I think 4.9 Gb is the memory u allocated to the Guest mechines in VMware. But, actual memory usage depends on the applications running on all the Guest mechines in VMware ( i.e showing less than 1.2 Gb in host OS Task Manager ).
U can also check this actual memory usage by opening Task Manager in Guest mechines.
Pls go through the <a href=”http://www.vmware.com/support/ws3/doc/ws32_performance3.html”> Memory Usage on VMware Workstations </a>.
I hope this will work for u.
If you have more concerns pls let us know.
Thanks & Regards,