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Questions tagged [scheduling]

A technique for scheduling tasks to be run at specific time or on specific event.

63 questions
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How does Windows processor affinity work with hyperthreaded CPUs?

How does Windows processor affinity work with hyperthreaded CPUs? Let's use an example (pictured) of a system with four cores, each with a hyper-threaded virtual core. Which cores correspond to each "CPU" below? Does (say) CPU 6 and CPU 7 below…
Charles Burns
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Is there an rsync-like mode for WinSCP (or a similar tool)?

I need to be able to do a periodic sync of content off my Windows 7 x64 laptop to my offsite CentOS 6 webserver. Is there a tool/mode like rysnc for WinSCP or similar? For a variety or reasons, Dropbox is not an option here.
warren
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nice has no effect in Linux unless the same shell is used

If I enter in two different root terminals: nice -n 19 burnK7 & and nice -n -19 burnK7 & Then both processes receive about 50% of the available CPU time - not expected and certainly not desired. If I run in the same root terminal: nice -n 19…
Fela Maslen
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Linux/Bash, how to schedule commands in a FIFO queue?

I want the ability to schedule commands to be run in a FIFO queue. I DON'T want them to be run at a specified time in the future as would be the case with the "at" command. I want them to start running now, but not simultaneously. The next scheduled…
Andrei
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Scheduling algorithm used in Windows 7

What is the scheduling algorithm used in Windows 7?
arulappan
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Running a virtual machine on a dedicated processor or core

Our base system runs on Linux but unfortunately the UI has to be on Windows. Its a long story. But thats the requirement. So our idea was to run Windows in a virtual machine using VirtualBox or Xen. Because of our real-time performance constraints,…
Cocoro Cara
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Multicore system. How are the cores "sorted"

If I have a system with let's say two Quadcore CPUs and HyperThreading enabled, how do I know how the phsyical and virtual cores are sorted? For example if I force a process to run on "CPU 0" how to know which Core this really is? I remember a…
asdrubael
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Increasing value of sched_latency_ns and sched_min_granularity_ns

Why do I get an error message when I try to increase the values of these two parameters: #cat /proc/sys/kernel/sched_latency_ns 1000000000 #echo 2000000000 > /proc/sys/kernel/sched_latency_ns bash: echo: write error: Invalid argument # I get the…
Prasoon Tiwari
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Optimize linux USB hub IO scheduling for external harddrives

When using several harddrives on an USB 3.0 hub, copying large files between them gives transfer rates far below expectation. My guess is, that the hub introduces contention delays as we see if copying files inside a single harddrive. For example,…
dronus
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Does the Windows scheduler allocate equal length quanta to threads?

Is the time slice (quantum) that the Windows Kernel Dispatcher allocates to threads the same length for every thread, or does it base the size of quantum on the priority of the thread like Linux does?
user49786
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ALWAYS run commands with low priority on unix?

I am not asking how to nice and renice a command on UNIX. What happens is that on a particular machine into which I frequently log I am only allowed to run long-running processes with low priority (nice 19). Is there a way for all my commands on…
laramichaels
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Does an operating system itself take up resources (aside from the space it is installed on)?

I just finished a course on operating systems and the definition of an operating system is still unclear to me. Does any operating system itself take up resources such as CPU and memory? For example the scheduling algorithm must take some processing…
Celeritas
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crontab schedule rule misunderstanding

I've got some strange behavior of one rule working unexpected. */40 * * * * myshellcommand here I though it would run each 40 minutes, e.g. 00.00 00.40 01.20 02.00 etc but instead it runs 00.00 00.40 01.00 01.40 02.00 etc. Does anyone have an…
heximal
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CFQ hard drive scheduling algorithm

The CFQ algorithm uses an ordered set of queues based on the I/O priority of the processes that made the requests. That means there's a queue for process of priority, let say, 1, another one for priority 2, etc. Then the requests are placed into a…
Jcao02
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Can kvm guest get more CPUs than it has?

When I run a vm with a single virtual CPU inside KVM, is it possible that the vm can actually get more CPU cycles than one whole CPU can has, if there is no other vm running in the host? In another word, can the vm get more CPUs than it has? I does…
Zhen
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