Threads and Concurrency

These flashcards cover essential vocabulary related to threads and concurrency, providing definitions for key terms discussed in the lecture.

Concurrency

The ability of a system to handle multiple tasks simultaneously.

Thread

An execution flow within a process that can run concurrently with other threads.

Process

An instance of a program that is being executed, which may contain multiple threads.

Context Switching

The process of saving the state of a currently running process and loading the state of another process.

Kernel Level Threads (KLT)

Threads that are managed by the operating system's kernel.

User Level Threads (ULT)

Threads that are managed by user-level libraries without kernel involvement.

Thread Control Block (TCB)

Data structure in the kernel that stores information about a thread.

Shared Memory

An IPC mechanism where multiple processes can access the same memory space.

Fork

A system call used to create a new process by duplicating an existing one.

Exec

A system call that replaces the current process image with a new process image.

Thread-Local Storage (TLS)

A mechanism by which each thread can have its own separate copy of certain data.

Thread Pool

A collection of pre-initialized worker threads that can perform tasks efficiently.

Grand Central Dispatch (GCD)

Apple’s implementation of thread pools to manage concurrent operations.

Signal Handling

The process of managing signals, which are notifications sent to a process to indicate an event.

Thread Cancellation

The process of terminating a thread that is no longer needed.

Asynchronous Cancellation

A method where a thread is immediately canceled without any conditions.

Deferred Cancellation

A method where a thread is notified to cancel itself, which allows for safe resource management.

Many-to-Many Threading

A hybrid threading model where multiple user-level threads are mapped to multiple kernel-level threads.

One-to-One Threading

A threading model where each user thread corresponds directly to a kernel thread.

Many-to-One Threading

A threading model where many user threads are managed by a single kernel thread.