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Functions of Operating Systems

Tag: operating systems

Efficient Mapping (Full Virtualization) – Georgia Tech – Advanced Operating Systems

Efficient Mapping (Full Virtualization) – Georgia Tech – Advanced Operating Systems

As I mentioned in a fully virtualized setting, the guest operating system has no idea about machine pages. It thinks that the physical page number that it is generating, is the real thing. But it is not. And therefore, there is two levels of indirection, one level of indirection going from virtual page to physical […]

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Mouse Click Quiz Solution – Georgia Tech – Advanced Operating Systems

Mouse Click Quiz Solution – Georgia Tech – Advanced Operating Systems

As you may have guessed, the right choice is, the most clicked results in a CPU interrupt. That’s the first thing that happens, and once the interrupt has been delivered to the CPU, there are domino effects that may eventually result in some program running to read the spacial coordinates. But the thing that happens […]

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Large Protection Domains – Georgia Tech – Advanced Operating Systems

Large Protection Domains – Georgia Tech – Advanced Operating Systems

You may ask, what if the protection domain is so large that it needs all of the hardware address space? Maybe the file system code base is so big that it needs the entire hardware address space. Cannot share it with anybody else. Similarly, the code base for the storage module is so big that […]

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Code Usage by Exokernel Quiz Solution – Georgia Tech – Advanced Operating Systems

Code Usage by Exokernel Quiz Solution – Georgia Tech – Advanced Operating Systems

Here are a couple of examples. I’m sure that you may have thought of other examples as well. But packet filter is one thing that I mentioned already to you. And this is something that may be a critical component of performance for any operating system. And therefore, it might install a packet filter for […]

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Handling Page Faults Case 3 – Georgia Tech – Advanced Operating Systems

Handling Page Faults Case 3 – Georgia Tech – Advanced Operating Systems

The third case is where the faulting page is not available in the cluster memories at all. In other words, the only copy exists on the disk. So in this case, what has to happen is, when we have the page fault on node P for this x, we have to go to the disk […]

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Subcontract – Georgia Tech – Advanced Operating Systems

Subcontract – Georgia Tech – Advanced Operating Systems

The secret sauce that makes this dynamic relation between the client and the server possible is this mechanism called subcontract. It’s sort of like the real life analogy of off loading work to a third party, you know, you give sub contract to somebody to get some work done. That’s the same analogy that is […]

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Examples of Candidate Resources – Georgia Tech – Advanced Operating Systems

Examples of Candidate Resources – Georgia Tech – Advanced Operating Systems

You are thinking, wow this sounds tedious and not performance conscious if exokernel has to validate the key every time for the library to use it. Well, it depends on what we mean by a resource. Let’s look at some examples. Here is an example of a candidate resource, a TLB entry. TLB entry is […]

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Dynamic Management – Georgia Tech – Advanced Operating Systems

Dynamic Management – Georgia Tech – Advanced Operating Systems

To motivate the need for dynamic management of data and metadata, it’s useful to look at the structure of a traditional NFS server which is centralized. In a traditional centralized NFS server what you have is the data blocks are residing on the disks. So in the memory of the server, the contents include the […]

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Java Distributed Object Model – Georgia Tech – Advanced Operating Systems

Java Distributed Object Model – Georgia Tech – Advanced Operating Systems

The nice thing about the Java remote object model is that much of the heavy lifting that an application programmer has to do in building a client-server system using RPC. Things like marshaling, unmarshaling, publishing the remote object on the network for the clients to access. They’re all subsumed under the covers by the Java […]

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Utility Computing – Georgia Tech – Advanced Operating Systems

Utility Computing – Georgia Tech – Advanced Operating Systems

Now, if we peak inside the black box however, we find that it is not just Bala who is using the resources in the virtual platform, but there is also Piero and there is also Kim, and possibly others who are also running their own applications. Their own operating system on the same shared hardware […]

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