Mailinglist Archive: zypp-devel (116 mails)
| < Previous | Next > |
Re: [zypp-devel] Source refresh policy
- From: Jiri Srain <jsrain@xxxxxxx>
- Date: Thu, 21 Jun 2007 10:59:31 +0200
- Message-id: <200706211059.36219.jsrain@xxxxxxx>
Dne středa 20 červen 2007 22:34 Duncan Mac-Vicar napsal(a):
> On Wednesday 20 June 2007 17:56, Jiri Srain wrote:
> > Hi!
> >
> > This is my suggestion on how to define the refresh policy with refactored
> > ZYPP:
> >
> > We need to keep the information when last a source was refreshed in order
> > to decide whether a source needs to be refreshed or not. In addition, we
> > will need some policies defining whether a source should be refreshed or
> > not.
>
> RepoManager has a RepoStatus query with timestamp and checksum both for
> metadata and last cache build. I think I made them private.
>
> > 2. Tools which should install a package. They should work as fast as
> > possible. we can pay the price of installing package which already has an
> > update at least in some cases.
>
> This assumption is false in most cases. If the metadata is old then what
> will happen is that you will solve a old package that will probably match
> (because packages usually doesnt change dependencies often), but the link
> (filename) will be wrong and the package will fail.
It will depend on the particular situation. When you use factory, you may
refresh the metadata and one minute later when you download a package the
metadata is outdated.
OTOH in enterprise environment, newer package versions are more rare and it
can work as I suggested.
> This exposes a failure in metadata design, only updating the filenames will
> be a quite option for the use case you mention.
>
> Your usecase works if the repo keeps the old version of the package as well
> (or more).
That's why explicitly said that both policies can be configured to the same
value :-)
--
Regards,
Jiri Srain
YaST Team Leader
---------------------------------------------------------------------
SUSE LINUX, s.r.o. e-mail: jsrain@xxxxxxx
Lihovarska 1060/12 tel: +420 284 028 959
190 00 Praha 9 fax: +420 284 028 951
Czech Republic http://www.suse.cz
> On Wednesday 20 June 2007 17:56, Jiri Srain wrote:
> > Hi!
> >
> > This is my suggestion on how to define the refresh policy with refactored
> > ZYPP:
> >
> > We need to keep the information when last a source was refreshed in order
> > to decide whether a source needs to be refreshed or not. In addition, we
> > will need some policies defining whether a source should be refreshed or
> > not.
>
> RepoManager has a RepoStatus query with timestamp and checksum both for
> metadata and last cache build. I think I made them private.
>
> > 2. Tools which should install a package. They should work as fast as
> > possible. we can pay the price of installing package which already has an
> > update at least in some cases.
>
> This assumption is false in most cases. If the metadata is old then what
> will happen is that you will solve a old package that will probably match
> (because packages usually doesnt change dependencies often), but the link
> (filename) will be wrong and the package will fail.
It will depend on the particular situation. When you use factory, you may
refresh the metadata and one minute later when you download a package the
metadata is outdated.
OTOH in enterprise environment, newer package versions are more rare and it
can work as I suggested.
> This exposes a failure in metadata design, only updating the filenames will
> be a quite option for the use case you mention.
>
> Your usecase works if the repo keeps the old version of the package as well
> (or more).
That's why explicitly said that both policies can be configured to the same
value :-)
--
Regards,
Jiri Srain
YaST Team Leader
---------------------------------------------------------------------
SUSE LINUX, s.r.o. e-mail: jsrain@xxxxxxx
Lihovarska 1060/12 tel: +420 284 028 959
190 00 Praha 9 fax: +420 284 028 951
Czech Republic http://www.suse.cz
| < Previous | Next > |