What sort of %packages section do you have?

Created attachment 157030 [details]
ks used to install machines

The problem here is the size of your %packages section.  We're using a pretty
inefficient group of functions to process each individual package line.  It just
doesn't turn up in most cases because people typically have a small group of
packages listed.  Some work is going in this area, but no real answers yet.

I create a group "mycompanygroup", in comps.xml, with all the packages i use in KS.
Then recreate index with createrepo -g Fedora/base/comps.xml . in the os server.
Then remove all packages in KS, and insert
@mycompanygroup
It's better, but sometimes still consumes 100% of cpu for machine with 256mb.

Can you try a rawhide tree with yum-3.2.2 or later and see if this works better
for you?  Some work has gone into yum to speed this code path up.

for fc6 ? yes. 
Need update aditional package in the tree ?
can i use this ->
http://download.fedora.redhat.com/pub/fedora/linux/development/i386/os/Fedora/yum-3.2.2-2.fc8.noarch.rpm

No, you can't.  You'll need to try an installation from the development tree (or
F8 test 1, which is coming right up).  We don't make anaconda updates for past
releases so testing the development tree is really the only way to check out
these fixes.

humm... ok, but i can't do this now. i have to take another machine, to create
this tree, and then update the repo.
i believe i can do this in september.
thanks.

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