The culprit that do large write to my hard disk has been caught.
It's kjournald
One way to solve the issue is to change the file system to ext2. Is there an easy way to do so?
Another thing that can work is to increase commit time to hard disk.
What does it actually do? If I make commit time 600 seconds will my hard disk fail to write for 600 seconds?
Will it mean less journalling or just delayed journalling?
The data are mostly cache and I don't need perfect accuracy.
We don't have journalling for windows right?