Virtual memory is a technique to provide more address space than the available physical memory. Each process can be given its own virtual memory, and the hardware translates every virtual memory reference to a physical memory address. To accommodate situations when more virtual memory is in use ...

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Swaping, Paging, Segmentation, and Virtual memory on x86 PM architecture

Well, this may seem a common or already asked question but after searching various books, online tutorials and even here on SU, I am still puzzled at how these four beasts work together on a x86 ...
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OS X virtual memory size can't be correct, can it?

I've got Snow Leopard and 8G of RAM. Activity Monitor reports a VM size of 173 *Giga*bytes. My hard disk is only 250G and 200G of that is in use. I've got a lot more data than 27 GB on my hard ...
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ulimit broke my server

I ran "ulimit -v 75" to get SBCL working, and now nothing will run on my server. $ sbcl Killed $ vi Killed $ man ulimit Killed $ ulimit -v 256 -bash: ulimit: virtual memory: cannot modify limit: ...
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Should I/Need I set the virtual memory on system parition or not?

I have a single drive(500Gb) divided into 2 partitions C:(98 Gb, system partition) and D:(368 Gb). Where should I set my virtual memory(manual input) ? Do need I to set it on system partition to ...
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imDisk: Create physical memory drive (not virtual memory drive) from command-line

I'm using imDisk (http://www.ltr-data.se/opencode.html/#ImDisk) to create a virtual drive in Windows 7. I use it as temp drive for documents and will be created every time the computer/windows ...
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Clarification of the difference between PCI memory addressing and I/O addressing?

Could someone please clarify the difference between memory and I/O addresses on the PCI/PCIe bus? I understand that I/O addresses are 32-bit, limited to the range 0 to 4GB, and do not map onto system ...
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408 views

Can we decrease page swapping? [duplicate]

Possible Duplicates: Windows Swap (Page File): Enable or Disable? Can we decrease page swapping? My system has a 5GB RAM. And my paging file size is 2GB Even though I have many RAM, ...
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501 views

Optimizing Windows XP to use less HD access

I have a corporate laptop with a great processor and 4 gigs of RAM, however the HD is ancient, we're talking 4200RPM here, roundabouts. Programs run great, but load horribly, horribly slow. Any ...
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18 views

How big are copy on write pages in linux?

We used RHEL 5.8 at my office. Our program relies on fork for parallelism. The application is very memory hungry (up to hundreds of GB) so we're relying on copy-on-write functionality to make this ...
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1answer
785 views

How can I configure Firefox to assume I have less memory?

Firefox has a few different settings that automatically get tuned based on the system ram. This is all great if you're running nothing besides Firefox, but when you're running half a dozen apps at the ...
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138 views

Does a storage HDD need a page file?

I've an HDD used only for storing files (i.e., not used for installing software). Do I need to set a page file for it?
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936 views

What's the virtual memory address space limitation of a Win32 application?

Below is what I understand, please correct me if i'm wrong about the 3GB part? a win32 application's virtual memory address space is limited by 4GB. Of the 4GB memory address space each process ...
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Disable virtual memory in Windows 8 is good?

I have an ultrabook hybrid with a SSD (mSata) and HDD working with intel rapid storage and my PC has 6 GB of ram. So I want to know if I can disable virtual memory and what other things should I do to ...
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662 views

On Linux there is a 3GB/1GB kernel option. How do I do this in Windows 7 32-bit?

I have 4GB RAM installed. PAE is off. How do I tell the Windows 7 32-bit kernel to allocate 3GB virtual paging area to user mode and only 1GB to kernel space?
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139 views

Do I need Readyboost and page file if I have lots of free RAM?

I have 12 GB RAM installed in my laptop. I have currently both page file and ready boost disabled. Most of the time my RAM usage are under 6 GB. So, I still have 6 GB RAM all the time. Considering ...
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598 views

Will increasing swap partition size increase the memory that can be used by a program?

I have a program that requires a lot of memory. So much that the malloc fails as the system goes out of memory. I don't care if the overhead for swapping pages in and out of the disk is too high - I ...
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2answers
104 views

Is it true to say that once I quit a process, the RAM used is immediately reclaimed?

I'm running Windows Vista Home Premium SP2 32-bit. Is it true to say that once I quit a process (Task Manager > Processes tab), the RAM used is immediately reclaimed?
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640 views

Killing Windows 7 process which is using memory - look at Commit or Private?

I'm trying to clear up memory usage on my windows 7 with 2 GB RAM Oracle.exe never shows up in the top processes, but the Resource Monitor shows it uses 637 Mb of commit (virtual memory) v 12Mb of ...
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511 views

What is commit charge?

Wikipedia says In computing, commit charge is a term used in Microsoft Windows operating systems to describe the total amount of virtual address space for which the backing store is the ...
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4answers
2k views

Will allocating too much virtual memory have any negative effect on your laptop?

Like will it slow down your boot-up? Also what problems will arise if you allocate more hard drive memory for virtual memory than what is available, will that cause any issues?
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292 views

Enormous virtual and private memory usage on a Windows 7 x64 Installation

recently my Windows 7 x64 machine started to act very weirdly, a lot of programs would crash randomly. The one application that would consistently crash was Team Fortress 2, after loading a map, I ...
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173 views

Why does Windows always use as much Virtual Memory as there is RAM installed?

And why does it want to have a maximum of twice as much of that amount? My System has 32GB of RAM and Windows, by default, sets a minimum of 16MB Virtual Memory, allocated 32GB(!) and recommends ...
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37 views

How to know the size of page frame used by my OS?

How to know the size of page frame used by my OS ? This could be useful for some optimizations when I code. (Allocate big buffer that fit in a page frame for example). Page frame is determined by ...
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392 views

Changing virtual memory using batch

I am making a program using batch to boost pc performance and I have now come to the stage where I need to edit windows virtual memory to a size that I can change in the code. if needed it can be done ...
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2answers
418 views

How does a software like cheat engine work?

I used to think that what cheat engine does is pretty much trivial: going to an address and simply modifying it but I realze now that things are not that simple. Each process has it's own virtual ...
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Virtual memory and commit charge

I've read a lot about commit charge and something still is bugging me. On my mac (and probably on linux too), what is the relation between VM size and and Commit memory (windows). I think I fully ...
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687 views

Linux Virtual Memory/Swap isn't being used

I think my virtual memory is not configured correctly on my MintLinux machine. I opened up a new IDE, IntelliJ IDEA, and my whole system appeared to freeze. I tried to TTL to the console but that did ...
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Windows application to monitor virtual memory activity

Is there a windows application that shows a graphical representation of virtual memoey, along with which pages are resident, which are being moved in or out, and so on. What I"m looking for is some ...
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458 views

What memory statistics does Linux' ps command really display?

Consider the following pmap output of a simple tail process on Linux: $ pmap -x 3974 3974: tail -F /var/log/syslog Address Kbytes RSS Dirty Mode Mapping 0000000000400000 60 ...
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Reducing both pagfile.sys and hiberfil.sys in Windows 7

I recently used Defraggler to consolidate my free space areas on my D: drive preparatory to using Disk Manager to break my drive into two areas, one as my "data area" for Windows 7 (normally on my C: ...
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297 views

Is virtual memory related to virtual address space of a process?

I have understood that Paging is a memory management technique which allows computer to bring data from secondary storage to main memory for executing process. It gives an impression to process that ...
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1answer
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Need for page file with 12 GB RAM [duplicate]

Possible Duplicate: Windows 7 pagefile size with large RAM and SSD I recently got my new PC with 12 GB RAM (running Windows 7 64bit). The default installation suggests a 12 GB page file on ...
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Force a process to run in virtual memory? Ubuntu

I am running a series of tests for an implementation of a remote pager that sends page faults to other computers in a network. Long story short, I was wondering if there is an easy way to force a ...
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tweak windows 7 virtual memory and cache / caching settings

im on windows 7 64 bit, with 4gb of memory whenever i copy or deal with a big ammount of data, windows swaps out everything from memory to the virtual memory swapfile, to make room to data cache. ...
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How can I see the correct “private bytes” value in process explorer?

I have a process that intentionally uses large amounts of memory. When I view this process in Process Explorer's list view with all memory-related columns enabled, this is what I see: Note that all ...
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28 views

Is there a way to choose which applications go to virtual memory?

The way I understand virtual memory is that when an application is not being used for a period of time, the memory being used gets written to disk. When I use an application (netbeans), it seems to be ...
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30 views

Virtually Indexed Physically Tagged Cache

I have been going through the four types of data cache used in virtual memory, I came across this problem and I could not solve it. Consider a Virtual Memory system with 20-bit virtual byte address, ...
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68 views

Windows tells me there isn't enough memory and asks to close Firefox, but why this actually happens is unclear

My system has 4GB of physical memory, and a system managed paging file on an SSD. It seems like the paging file's size is capped to 12GB for a total of 16GB memory, which should be more than enough, ...
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2answers
185 views

Best Settings for Windows 7 PC with lots of memory and CPU [closed]

I have a PC with Windows 7 Ultimate (64Bit) with 24 GB of ram and Intel i7 X980 (6 Cores). I would like to know, what are best settings/tweaks I should have for faster performance and efficient ...
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181 views

High latency when writing big files. How to prevent more-than-second page faults when quickly filling up FS?

When I do cat /dev/zero > /some/file all processes tends to become slow (even non-IO related). latencytop shows "Page Faults" are more than 2 seconds. Swap is not used. Adjusting vm.dirty* does ...
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0answers
987 views

16GB RAM. Is it OK to turn off virtual memory? [duplicate]

Possible Duplicate: Do I still need to use virtual memory? I have a windows 7 64 bit machine with 16GB. Memory usage will never reach anywhere near that. Therefore I don't see why Windows ...
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0answers
334 views

improving swapping strategy

I'm finding linux's swapping strategy to be somewhat less than ideal. In general I have a ton of processes running, maybe 40 or more big ones, and only end up using a few regularly. Nonetheless, I ...
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229 views

swapping or trashing with vast amounts of unmapped pagecache

I'm using kubuntu jaunty (i386 32bit), kernel 2.6.28-13-generic. I've 4Gb of RAM, of which only 3317Mb are seen by the system (I guess because of the 32bit system). I'm seeing that the pagecache ...
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6answers
3k views

How much RAM will Windows 7 consume or reserve for cache if I install 16 GB of RAM? [closed]

I have a pc with 4 gb of ram. I am thinking of buying 16 gb of ram because it might help windows 7 cache more "stuff" and I would browse stuff faster and maybe it would allow games to cache all data ...
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5answers
150 views

Why aren't all the disks contents in virtual memory?

For simplification let's only talk about hard disks and RAM. In a nut shell, virtual memory is when "memory addresses used by a program.. [are mapped] into physical addresses in computer memory". By ...
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3answers
82 views

How to increase swap memory in Windows? [duplicate]

I bought a new system with 4 GB of RAM. I don't know how do I check how much swap memory I have allocated. I know that we can increase RAM physically. I want to increase swap memory on windows. How ...
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97 views

Is that true that Windows can eventually address executable files as if they were parts of virtual memory?

I've once read somewhere that Windows can treat programs' executables and DLL files as parts of swap file rather than duplicating their content into pagefile.sys when swapping them out of physical ...
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489 views

sizes of RAM, of virtual memory and of swap for 32-bit OS

If I understand correctly, a 32-bit OS (Ubuntu) can only address 4GiB memory, so RAM with size larger than 4Gib will only be used 4Gib of itself and the rest is a waste. I am now confused about this ...
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6k views

Can Windows 7 pagefile be turned off if 4GB of hi-speed RAM present? [duplicate]

Possible Duplicate: Any reason not to disable the Windows pagefile given enough physical RAM? I believe that there is enough of memory for everything used at the moment to be stored and ...
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2k views

Virtual memory usage vs resident set size

When I launch php-script and do ps aux and have huge number for VSZ, about 450MB. Whilst RSS -- Resident set size -- is about 10MB. From wikipedia, Resident set size is is the portion of a process's ...