Horrific time for getting 1 record from an index?

Postgres 9.1.9.

explain analyze select min(insert_time) from cnu_stats.page_hits_raw ;
                                                                               QUERY PLAN

-----------------------------------------------------------------------------------------------------------------------------------------------------------------------
  Result  (cost=0.12..0.13 rows=1 width=0) (actual time=257545.835..257545.836 rows=1 loops=1)
    InitPlan 1 (returns $0)
      ->  Limit  (cost=0.00..0.12 rows=1 width=8) (actual time=257545.828..257545.829 rows=1 loops=1)
            ->  Index Scan using page_hits_raw_pkey on page_hits_raw  (cost=0.00..5445004.65 rows=47165480 width=8)
(actualtime=257545.826..257545.826 rows=1 loops=1) 
                  Index Cond: (insert_time IS NOT NULL)
  Total runtime: 257545.881 ms
(6 rows)


I checked and there were no un-granted locks... but I have a hard time believing it actually too 257 seconds to get 2
pages(one index, one heap) back from our SAN. 

Am I missing something here?
--
Jim Nasby, Lead Data Architect   (512) 569-9461