yum slow on Fedora 10 after last update

With our repo configuration, yum has become much slower on Fedora 10
since the last upgrade. With yum-3.2.23-3.fc10 check-update takes ~ 25
times longer than with yum-3.2.21-2.fc10 (3 minutes cf 7 seconds).

It's because we have a local updates repo and a remote one with (mostly)
the same content.  If I disable either of those check-update takes a few
seconds - with both enabled it now takes 3 minutes.

Running with '-e10 -d10' shows it spends most of it's time outputting
lines like:

   excluding for cost: _package_ from updates-debuginfo

The reason for two repos is that the local one lags behind so sometimes
there are additional updates available from the remote.  (The local has
cost=100 to ensure updates come from there preferentially).

Is this type of configuration no longer viable?


Thanks
-- 
Ian