Specifications

Administration Guide
74 VMware, Inc.
Recommended Configuration Options
This!section!details!options!that!can!influence!the!performance!of!your!virtual!
machines.!These!settings!are!not!required!to!run!VMware!ESX!Server!correctly.!
SleepWhenIdle
The!configuration!file!option!monitor.SleepWhenIdle!determines!whether!the!
VMkernel!deschedules!an!idle!virtual!machine.!By!default,!this!option!is!enabled,!a!
setting!that!ensures!much!better!performance!when!running!multiple!virtual!machines.!
When!you!are!running!only!a!single!virtual!machine!(such!as!for!benchmarking!
VMware!ESX!Server),!add!the!monitor.SleepWhenIdle
!option!to!the!virtual!
machine’s!configuration!file!if!you!want!to!achieve!the!best!possible!performance!in!the!
virtual!machine!(at!the!expense!of!responsiveness!in!the!service!console).!
Create!an!option!called!monitor.SleepWhenIdle!and!set!the!value!of!this!option!to!0,!
as!described!in!“Setting!Startup!and!Shutdown
!Options!by!Modifying!the!
Configuration!File!Directly!(Advanced!Users!Only)”!on!page 126.
Optimizing Disk Access Failure Modes in Windows Virtual Machines
ESX!Server!includes!configuration!options!that!allow!you!to!optimize!how!virtual!
machines!handle!disk!access!failures.!For!Windows!virtual!machines,!use!the!
scsi<n>.returnBusyOnNoConnectStatus!option!to!determine!how!ESX!Server!
reports!a!failure!to!connect!with!a!virtual!SCSI!adapter!or!failure!to!access!it!after!
initiating!a!connection.!By!setting
!the!option!to!TRUE!or!FALSE,!you!can!determine!how!
the!failure!to!access!to!a!physical!disk!is!represented!to!your!Windows!virtual!machine.
The!values!are!described!below:
! If!the!option!is!set!to!TRUE, !ESX!Server!returns!the!error!message!SCSI BUSY.
! If!the!option!is!set!to!FALSE, !the!value!ESX!Server!returns!depends!on!the!type!of!
SCSI!controller!you!chose!for!that!virtual!device:
! If!you!chose!the!BusLogic!adapter!(that!is,!if!Virtual!Device!is!set!to!
vmxbuslogic),!your!virtual!machine!receives!the!error!message!
DEVICE_NOT_THERE.
! If!you!chose!the!LSI!Logic!adapter!(that!is,!if!Virtual!Device!is!set!to!
vmxlsilogic),!your!virtual!machine!receives!the!error!message!
BTSTAT_SELTIME0.
You!might!need!to!set!returnBusyOnNoConnectStatus!to!FALSE!when!disk!
management!software!operating!in!a!Windows!virtual!machine!needs!to!detect!access!
failures.!For!example,!some!
types!of!disk!mirroring!software!will!not!select!a!duplicate!
disk!unless!they!detect!a!discrete!failure!to!access!a!primary!disk.!Reporting!that!a!