Specifications

VMware, Inc. 367
Chapter 12 VMware ESX Server Resource Management
If!memory!sharing!achieves!a!10!percent!savings!(410MB),!the!total!memory!overhead!
drops!to!only!510MB.!If!memory!sharing!achieves!a!25!percent!savings!(1GB),!the!
virtualized!workload!actually!consumes!104MB!less!memory!than!it!would!on!eight!
physical!servers.
It!may!also!make!sense!to!overcommit!memory.!For!example,!
suppose!that!on!average,!
two!of!the!eight!Web!server!virtual!machines!are!typically!idle!and!that!each!Web!server!
virtual!machine!requires!only!256MB!to!provide!minimally!acceptable!service.!In!this!
case,!the!hardware!memory!size!can!be!reduced!safely!by!an!additional!2!*!256MB!=!
512MB.!In!the
!worst!case!where!all!virtual!machines!are!active!at!the!same!time,!the!
system!might!need!to!swap!some!virtual!machine!memory!to!disk.
For!additional!background!information!on!ESX!Server!memory!usage,!see!“Memory!
Resource!Management”!on!page 345.
Managing Network Bandwidth
VMware!ESX!Server!supports!network!traffic!shaping!with!the!nfshaper!loadable!
module.!A!loadable!packet!filter!module!defines!a!filter!class;!multiple!filter!instances!
may!be!active!for!each!loaded!class.!The!current!release!supports!only!one!filter!class,!
nfshaper,!which!is!a!transmit!filter!for!outbound!bandwidth!management!that!
can!be!
attached!to!virtual!machines!using!either!a!procfs!interface!on!the!service!console!or!
the!VMware!Management!Interface.!
Using Network Filters
This!section!describes!how!to!use!the!VMware!Management!Interface!to!attach!and!
detach!nfshaper!and!obtain!statistics!from!it.!It!also!describes!how!to!attach,!detach,!
and!query!filter!instances!from!the!procfs!interface!on!the!service!console.!
Managing Network Bandwidth from the Management Interface
You!can!view!and!change!settings!from!the!virtual!machine!details!pages!in!the!
VMware!Management!Interface.!
To change settings from the VMware Management Interface
1On!the!server’s!Status!Monitor!pane,!click!the!name!of!an!individual!virtual!
machine.
The!details!page!for!that!virtual!machine!appears.!