2
votes
1answer
110 views

Can a kernel that supports multi-core reduce cpu overhead, reduce cpu overheat

I found only a single core as identified by kernel from /proc/cpuinfo. Therefore I am installing a 686 pae kernel to identify all cores and get multi-core functionality. I read about how a process ...
2
votes
2answers
70 views

Library functions are always implemented using system calls?

We know that system calls are requests by a process for a service from an operating system's kernel.[1] I'm asking this question because I wanted to know if a process can really generate a signal on ...
5
votes
4answers
182 views

Does the kernel process need to save something when switching to user mode? [closed]

According to my professor, "while switching from user mode to kernel mode, the status of the user process has to be saved completely. But when switching from kernel mode to user mode, nothing has ...
0
votes
1answer
158 views

Possibly infected kernel (odd system process) [duplicate]

Possible Duplicate: What to do if my computer is infected by a virus or a malware? Has anyone seen/or knows anything identical to this: 1515..:19699.exe with a semicolon in the center? ...
-1
votes
1answer
754 views

Clarification on diagram about OS and user processes

I was looking at different relationships that can exist between an operating system and a user process. I came across the figure below. It shows an architecture where the OS functions execute with ...
2
votes
2answers
1k views

How does 'strace' work?

Recently, I was using mv to move a large amount of files from my hard drive to a flash drive. I forgot to add a verbose flag so I had no idea "where" the move was at and how many transfers remained. ...
6
votes
3answers
1k views

Kernel and User mode distinguishing

Who is responsible for determining that the process is in the Kernel mode or User mode? I know kernel knows which process is belong to what space, but how the CPU determines that? I mean should CPU be ...
2
votes
3answers
445 views

Does a software like VMware run in user space or kernel space?

Vmware is a user installed software. So it should run in user space given by the underlying OS. Yet its runs OS-es which are fully operational and need to run in kernel mode. So where does it run?
1
vote
1answer
257 views

Implication of variable context switching time

I know that constant switching time of the Linux scheduler was a big achievement. What would be the implication of a non-constant switching time? The only obvious reason I can think of is ...
4
votes
5answers
1k views

In linux, what would happen to a running program when it's executable file has been modified, or deleted

Let's say /usr/local/bin/ruby is running in the background, and then we overwrite ruby with a different version, or even delete ruby. What will happen to those running ruby processes?