Specifications

Table Of Contents
VMware, Inc. 223
Chapter 8 Configuring Devices
communicate!over!a!serial!connection.!For!more!information,!see!“Special!
Configuration!Options!for!Advanced!Users”!on!page 223.
10 Click!Finish,!and!click!OK!to!save!your!configuration!and!close!the!virtual!
machine!settings!editor.
11 Repeat!these!steps!for!the!client!virtual!machine.
Special Configuration Options for Advanced Users
Two!special!configuration!options!are!available!for!serial!connections!between!a!virtual!
machine!and!the!host!or!between!two!virtual!machines.!These!options!are!of!interest!
primarily!to!developers!who!are!using!debugging!tools!that!communicate!over!a!serial!
connection.!
Improving Processor Performance When Debugging
The!first!option!must!be!set!in!the!virtual!machine!settings!editor!(VM!>!Settings!>!
Serial!Port).!This!option!is!useful!when!the!serial!port!is!being!used!by!the!guest!
operating!system!in!polled!mode!as!opposed!to!interrupt!mode.!Polled!mode!causes!the!
virtual!machine!to!consume
!a!disproportionate!share!of!processor!time.!This!makes!the!
host!and!other!guests!run!sluggishly.
To!restore!performance!for!applications!on!the!host,!check!the!Yield!CPU!on!poll!check!
box.!This!configuration!option!forces!the!affected!virtual!machine!to!yield!processor!
time!if!the!only!task!it!is!trying!to
!do!is!poll!the!virtual!serial!port.
Changing the Input Speed of the Serial Connection
To!use!the!second!option,!power!off!the!virtual!machine!and!close!the!console!window.!
Use!a!text!editor!to!add!the!following!line!to!your!virtual!machine’s!configuration!file!
(.vmx):
serial<n>.pipe.charTimePercent = <x>