There is no performace graph

There is no performance graph in my vSphere client for a specific host.

I checked the DB and saw that the "last_perf_time"  field in the "vpx_host" table did not changed for 3 days for that host.

I updated this entry using a sql command : "update vpx_host set last_perf_time = getutcdate();" based on this solution : kb.vmware.com/kb/1018256

but it didn't work and the problem still ramining after 2 days.

The "last_perf_time"  field for other hosts changes and the performance graphs are okay,

Any idea?