i am working on parallel graphics i m displaying one image on 4 different clients but the image is not displayed at same time some tile is displyed image earlier and some takes time

i am using mpich for message passing so is there any way to synchronize these events so that all images will be displyed simultaneously

i am using linux redhat 9 smp
QT3 and openGL for image division and dislay
mpich1.2.7

so plz help me