Query for times

Hi,

i would like to count how many uris that have response times greater than the 90th percentile times for response times greater than x secs..Say 30 secs and list them out.

I tried this. But it is not resulting any results sourcetype="access_combined_wcookie" host=xxxx Time>30 | eventstats perc90(Time) as hightimes by uri_path | where Time>highimes | table uri_path, count, hightimes