Clustering Search taking 4sec for 100 results

[Allahbaksh Asadullah]

Hi,
I am using Solr for clustering. I am have set number of row as 100 and I am
using clustering handler. The problem is that I am getting the search time
for clustering search roughly 4sec. I have set -Xmx1024m. What is the best
way to reduce the time.
Regards,
allahbaksh