thanks George, I will try it soon.
by the way using LSWS 4.2 -suEXEC daemon- new feature makes php login session suddenly throw out.
I have got two complaints regarding to this.
and as my 1st post, it using swap much even phisycal RAM space have enough space.
I don't know what I am missing, but my two boxes bring the same behaviour about login session and force using swap.