XnView Software

I am a new user. I have many pentax .pef and .jpg files. The Thumbnails seem to be the same size if I choose lossless or lossy low quality jpg
always about 60kb per jpg.
why is this?
it's quite big, my cache is 2gb now, how can I make it smaller?

marcoswat wrote: why is this?
it's quite big, my cache is 2gb now, how can I make it smaller?

Please could you post a sample? But i think that the problem is with makernote data