Ask Fedora
In this section, we answer general questions from Fedora community. Send your questions to askfedora AT fedoraproject.org and Fedora News Team will bring you answers from the Fedora Developers and Contributors to selected number of questions every week as part of our weekly news report. Please indicate if you do not wish your name and/or email address to be published.
http://fedoraproject.org/wiki/AskFedora
Ext4 Filesystem on Solid State Disks
A question on Ext4, that has already been made the default in the development tree headed for Fedora 11 was answered by Eric Sandeen, Red Hat ext4 and XFS filesytems developer.
Contributing Writer: Eric Sandeen
Francesco Frassinelli wrote: "I've read that in F11 ext4 will be the default filesystem. What about ext4 on solid state disk? Many websites and bloggers say that it's better to use ext2 because of the journaling, but in some kind of operation (like applying upgrades) it's sooo slow. Could we'll use ext4 on our ssd without compromising their life? TBH I haven't tested ext4 on ssd yet, though we do have some in the lab, I just haven't done it."
Eric Sandeen replied: "By default ext4 still journals pretty much the same as ext3 does, so if you want to minimize writes to your flash, it should not be significantly better than ext3 in that respect. However, there is a patch to ext4 (merged soon if not already) to allow it to run in a no-journal mode, so that may be a good option.
-Eric
Thorsten Leemhuis added: "FYI, it was merged[1] for 2.6.29"
Contributing Writer: Matt Domsch
Local Fedora Repository Management Best Practices?
Erik Turk <erikt@bbn.ca>
Hello to Ask Fedora Team. I am just starting to maintain my own Fedora 8 repositories for my local use. I think that these questions are about best practices for maintaining a Fedora repository. I have found many articles about how to create your own fedora repository
1. How can I determine the intersection of the i386 and x86_64 repositories, both for updates and base?
I have noticed that there are several ( I don't know how many ) packages that exist in both the i386 and the x86_64 arch folders. These are i386 packages that exist in the x86_64 updates folder such as:
adminutil-1.1.5-1.fc8.i386.rpm adminutil-1.1.5-1.fc8.x86_64.rpm
Also, there are noarch packages which appear in both i386 and x86_64 repositories.
Is there any way that I can download the .i386 package once and have it linked (to save local disk space as well as the download bandwidth) to the x86_64 directory for packages that appear in both?
What are the implications of downloading the updates first for i386, then copying all the i386 update packages to the x86_64 update folder, then rsync'ing the x86_64 update folder? Will this download only the x86_64 packages
How can this work with the rsync command that many of the "create your own repository" articles use? I recognize that this is only important for people who maintain both repositories locally.
2. (5 of the top 20 update packages by size, as of April 16,2008 ) and (12 of the top 20 base packages by size in the Everything Folder) are games.
In the Everything base folder, these 12 packages are over 1GB of data, close to 10% of the total of the directory.
Is there any way to identify these as a group in the repository so that they are not downloaded as part of an rsync run, other than excluding them individually?
3. With the upcoming release of Fedora 9, How can I save bandwidth by "converting" my Fedora 8 repositories into Fedora 9 repositories, without re-downloading the entire Everything folder? Is there a process that can be followed by local repositories at each new Fedora release?
I know that many packages will have new fc9 files, but some will still be fc8 in the f9 repo. How can I determine which ones to copy vs which ones to download?
---
Matt Domsch answers:
> > Hello to Ask Fedora Team. I am just starting to maintain my own Fedora 8
> > repositories for my local use. I think that these questions are about best
> > practices for maintaining a Fedora repository. I have found many articles
> > about how to create your own fedora repository
Most of these articles are outdated. Instead, see http://fedoraproject.org/wiki/Infrastructure/Mirroring.
> > 1. How can I determine the intersection of the i386 and x86_64
> > repositories, both for updates and base?
> >
> > I have noticed that there are several ( I don't know how many ) packages
> > that exist in both the i386 and the x86_64 arch folders.
> > These are i386 packages that exist in the x86_64 updates folder such as:
> >
> > adminutil-1.1.5-1.fc8.i386.rpm
> > adminutil-1.1.5-1.fc8.x86_64.rpm
> >
> > Also, there are noarch packages which appear in both i386 and x86_64
> > repositories.
> >
> > Is there any way that I can download the .i386 package once and have it
> > linked (to save local disk space as well as the download bandwidth) to the
> > x86_64 directory for packages that appear in both?
Yes, rsync -H (as described at the above URL) will preserve hardlinks, and these files are hardlinked on the mirrors.
> > What are the implications of downloading the updates first for i386, then
> > copying all the i386 update packages to the x86_64 update folder, then
> > rsync'ing the x86_64 update folder? Will this download only the x86_64
> > packages
Just use rsync -H and this will happen automagically.
> > How can this work with the rsync command that many of the "create your own > > repository" articles use? I recognize that this is only important for > > people who maintain both repositories locally. > > > > 2. (5 of the top 20 update packages by size, as of April 16,2008 ) and (12 > > of the top 20 base packages by size in the Everything Folder) are games. > > > > In the Everything base folder, these 12 packages are over 1GB of data, > > close to 10% of the total of the directory. > > > > Is there any way to identify these as a group in the repository so that > > they are not downloaded as part of an rsync run, other than excluding them > > individually?
No.
> > 3. With the upcoming release of Fedora 9, How can I save bandwidth by > > "converting" my Fedora 8 repositories into Fedora 9 repositories, without > > re-downloading the entire Everything folder? Is there a process that can > > be followed by local repositories at each new Fedora release? > > > > I know that many packages will have new fc9 files, but some will still be > > fc8 in the f9 repo. How can I determine which ones to copy vs which ones > > to download?
There are very few, and again, the whole tree on the mirrors is hardlinked, so any packages that haven't been updated won't be downloaded again, just hardlinked.
Thanks,
Matt
Fedora Mirror Wrangler