[GENERAL] postgresql in ramdisk

[oruc çimen]

hi;
i have tested postgresql in memory  but in ramdisk is not faster than
hardisk.
why??? if there are some option for postgresql in ramdisk, pls help me
i need too much fast db if you know another way for fast db pls send a mail
to me
thank you
(sorry for my bad english:(   )
G.Oruc Cimen