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Questions tagged [interrupts]

88 questions
50
votes
4 answers

How computers display raw, low-level text and graphics

My ever-growing interest in computers is making me ask deeper questions, that we don't seem to have to ask anymore. Our computers, at boot, as far as I understand it, are in text mode, in which a character can be displayed using the software…
Doddy
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39
votes
8 answers

What is the interrupt key for Linux command "less"

When you do shift-f with less, you can see the file update in real time, and you get the "Waiting for data...(interrupt to abort)" message. The updating works fine, but what is the interrupt? nothing seems to work (Ctrl-C, Esc, Ctrl-I etc). I always…
Daniel
16
votes
2 answers

What is the “System Interrupts” process in Windows?

My system is a notebook system with an AMD A10 5750m CPU, R9 M290X GPU, 8GB, 1TB. I’ve noticed a process that is always active called “System Interrupts,” in this moment, it consumes in average 1.5% of CPU. I’ve searched everywhere, but I have not…
Daniel
  • 264
16
votes
1 answer

What determines whether or not Caps Lock responds while the computer is frozen?

When a computer is not responding in some way, there are different levels of "frozen". For example, let's say I'm browsing the web on my PC... If the current browser tab stops responding (clicking/typing does nothing), perhaps the browser still…
Bort
  • 1,714
9
votes
4 answers

How does an OS communicate with other hardware components?

How can a program running on a CPU (mostly OS) access other PC hardware? Such as Graphic card, HDD and so? From what I read, in DOS, this was done using BIOS calls, specifically the INT instruction. But, the INT instruction should only jump to the…
Jack
8
votes
5 answers

CPU usage shoots to ~50% and stays there until suspended

This is the Windows Vista problem, seen, I think, mostly on dual processor laptops, where % CPU suddenly shoots to about 45% and stays there. Once this has happened, % CPU will never return to normal on its own, though, curiously, "sleeping" the…
Daniel R Hicks
  • 6,261
7
votes
2 answers

Guidelines for troubleshooting high interrupt rate

Sample readings: high or above normal interrupt rate (at idle), at approximately 1505/sec Information obtained from Process Explorer and Kernrate System calls approximately 6132/sec Context switches approximately 1584/sec Possible faulty hardware…
Aaron
  • 1,488
6
votes
2 answers

How does an operating system prevent an unprivileged process from executing a privileged instruction?

In Unix, if you are a guest user and did: chmod 777 / It would fail. But how does this internally happen at the hardware level? So far, I think this is what happens: The OS tries to execute that instruction. Information about permissions is perhaps…
learner
  • 568
6
votes
1 answer

Heavy CPU Usage for Interrupt

As a follow-up to the question Why can't my computer speed up again after closing large applications? … I used Process Explorer to check my PC. I found that there's an average 30-40% of CPU being used by Interrupt. Is that normal? If it is not…
lamwaiman1988
  • 2,791
5
votes
1 answer

Hardware interrupts and system unresponsiveness

Very occasionally, about once a week, my Windows Vista Business machine will completely lock up for anything between a minute and several minutes. Once this happens, it recurs more frequently until I reboot. Process Explorer reveals that during this…
Paul Lammertsma
  • 4,256
5
votes
2 answers

Can someone explain to me how the CPU finds the source of an interrupt in OS theory?

I am currently doing a module in Operating Systems theory and I have a few concepts that I am unable to grasp - would this be the right place to ask questions ? My main question is about interrupts. When the CPU detects that there has been an…
user54094
  • 371
4
votes
1 answer

How do hardware interrupts work compared to software interrupts?

To give you an impression of the level of detail I'm interested, one example. I know a system call ultimately leads to a trap which lets the processor store registers, switch to supervisor mode and perform an indirect jump. But that's only a…
wnrph
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4
votes
1 answer

Simulate keyboard interrupt to gracefully exit task in Windows?

I have a process that doesn't behave when I do a taskkill -f, but the only option taskkill gives me is to kill it with -f. When I have the exe running in the Command Prompt I can hit Ctrl + C twice and it exits gracefully with a keyboard interrupt…
V_H
  • 205
4
votes
2 answers

Diagnosing hardware interrupt process usage proble

I've got a 5 year old Dell Dimension running WinXP SP3 that's really chugging along - Process Hacker (and Windows Task Manager) both report abnormally high Interrupt CPU usage. This ranges from 10-70%. I've read some about DMA vs PIO problems -…
JDB
  • 685
4
votes
2 answers

Single core to Dual core and Interrupts

Does increasing the number of cores result in the increase in the number of interrupts that can be handled by that processor ?
Karthik Balaguru
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