pass1 - making usageList (24 chroms): 232 millis pass2 - checking and writing primary data (1353346 records, 3 fields): 1326 millis pass1 - making usageList (24 chroms): 85 millis pass2 - checking and writing primary data (595828 records, 3 fields): 558 millis pass1 - making usageList (24 chroms): 29 millis pass2 - checking and writing primary data (211929 records, 3 fields): 212 millis pass1 - making usageList (24 chroms): 15 millis pass2 - checking and writing primary data (107807 records, 3 fields): 114 millis