ERROR: heapgettup: failed ReadBuffer

I put  360000+ rows in a table , and now any select , update , analyze 
... command fail.
the log shows  "ERROR: heapgettup: failed ReadBuffer",
but any INSERT sql command success.


the table schema is
      row        |              type               |     modifiers
---------------+-----------------------------+----------test_id       | integer                     | not nullsnapshot
   | timestamp without time zone |ip_client     | inet                        |ip_server     | inet
  |conn_time     | integer                     |response_time | integer                     |response_head | character
varying          |
 
Check constraints:   "invalid_conn_time" CHECK (conn_time >= 0)   "invalid_resp_time" CHECK (response_time >= 0)


I didn't create any index,
any one know why or suggestion to save the un-readable database?

or anything I mis-configuration ??

Thanks for your help.

June-Yen