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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C program error in gcc compiler using ubuntu [on hold]

I ran c program using gcc compiler in Ubuntu 12.04 but whenever i run my program it shows virtual memory exhausted error to me through Ubuntu terminal. Please help.
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32 views

Recommended paging file size formula

Is there a formula by which Windows calculates recommended paging file size? (see picture). This is definitely not 1,5 x RAM (this PC has 8 GB or RAM). I need to implement this calculation in my ...
2
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1answer
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 ...
0
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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 ...
2
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2answers
26 views

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 ...
0
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1answer
42 views

Why memory can't be collected cleanly after a process terminats?

After long time running, computers always become slow. Rebooting generally make them faster. But how does this happen? Initally I thought this might be related to memory usage. But recently I learned ...
0
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0answers
43 views

What is the exact difference between the parameters (pgpgin, pswpin) and (pswpout, pgpgout) in /proc/vmstat?

Please note that this question is specific to linux only. And by swap space, I mean the dedicated swap partition. I did google a bit on this, and found these definitions: Paging refers to writing ...
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0answers
12 views

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 ...
1
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1answer
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 ...
0
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0answers
16 views

Cannot start site on IIS-Express

Some background: I Am developing a website that uses a BI layer that relays on Matlab. In order to make the logic layer available across my site I am creating it when the site starts (in ...
1
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0answers
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 ...
1
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3answers
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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1answer
205 views

How to increase Virtual Machine disk space?

I am trying to increase the available disk space of the VM, but no use, tried many things written here and on other websites, mainly saying that this is possible through the Virtual Media Manager , I ...
1
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0answers
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, ...
5
votes
2answers
282 views

What is the difference between virtual memory and built-in memory (RAM)?

I allocated ~24GB of my hard-drive as "virtual memory" -- what I understand to be extra space that the computer can use as RAM. My system has 8GB RAM built in, so my assumption is that I'm pumping a ...
1
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1answer
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 ...
0
votes
1answer
26 views

what is a word-length boundary?

I'm reading this article: http://en.wikipedia.org/wiki/Struct_%28C_programming_language%29 And it states the following: "The C struct directly corresponds to the Assembly Language data type of the ...
0
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0answers
63 views

Windows 8 will not boot after set virtual memory to 9999MB

To increase the performance of an ASUS X551M I increased the virtual memory 9999MB. In the past I would determine the max available virtual memory by typing in 9999. I expected to see something like ...
0
votes
1answer
49 views

I want to increase the swappiness in my windows 7

as I have 60% RAM usage every time. I have already increased Virtual Memory (Increased Swap Size) but want to increase swappiness too. see my RAM usage:
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0answers
28 views

Prevent a closed source chosen process from swapping on Windows [duplicate]

When I run VirtualBox If I don't use VirtualBox for some time and then I come back to using it the virtual machine runs very slowly, obliviously all subsequent operation go enough fast. How I can ...
1
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0answers
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, ...
0
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0answers
15 views

Hardware support of windows 7

To accomplish the mapping of process memory, perhaps virtual, hardware support is often used. This is normally done via process base registers. The windows 7 operating system may also need base ...
0
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0answers
18 views

Why was overlaying suppose to be done by the programmer?

I was reading about OS memory organization, and the first entry in the Virtual Memory(VM) chapter refers to overlaying and how when it was used at a large scale (up to the 60s) the process memory ...
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0answers
29 views

virtual memory view in windows server 2008

AFAIK, Task Manager in windows 2008 shows the physical memory. I have a program that sums up the FREE physical & FREE virtual memory in MG. How can I confirm it has the right output of this sum? ...
0
votes
1answer
51 views

Is CPU cache (L1 - Ln) equal to TLB

If we are talking about CPU cache. Is Ln synonym for saying 'TLB (translation lookaside buffer) of type Ln' or does Ln include also somethin else than just TLB?
0
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1answer
129 views

Windows - How can I flush modified memory?

This is a follow up on my previous question, here: Windows modified memory without a pagefile - Super User I have no pagefile and a lot of modified memory according to resource monitor (Win 7 x64). ...
0
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1answer
76 views

Windows modified memory without a pagefile

How does Windows' modified memory work without a pagefile? The physical memory is modified and then...? I'm running Windows 7 with 16GB of RAM and no pagefile. I have about 2.5GB of modified memory, ...
2
votes
2answers
829 views

Why does increasing Virtual Memory not helping game performance? [closed]

My RAM has a pathetic 2GB and most of my applications and background services take up at least 25% to 35% of it and thus causing the game to be laggy and all. I've tried adding virtual memory, from ...
1
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1answer
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 ...
0
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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 ...
0
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0answers
26 views

Copy a page from page cache to kernel space

Is the page cache part of the kernel space or user space? If I need to copy a page from page cache into the kernel space, what is the correct way to do it?
1
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3answers
2k views

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 ...
0
votes
2answers
104 views

What is the point of loading a program into RAM if virtual memory is just going to put it back on the disk?

After reading this question about virtual memory, I was inspired to ask: it seems like walking in a circle when a program is run it is loaded into memory from disk but then there's not enough space in ...
3
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3answers
172 views

Can anyone explain what is virtual memory?

In my system I am getting an error like "virtual memory is full". Can anyone explain to me what "virtual memory" is and how to fix that issue?
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1answer
514 views

Virtual memory (caching) on Windows 8

I have read a bit about the issue, and I understood that the OS constantly pushes memory to the disk, so later, when another application needs a lot of RAM, it allocates that memory to it and "moves" ...
0
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1answer
176 views

Turn off single process swap and overcommit

Two questions: Is there some way to turn off swapping for a given process, i.e., is it possible to kill a certain process if it uses all the system's primary memory available? How do I deactivate ...
1
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1answer
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 ...
2
votes
1answer
2k views

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 ...
0
votes
1answer
79 views

Linux virtual memory consumption after parsing log file

I wrote a parser to read the auth.log. For some reason while parsing auth.log I get that VSZ is larger than the total physical memory, which is 2GB. Depending on the size of auth.log and how long ...
0
votes
0answers
4k views

Create a Virtual USB disk drive and connect it to Virtual Box

I have created a virtual USB removable disk using imdisk http://www.ltr-data.se/opencode.html/ using commands http://diddy.boot-land.net/firadisk/files/imdisk.htm but How I can mount it to Virtual ...
0
votes
2answers
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 ...
0
votes
2answers
69 views

When is virtual memory not so virtual anymore?

On Windows, Mac & Linux there's virtual memory underway for every application software process in a RAM stack. But in regards to the actual use of my memory accessing data types, where exactly ...
0
votes
1answer
1k views

Top command cache vs free memory

When I am running top command (on embedded system with 64 MB RAM) I am getting below description on total memory usage: "Mem: 43468K used, 968K free, 0K shrd, 1280K buff, 21896K cached" It looks ...
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votes
1answer
65 views

Allocation of memory to guest os [closed]

I have 6gb memory on my host OS (Windows 7 64bit), I am planning to install Oracle Linux as guest using Virtual Box. How much memory should I allocate to guest OS? In guest OS I am planning to ...
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votes
2answers
370 views

Why does the Windows Task Manager never show more than 80% memory used?

In the Windows Task Manager I have never seen the memory usage close to 100%. If physical memory is never depleted, how come computers have virtual memory? I realize many years ago maybe computers did ...
1
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2answers
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?
18
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4answers
3k views

Why does Linux use a swap partition when the kernel supports paging/virtual memory anyway?

As far as I understand paging and swapping, they're completely different concepts. While swapping means, that a process is either completely in physical memory or on the hard drive, with paging parts ...
0
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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 ...
1
vote
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 ...
12
votes
5answers
1k views

Increase page file or buy RAM?

I've a 10+ year old XP PC which surprisingly still works however one of the 256MB RAM finally died. Now I am left with just 256MB. As expected the PC became slower however when I tried to increase the ...