= Proposed System Wide Change: Zchunk Metadata = https://fedoraproject.org/wiki/Changes/Zchunk_Metadata
Owner(s): * Jonathan Dieter <jdieter at gmail dot com> * Neal Gompa <ngompa13 at gmail dot com>
All dnf repository metadata will be compressed with the zchunk format rather than xz or gzip.
== Detailed description == Currently Fedora's repository metadata is compressed using the xz and gzip formats. Zchunk is a new compression format designed to allow for highly efficient deltas. When Fedora's metadata is compressed using zchunk, dnf will download only the differences between any earlier copies of the metadata and the current version.
== Scope == * Proposal owners: ** Package zchunk for Fedora ** Get the pull requests to enable zchunk in dnf, libdnf, librepo, libsolv and createrepo_c merged upstream *** https://github.com/rpm-software-management/librepo/pull/127 *** https://github.com/openSUSE/libsolv/pull/270 *** https://github.com/rpm-software-management/dnf/pull/1107 *** https://github.com/rpm-software-management/libdnf/pull/478 *** https://github.com/rpm-software-management/createrepo_c/pull/92 ** Create a new package for Fedora's zchunk dictionaries.
* Other developers: Fedora Infrastructure needs to start creating zchunked metadata
* Release engineering: #7600 [https://pagure.io/releng/issue/7600]
** List of deliverables: Zchunk repository metadata
* Policies and guidelines: Packaging guidelines are not affected by this change.
* Trademark approval: N/A (not needed for this Change)
On Mon, Jul 2, 2018 at 1:19 AM Jan Kurik jkurik@redhat.com wrote:
= Proposed System Wide Change: Zchunk Metadata = https://fedoraproject.org/wiki/Changes/Zchunk_Metadata
Owner(s):
- Jonathan Dieter <jdieter at gmail dot com>
- Neal Gompa <ngompa13 at gmail dot com>
All dnf repository metadata will be compressed with the zchunk format rather than xz or gzip.
== Detailed description == Currently Fedora's repository metadata is compressed using the xz and gzip formats. Zchunk is a new compression format designed to allow for highly efficient deltas. When Fedora's metadata is compressed using zchunk, dnf will download only the differences between any earlier copies of the metadata and the current version.
How does this work with distribution upgrades? If we only produce zchunk compressed metadata, but dnf in f28 doesn't even understand it, that seems wrong.
josh
On 9.7.2018 23:52, Josh Boyer wrote:
On Mon, Jul 2, 2018 at 1:19 AM Jan Kurik jkurik@redhat.com wrote:
= Proposed System Wide Change: Zchunk Metadata = https://fedoraproject.org/wiki/Changes/Zchunk_Metadata
Owner(s):
- Jonathan Dieter <jdieter at gmail dot com>
- Neal Gompa <ngompa13 at gmail dot com>
All dnf repository metadata will be compressed with the zchunk format rather than xz or gzip.
== Detailed description == Currently Fedora's repository metadata is compressed using the xz and gzip formats. Zchunk is a new compression format designed to allow for highly efficient deltas. When Fedora's metadata is compressed using zchunk, dnf will download only the differences between any earlier copies of the metadata and the current version.
How does this work with distribution upgrades? If we only produce zchunk compressed metadata, but dnf in f28 doesn't even understand it, that seems wrong.
As I understood it form one fo the previous discussions about the topic, zchunk will be only provided together with xz. Older dnf will simply request xz and newer dnf will request zchunk but fallback to xz if it is not available or checksums don't match or whatever error occurs.
On Mon, Jul 9, 2018 at 6:28 PM Miro Hrončok mhroncok@redhat.com wrote:
On 9.7.2018 23:52, Josh Boyer wrote:
On Mon, Jul 2, 2018 at 1:19 AM Jan Kurik jkurik@redhat.com wrote:
= Proposed System Wide Change: Zchunk Metadata = https://fedoraproject.org/wiki/Changes/Zchunk_Metadata
Owner(s):
- Jonathan Dieter <jdieter at gmail dot com>
- Neal Gompa <ngompa13 at gmail dot com>
All dnf repository metadata will be compressed with the zchunk format rather than xz or gzip.
== Detailed description == Currently Fedora's repository metadata is compressed using the xz and gzip formats. Zchunk is a new compression format designed to allow for highly efficient deltas. When Fedora's metadata is compressed using zchunk, dnf will download only the differences between any earlier copies of the metadata and the current version.
How does this work with distribution upgrades? If we only produce zchunk compressed metadata, but dnf in f28 doesn't even understand it, that seems wrong.
As I understood it form one fo the previous discussions about the topic, zchunk will be only provided together with xz. Older dnf will simply request xz and newer dnf will request zchunk but fallback to xz if it is not available or checksums don't match or whatever error occurs.
Can we update the language on the Change page to clarify that?
josh
On Mon, 2018-07-09 at 18:48 -0400, Josh Boyer wrote:
Can we update the language on the Change page to clarify that?
I thought I had explained at: https://fedoraproject.org/wiki/Changes/Zchunk_Metadata#Upgrade.2Fcompat ibility_impact
Is there something I should put that would make it clearer?
Jonathan
On Tue, 2018-07-10 at 08:34 +0100, Jonathan Dieter wrote:
On Mon, 2018-07-09 at 18:48 -0400, Josh Boyer wrote:
Can we update the language on the Change page to clarify that?
I thought I had explained at: https://fedoraproject.org/wiki/Changes/Zchunk_Metadata#Upgrade.2Fcompat ibility_impact
Is there something I should put that would make it clearer?
Ok, I saw your comment on the FESCO ticket, and I see why it's confusing.
I've updated the summary to say: "All dnf repository metadata will be compressed with the zchunk format in addition to xz or gzip."
Jonathan
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Jan Kurik -
Jonathan Dieter -
Josh Boyer -
Miro Hrončok