Microsoft SharePoint Foundation Usage Data Import Job Stuck at 0%

Hello,

My Sharepoint portal is really slow. And I have noticed that the timer job Microsoft SharePoint Foundation Usage Data Import is stuck at 0%. I think this problem came after I generated some usage reports in the site collection.

Also when I restart the Sharepoint 2010 Timer service navigation speed in my portal restores to normal, but as soon as the job restarts it gets slow again.

Any ideas how I can solve this issue?

Regards,