sqlldr的問題

[oracle@qht108 sqlldr]$ cat para.txt
userid=l5m/l5m
control='/home/oracle/sqlldr/control.txt'
data='/home/oracle/sqlldr/data.txt'
log='/home/oracle/sqlldr/log.txt'
bad='/home/oracle/sqlldr/bad.txt'
rows=300


[oracle@qht108 sqlldr]$ sqlldr parfile=para.txt

SQL*Loader: Release 10.2.0.4.0 - Production on Thu Jul 17 13:48:52 2008

Copyright (c) 1982, 2007, Oracle.  All rights reserved.

Commit point reached - logical record count 20
Commit point reached - logical record count 40
Commit point reached - logical record count 60
Commit point reached - logical record count 80
Commit point reached - logical record count 100
Commit point reached - logical record count 120
Commit point reached - logical record count 140
Commit point reached - logical record count 160
Commit point reached - logical record count 180
...

明明指定了rows=300,為何沒有生效?

log.txt如下:
SQL*Loader: Release 10.2.0.4.0 - Production on Thu Jul 17 13:51:24 2008

Copyright (c) 1982, 2007, Oracle.  All rights reserved.

Control File:   /home/oracle/sqlldr/control.txt
Data File:      /home/oracle/sqlldr/data.txt
  Bad File:     /home/oracle/sqlldr/bad.txt
  Discard File:  none specified

(Allow all discards)

Number to load: ALL
Number to skip: 0
Errors allowed: 50
Bind array:     300 rows, maximum of 256000 bytes
Continuation:    none specified
Path used:      Conventional

Table LOAD_01, loaded from every logical record.
Insert option in effect for this table: APPEND
TRAILING NULLCOLS option in effect

   Column Name                  Position   Len  Term Encl Datatype
------------------------------ ---------- ----- ---- ---- ---------------------
U_ID                                                      RECNUM
OWNER                               FIRST     *   ,       CHARACTER
TABLE_NAME                           NEXT     *   ,       CHARACTER
TABLESPACE_NAME                      NEXT     *   ,       CHARACTER
CLUSTER_NAME                         NEXT     *   ,       CHARACTER
IOT_NAME                             NEXT     *   ,       CHARACTER
STATUS                               NEXT     *   ,       CHARACTER
...
DEPENDENCIES                         NEXT     *   ,       CHARACTER
COMPRESSION                          NEXT     *   ,       CHARACTER
DROPPED                              NEXT     *   ,       CHARACTER

value used for ROWS parameter changed from 300 to 20
....

為何把300自動改成20了呢