[Yum] Yum speedup

[seth vidal]

On Wed, 2006-03-29 at 09:33 -0500, Brian Long wrote:
> >
> >
> >Personally, I'd propose a different approach. While up-to-date
> >versions do really matter when I am fetching security updates, they
> >are typically less important when doing an "install". It could be
> >configurable, how frequently yum updates its cached lists, depending
> >on the operation. For example, I could configure "every time" for
> >"update", and "two weeks" for "install".
> >  
> >
> This exists in some form in yum-2.4.2.  The metadata is cached by 
> default for 2 hours, I believe.  I just got bitten by this last night 
> while doing upgrade testing.  We integrate yum into our RHEL 3 / 4 
> releases for internally-controlled updates.  Part of our yum-config RPMs 
> point to versioned repositories.  For example, we have a version of 
> Cisco Enterprise Linux based on RHEL 3 Update 5 and another upcoming one 
> based on Update 7.  We have yum-config RPMs which point to different 
> baseurl's depending on the release, but the repository names are the same.
> 
> While testing our update wrapper (which points you from one versioned 
> release to the next), I found the metadata for the old version was being 
> cached.  When I tried a "yum groupinstall", it was trying to used cached 
> metadata for the RPMs contained in the group and those RPMs didn't exist 
> because they had been updated out from under the cached data.  :)
> 

it's metadata_expire =

it's set to 1800 seconds (30 minutes) by default and it is settable
per-repo so you can set it to a low number on repos that frequently
update and high numbers on repos that do not.

-sv