Threads The thread defines a sequential execution stream within a process. Processes The process defines the address space and general process attributes (everything but threads of execution) Kernel-level thread OS-managed threads are called kernel-level threads or lightweight processes. Thread operations still require system calls Kernel-level threads have to be general to support the needs of …
Notes on “Process” and “Process API”
Process The abstraction provided by the OS of a running program is something we will call a process. The process is the OS abstraction for execution A process is sometimes called a job or a task or a sequential process A sequential process is a program in execution A process contains all state for a …
Notes on “Mechanism: Limited Direct Execution”
Architecture must support (at least) two modes of operation: Mode is indicated by a status bit in a protected control register User programs execute in user mode OS executes in kernel, privileged mode (OS == “kernel”) User mode code that runs in user mode is restricted in what it can do. For example, when running …
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