virtual machine implementation can be software. at the base we are sharing same hardware resources.
Virutal machine software (virtual machine implementation ) run in kernel mode
virtual machine itself (vm1~3) runs in user mode.
Inside virutual machine they have their own User mode and Kernel Mode but they run in a physical User mode(main)
for each virutal machine there will be particular area inside hardware will be assigned. Each VM is isolated from each other.
SYSGEN used to configure or generate for each specific computer site. what is determined by SYSGEN?
- what CPU is to be used?
- How much memory is available?
- What devices are available?
- What operating-system options are desired?
System boot = procedure of starting a computer by loading the kernel is know as booting the system.
bootstrap loader = located teh kerenl into memory because hardware it self dosen't know how.
it is in ROM because it needs no initialization and cannot be infected by computer virus.
Firmware = is kind of ROM for mobile device , OS and Bootstrap Loader lies in here
EPROM(Erasble Programable Read Only Memory) , it can be also writable.
after bootstrap loads kernel into memory and starts its exectuion , at this point we can say that system is "RUNNING"
Process = program in execution
thread = unit of execution in process