutes, and was supposed to include the 476 megs of updates. My connection isn't great, and there is no way I got 476mb in 35 minutes.

[sideways]

yum-presto is quite obviously the greatest addition to fedora in its (short) history.

However, it's also a f**king obvious way to manage updates, and the fact it hasn't been done this way before is shockingly embarrassing.

I have posted in the past that the metadata should surely be a diff, you don't want a 10mb download of metadata when you're just asking yum to install a 35kb telnet server for example.

kudos to the deltarpm engineers, but it was a long time coming, and an obvious common-sense solution.

[marko]

Did any other distribution go with delta packages before Fedora? Just wondering...