Thanks Tom Lane, I think we must have to consider about your last mail words. But now reducing the table is mearly impossible, but very thanks for advice , we will try it in future.
> So do i have to increase the max_fsm_relation based on (Average_no_relation > per db * number of db)? if so it will be very high since in our one db > server we have 200 db with average 800 tables in each db. What is the value > we have to give for this kind of server?
About 160000.
One wonders whether you shouldn't rethink your schema design. Large numbers of small tables usually are not a good use of SQL. (I assume they're small, else you'd have had serious bloat problems already from your undersized max_fsm_pages setting ...)