GUIDE: Understanding Virtual Memory / Increasing Virtual Memory

[brianc]

EDIT: Please +Rep if this helped. -Thanks

EDIT:
As Requested.
Source: http://cs.gmu.edu/cne/modules/vm/green/defn.html


Hello,

I have been seeing alot of complaints about game lag, or not being able to run the client due to low memory.

This is a tutortial that will fix that problem.

Enjoy.

   
Definition 

Virtual memory is a technique that allows processes that may not
be  entirely in the memory to execute by means of automatic
storage allocation upon request.  The term virtual memory refers to
the abstraction of separating  LOGICAL memory--memory as seen by
the process--from PHYSICAL memory--memory as seen by the
processor.  Because of this separation, the programmer needs to be aware
of only the logical memory space while the operating system maintains
two or more levels of physical memory space.
The virtual memory abstraction is implemented by using secondary
storage to augment the processor's main memory.  Data is transferred
from secondary to main storage as and when necessary and the data
replaced is written back to the secondary storage according to a
predetermined replacement algorithm.
  If the data swapped is designated a fixed size, this swapping is
called paging;  if variable sizes are permitted
and the data is split along logical lines such as subroutines or
matrices, it is calledsegmentation.  Some operating systems combine
segmentation and paging.   [S2]

   The  diagram illustrates that a program generated address ( 1 )
  or "logical address" consisting of a logical page number plus the
location within that page (x) must be interpreted or "mapped" onto an
actual (physical)   main memory address by the operating system using an
address translation function or
mapper  ( 2 ).  If the page
is present in the main memory, the mapper substitutes the physical page
frame number for the logical number  ( 3 ).  If the mapper
detects that the page requested is not present in main memory, a fault
occurs and the page must be read into a frame in main memory from
secondary storage  ( 4 , 5  ).
pp. 161-165
   What do you think are the main considerations in implementing this
virtual memory system?

 

Some error messages that require you to change the virtual memory settings:

“Your system is low on virtual memory” error message when you try to start an program

Changing the virtual memory settings in Windows XP:

1. Right-click and select Properties, OR Click on Start and then click Run and in the Box type: sysdm.cpl and press enter.

And then you will see this:



2. Click on the "Advanced Tab" and then click "Settings" like this :



3. Then click the "Advanced Tab" and by "Virtual Memory" click "Change" like this :



4. Then you can choose a custom size or let Windows choose. I recommend letting windows choose because changing it to a custom size is more for Advanced users. Then click "Set" and "Ok".
You can set virtual memory on each physical drive but not each partition.



5. Click ok when you see this:



6. Then click on OK in Virtual Memory window.

7. Then click on OK in Performance Options window.

8. Then click Yes when you see this:



Regards,
Brian Crowell

[Coleshot1]

"Oheylooky he made another topic.. And I just happen to need this one too. =O
This so isn't going to work."

Yes, I actually predict when these things won't work for me.

*Goes through instructions*
*Clicks "Set"*
"There is not enough space on this drive for the paging file size to be specified. Please enter a smaller number or free some disk space." And, there it is.
Like 300 something MB of free space, no wonder.
*Deletes cache(youtube videos), 400MB. *Not enough space*, *deletes Touhou+allgofree's Blitz files* 700MB. *Not enough space*

Well, I saw that coming.
My laptop has 7.2GB total space, 300-400MB on average free, 900 as a high-free. Yep, most ipods have 4 times the memory. At least.

I'll keep working on freeing more space, but really, it'd be less work to make $800 and buy a new laptop. Or, heck, an Ipod.(With more space of course)

[Drunk Mario]

Hmm.. I did this and i restarted my computer and all but then what? How can i use Virtual memory?

[Drunk Mario]

Its automatic.  :P

Good. That's nice and easy!

Oh my gosh! Thank you so much! i can play RSPS again and Worldscape! Thanks man! This party helped me.. I can play but i jsut lagg after a little bit thne have to log off the computer user then log back on.

[brianc]

No problem,

I'll be sure to make some more guides related on keeping your computer healthy.

Me being an IT Specialist, It's my job to keep everyone safe in the computer world.

Regards,
Brian Crowell

[Coleshot1]

Okay, now I just happen to have 1.52GBs of space..
It let me change it, I did the system-managed one, did OK and everything. It didn't ask me to restart my laptop.. I tried getting on Worldscape on the Low-detail client and I got the same Java Heap Size error.

I've seen at least 6 pages/site posts of increasing your Java Heap Size.. But it's always a code/script you have to type. I have no idea where to type it. >_>

Actually.. *Restarts laptop*

I'll see if this works. But anyways, where do they expect you to type
java -Xms<initial heap size> -Xmx<maximum heap size>
"(Defaults are:)"
java -Xms32m -Xmx128m
Though? I understand it for the most part (not sure what unit "m" is), but I don't know what program/whatever you'd type that in.

[brianc]

Okay, now I just happen to have 1.52GBs of space..
It let me change it, I did the system-managed one, did OK and everything. It didn't ask me to restart my laptop.. I tried getting on Worldscape on the Low-detail client and I got the same Java Heap Size error.

I've seen at least 6 pages/site posts of increasing your Java Heap Size.. But it's always a code/script you have to type. I have no idea where to type it. >_>

Actually.. *Restarts laptop*

I'll see if this works. But anyways, where do they expect you to type
java -Xms<initial heap size> -Xmx<maximum heap size>
"(Defaults are:)"
java -Xms32m -Xmx128m
Though? I understand it for the most part (not sure what unit "m" is), but I don't know what program/whatever you'd type that in.

They mean the Run.Bat of the program your trying to run.

Check their.

Also, if you need more help in Java, refer to my Java - JavaScript Guide: http://www.worldscapeblitz.com/blitz/smf/index.php/topic,7492.0.html

Hope I have helped.

Regards,
Brian Crowell

[Joker]

What should i do?
My computer is windows Xp

[brianc]

Change the Initial size to 3GiB.
Then press the set button.

This will make for the best results.

Regards,
Brian Crowell

[Joker]

thanks. :)

[Annakarl]

its cool man it really helped me

[brianc]

Hello,

Could I get my sticky back on my topic please? It was removed when my topic was moved.

Thanks.

Regards,
Brian Crowell

[Drunk Mario]

It doesn't need to be stickied, Only the Rules of this board need to be. I'm pretty sure no guides will be stickied here.

On topic: Great guide! It has helped me a lot! Thank you very much!

[Triniboy]

Although increasing Virtual memory helps speed up the computer, After a hour or two, It fills up, and you need to restart the computer to get back the space to re-use the Virtual Memory.

Also I heard of when setting the size of the virtual memory, Set the size to 1.5x (multiply) times the size of your physical RAM. Example if you have a PC with 2 Gigs of Ram, set the Pagefile size to 3000 Mb..ex 2,000mb x 1.5 = 3,000mb

[masterp82]

ohh w00t! this was very helpful, thanks!