Task management and the Scheduler.

This is responsible for thread and process management. The functions performed include:
Thread and Process creation and termination.
Thread scheduling (priority and state management).
Preparing threads for dispatching.
Blockin and Running.
Implementing the Thread and Process related APIs.
The Scheduler's principle control blocks are:

PTDA

Per Task Data Area
TCB
Thread Control Block
TSD
Thread Swappable Data
TSS
Task State Segment (H/W)
System Loader
This is responsible for load module management. The Loader's principle responsibilities include:
Bringing modules into memory and performing fixups.
Managing modules resources.
Managing dynamic linking.
Tracking module references.
Deleting modules from memory.
Managing the discaring and swapping of module pages.
Implementing module related APIs.
The Loader's principle control blocks are:

MTE

Module Table Entry
SMTE
Swappable Module Table Entry
OTE
Object Table Entry
STE
Segment Table Entry
Memory Management
Memory Management is responsible for managing physical, virtual, and swapper memory. It's principle roles include:
Allocation and assignment of physical pages of memory.
Allocation and assignment of virtual storage.
Managing the swapper.
Memory locking.
Implementing memory related APIs.
The principle control blocks of Memory Management are:

VMAR

Virtual Memory Arena Record
VMOB
Virtual Memory Object Record
PF
Page Frame Structure
VP
Virtual Page Structure
PTE
Page Table Entry (H/W)
File System
The File System kernel component responsibilities include:
Access to FAT formatted media.
Interfacing with File System Drivers for accessing non-FAT media.
Managing and tracking the status of all open files.
Path Management
File sharing and serialisation.
Providing helper Kernel services for FSDs.
Implementation of all File System APIs.
The principle control blocks of the File System include:

MFT

Master File Table Entry
SFT
System File Table Entry
CDS
Current Directory Structure
FSC
File System Control Block
Device and I/O Management
This component is responsible for interfacing with Physical Device Drivers. Its responsibilities include:
Routing requests to PDDs from applications
Managing interrupts
Providing helper kernel services for PDDs.
The principle control blocks for device management include:

IRQI

IRQ Information Array
DIRQ
Device IRQ Information
REQ
PDD request Packet.
DEV
PDD device header.
Virtual Dos Machine
This component is responsible for providing the entire Dos Machine emulation. This has not been covered in this book, except for the Virtual Device Driver interface.

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