Processes and execution.
WHAT HAPPENS WHEN A PROGRAM STARTS
Its file is read from storage Memory is allocated It becomes a process, scheduled by the operating system
WHAT A PROCESS IS
A running instance of a program, with its own memory.
WHAT A THREAD IS
A stream of execution within a process.
Several threads allow work in parallel within one program.
WHAT THE SCHEDULER DOES
Allocates processor time among processes.
WHY PROGRAMS APPEAR TO RUN SIMULTANEOUSLY
They alternate rapidly, and on multiple cores some genuinely do.
WHAT A SERVICE IS
A process running in the background, without a user interface, frequently started at boot.
WHY THAT MATTERS IN SUPPORT
Many functions depend on services, and a stopped service produces symptoms with no visible cause.
WHAT TO CHECK
Whether the relevant service is running.
WHAT A PROCESS CONSUMING EVERYTHING INDICATES
A fault, a loop, or legitimate heavy work.
WHAT TO ESTABLISH
Which, before ending it.
WHAT ENDING A PROCESS RISKS
Loss of unsaved work and, occasionally, data corruption.
