Transcript Document

Ştefan Stăncescu
PART II
OPERATING SYSTEMS
LECTURE 8
SO TAXONOMY
1
TAXONOMY OS
The operating system
on a real H/W machine
are a compact package of system programs which
manages the H/W
i.e.: CPU, MEM, I/O, EXT MEM
use local H/W system for
running local programs
communicates, stores, processes
(in cloud, for distributed applications)
providing an unified management environment
on different machines
2
SO TAXONOMY
The operating system creates a local VM
efficient
standardized
friendly (or known interface easy to learn)
adaptable to different tasks
VM hide the real machine with
complicate structure
complicate handling
3
SO TAXONOMY
OS classification after resource allocation to processes
- all resources fully allocated only to a process
(batch - batch processing)
- distributed resource allocation multiple processes (PC)
OS classification after response time to the run
- real time RTOS - with guaranteed response time to each
process (processes are important)
- without time constraints - optimal loading of computing
resources (resources are important)
4
SO TAXONOMY
OS classification after process management
single process (dedicated system - embedded)
embedded application is a process hosted by
the unique OS process dedicated to it
cooperative management of processes
running process cooperates in management
preemptive management
OS contains a supervisor which
regulate run or
abort process run
5
SO TAXONOMY
OS classification after executable SO structure
- Compact SO with a single executable file
all resources simultaneously available
- Hierarchical (multilayered) SO with a
module architecture - levels of services provided by
resources => to the user
each level is an abstract stage adaptation
H/W resource <=> system software levels <=> the user
1.
2.
3.
4.
The operator (user) and user processes
Operator-process communication and I/O management
Memory and disc (files) management
UC process allocation and multiprogramming
6
SO TAXONOMY
OS classification after OS executable structure (cont)
kernel centered SO
kernel provides reliable communication
between server services and user calls
I/O separated by drivers
OS versions not necessarily involve
kernel stability, safety, versatility
client-server –with
host kernel (supervisor) and
server resource oriented and client modules (protected)
client call server services by message passing RPC
(distributed systems)
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SO TAXONOMY
OS classification after OS executable structure (cont)
virtual machines VM
the kernel covers (hide) the real (diverse H/W) machine
each real machine converted in std. VM
with special nest VM kernels over same real machine
you can install multiple virtual machines (VM)
each with its own resource management system (OS)
installed on the same core (HAL)
OS with each process with separate VM
runs in separate VM environment
nest VM kernel makes interprocess communication
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