how to calculate the number of M9k that nios onchip memory occupied?

hi, thanks for replying.

i check the fitter report:

http://www.alteraforum.com/forum/attachment.php?attachmentid=11266&stc=1

i also think that may be my problem, but the fitter report shows that the 163840 bit occupy 32M9ks

by the way, when i change the on chip memory size from 20480 bytes to 16384 bytes, the fitter report told me it takes only 16 M9ks

can you give me more advise? thanks!