why doesn't yum cache anything?

[Farkas Levente]

Konstantin Ryabitsev wrote:
> On Fri, 31 Dec 2004 11:51:33 -0500, seth vidal <skvidal at phy.duke.edu> wrote:
> 
>>are you using mirrorlists or are you using baseurls?
> 
> 
> There is a rather annoying side-effect of mirrorlists -- mirrors may
> not always be in sync, so quite often I issue "yum list updates" and
> see that there are updates, but when I run "yum update" it hits a
> different mirror, where these updates are not yet available. As a
> side-effect, it has to download and parse primary.xml.gz for updates
> each time the mirrors are not in sync, which depending on the
> connection and processor can take a significant amount of time. I get
> around it by forcing -C (cache-only mode) after initially running yum
> to get the repomd.xml, but others may not know about it.
> 
> I don't have any solutions to propose, unfortunately, other than
> mirroring an admittedly confusing behavior of apt, which requires
> specifically issuing "apt update" to get new repository medatada.
> 
> However, especially in the cases where domain resolution takes forever
> (some ISPs, in a vain attempt to combat spamming from zombie clients,
> throttle down DNS responses to take 10-15 seconds), non-cache
> operations with mirrorlists take quite some time more than -C.

just try out a:
time yum -C list mtr
it has nothing to do with the network and the speed is almost the same!
it seems there are two place where yum is very slow:
- loading the local metadata (even if using the pickle files)
- the dependencie resolution
probably it needs to investigate further what is the real reason and how 
can be solve. if yum be so slow for a long time, there will be someone 
who create another package using a better/more clever local cache file 
format and and may be reimplement it in a faster language (may be a 
better/faster server side metadata format). and even if it has less 
features more people will use it. currently everyone use yum since most 
people hate up2date and apt's (rpm -U --force) feature is not sounds 
good. but that won't take forever...


-- 
   Levente                               "Si vis pacem para bellum!"