An MSJET database layer can be slow and consume a lot of memory if there is a lot of records. For better performance in such case, add to your .TTKLS file ENGINEOPTIONS=8, like in this example:

  [TatukGIS Layer]
  Storage=Native
  LAYER=lwaters
  DIALECT=MSJET
  ADO=Provider=Microsoft.Jet.OLEDB.4.0;Data Source=gistest.mdb
  ENGINEOPTIONS=8

This will force server side cursor instead of client side cursor.