Request shown in slow logs
The option log_queries_not_using_indexes is probably the cause.

From the MySQL Server Option


  If you are using this option with the slow query log enabled, queries
  that are expected to retrieve all rows are logged. See Section 5.2.5,
  “The Slow Query Log”. This option does not necessarily mean that no
  index is used. For example, a query that uses a full index scan uses
  an index but would be logged because the index would not limit the
  number of rows.


So, your query is a "not using index query" and a "full scan query"...

mysql&gt; explain select * from yourTable LIMIT 10 OFFSET 100\G
*************************** 1. row ***************************                                                                                                                                                                            
           id: 1                                                                                                                                                                                                                          
  select_type: SIMPLE                                                                                                                                                                                                                     
        table: yourTable
         type: ALL
possible_keys: NULL
          key: NULL
      key_len: NULL
          ref: NULL
         rows: 124386
        Extra: 
1 row in set (0.01 sec)