(How to) repair/optimize large Post table (1Gb), hang using admincp/phpmyadmin

[basketmen]

i can repaired and optimized all tables from admincp -> Maintanance with no problem, except the Post table, because its already have large size (1Gb)

so i try repair that single table alone :

try it from admincp -> Maintanance, Its stopped loading by its self in the middle only get Please wait..., no Done message at all, its just hanged

try it from phpmyadmin, get very high load in the middle, cannot opening the server or the whm/cpanel even already more than 30 minutes, so need to restart the server from leap (manual reboot by the host company)

so is there any way to repair and optimize it guys? or it is no need to repair/optimize for years?

Nb. I use a dedicated server, here is my server specs
Intel Single Xeon E3110 3.0ghz L2 cache 6MB
Memory 4 GB DDR2 RAM
Harddisk 500 GB Sata 7200rpm
Cent OS 5.4
WHM/Cpanel

vb 3.6