Process Management Flashcards

In the output of 'ps aux', what does the 'S' state code indicate?

Answer: Sleeping (interruptible wait)

The 'S' state means the process is sleeping in an interruptible wait, ready to wake when its event or signal arrives.

What does 'ulimit -n' control for a process?

Answer: Maximum number of open file descriptors

ulimit -n sets the maximum number of open file descriptors a process can hold simultaneously.

Which system call does a process use to create a child process in Linux?

Answer: fork()

fork() creates a new child process as a copy of the parent; the child then often calls exec() to load a new program.

What does 'nohup command &' accomplish?

Answer: Runs command immune to SIGHUP and detached from terminal

nohup ignores the SIGHUP signal (sent when a terminal closes) and & puts the process in the background, so it survives terminal logout.

Which file in /proc shows a process's current memory map including shared libraries?

Answer: /proc/PID/maps

/proc/PID/maps lists all memory regions mapped by the process, including address ranges, permissions, and file mappings.

When using 'top', which key sorts processes by memory usage?

Answer: M

Pressing 'M' in top sorts the process list by memory (RES) usage in descending order.

What is the purpose of cgroups (control groups) in Linux process management?

Answer: To limit and account for resource usage by groups of processes

cgroups allow administrators to allocate, limit, and monitor resources (CPU, memory, I/O) for groups of processes, used heavily by containers.