I would like to dedicate 8 GB of RAM instead of the full (12) for a very long computation, in order to use the remainder for another operation. Is it possible?
Is there maybe a MATLAB command that forces the maximum limit of memory usage?
I would like to work with 2 separate editors.
See here for a possible solution on "limit the memory of a process on windows":
Set Windows process (or user) memory limit
Matlab has no command to limit the memory usage, it will aquire as much memory as needed to do the computation. On some operating systems you can limit the memory usage, for example using ulimit on Linux. But be aware, when Matlab needs more than 8gb it will not be slow when reaching the limit, it will throw an exception and stop computing.
Related
I use the NW extension to generate small-world networks and make an experiment in behaviour space to control the . In the experiment, I set ["nb-nodes" 50 100 500] (nb-nodes: the number of nodes).
Everything goes well until n = 500. CPU usage is too high, causing the program to become unresponsive.But when I set a single simulation with n = 500 in the interface, it keeps working. Only when I try to do it in the behaviour space, it goes wrong.
How can I solve it?
solution：
Thank for advice of Jasper and Steve Railsback, it helps a lot :)
In the FAQ (http://ccl.northwestern.edu/netlogo/docs/faq.html#how-big-can-my-model-be-how-many-turtles-patches-procedures-buttons-and-so-on-can-my-model-contain) it says:
"If you are using BehaviorSpace, note that doing runs in parallel will multiply your RAM usage accordingly"
So I just reduce the parallel from 16 to 8, I know it will slow down the program, but at the same time it will also reduce RAM usage and it works.
Of course, change RAM is another way and it can fit higher calculating demand.
I agree that you should start with increasing NetLogo's memory allocation as directed in the FAQ that Jasper referred you to. (At least in Windows, you must edit the NetLogo.cfg file using administrator privileges.) You can start by doubling or quadrupling the allocation, but the only real limitation is how much RAM you have on your machine.
We keep notes and a publication on NetLogo performance issues here:
http://www.railsback-grimm-abm-book.com/jasss-models/
Was playing around with some larger data sets and noticed that VSCode only uses around 30% CPU and RAM.
Is there some way to increase it? Probably some configurations? Thanks
You can increase/decrease the available RAM for VS Code on its Settings. Go to File -> Preferences -> Settings, there you can type files.maxMemoryForLargeFilesMB and change the value for your desired maximum RAM.
Not sure which coding language are you using, but let's break your question in two parts:
How to use more CPU ? (Can Increase Performance)
By using multiprocessing apis, which can divide a given large data sets into smaller units to be processed by various CPU cores, it is like a master slave architecture, where each sub process will execute on separate core and at max it is driven by total number of CPU cores.
If number of data units is more than CPU cores, then it will context switch
How to use more RAM ? (Can Degrade Performance)
Why do you need to increase RAM usage, that will be anyway dependant on amount of data allocated by the program
You may plan to create multiple copies to have a snapshot for each thread, needn't then use mutex or lock, but generally not a good practice
Finally :
CPU and RAM will be used process that is executing, based on programming langiage not the VSCode which is just an editor
I have several "out of memory" problems using MATLAB. I don't understand exactly if Matlab can use (or not) all the ram memory of my computer. This is the problem: my computer has 4gb of ram memory and 2 gb for Swap memory (my OS is Linux/Ubuntu 12.10), but Matlab only uses up to 2.6 gb and then shows the warning: "out of memory".
Is it possible to fix this and allow Matlab to use all the "available" memory?
Thanks.
It sounds like you're running 32bit linux and or 32bit MATLAB.
If you allow for enough swap, a process can take up to its virtual memory address space worth of memory.
Generally for 32bit linux you're limited to 3gb of address space for any process (the last gb is kernel memory space). It's entirely possible, depending on usage patterns, that at 2.6gb the next request for memory can't complete because there isn't enough /contiguous/ memory to satisfy it. This is especially common when growing large arrays.
Upgrading to a 64bit version of linux/windows/macOS with 64bit MATLAB should solve this problem but even so, using 3gb+ of virtual address space on a system with 4gb of ram is probably going to start making things very slow.
Some googling brought up this:
MATLAB will use as much memory as your OS lets it use;
the only way to increase the amount of memory MATLAB can use is to reduce
the amount of memory occupied by other applications or to give the OS more
memory to partition out to the applications.
So no, there's no easy way to tell matlab to use more memory.
You either have to buy more memory, optimize your code, run your scripts/functions with less output to store at once or reduce memory usage by other procedures that are running.
Here are some helpful links though:
memory management functions
memory allocation
related discussion on the mathworks forum
I want to calculate 2 covariance matrices with size (10304,1034) and matlab creates the first one but when it runs the second command, this error occurs:
>> j=ones(10000,10000);
>> jj=ones(10000,10000);
??? Out of memory. Type HELP MEMORY for your options.
My laptop's RAM is 2GB, but it still has 1 GB free. I am using Windows 7 and 32-bit MATLAB 2009b.
How can I resolve this error?
A 10k-by-10k array of doubles uses 1e8*8 bytes, which corresponds to 800MB. MATLAB needs these 800MB to be contiguous. Most likely, your 1GB free memory is a little fragmented, so MATLAB cannot fit the new array into RAM.
Use the command MEMORY to find out the maximum variable size that MATLAB can handle at a given moment.
Try to use sparse matrices, in that case MATLAB doesn't allocate the entire space.
Try any of these two options little bit increase in memory allocated for matlab.exe processing.
1- Give higher priority to Matlab.exe task. You can do that by going to task manager, Processes tab, right click the Matlab.exe Task, select priority and set it to higher priority (say real time), this tells Windows to allocate more resources to this process.
2- Increase the page file size of your applications in general. You can do this by right clicking MyComputer ->properties->Advanced System Settings ->Advanced-> Performance->Virtual Memory (change..). Then the tick from the Automatic .... and set the initial and maximum page size to say 10000 MB.
Go to Matlab-->file-->Preferences-->general-->Java heap memory--> and increase the level.. This solved my problem
When I run a sample script in MATLAB, it says:
Out of memory. Type HELP MEMORY for your options.
When I type "memory", it reports:
Maximum possible array: 156 MB (1.638e+008 bytes) *
Memory available for all arrays: 740 MB (7.756e+008 bytes) **
Memory used by MATLAB: 1054 MB (1.105e+009 bytes)
Physical Memory (RAM): 3070 MB (3.219e+009 bytes)
* Limited by contiguous virtual address space available.
** Limited by virtual address space available.
Is there any way to get around this error? I'm using Windows XP x32 with MATLAB 2009a.
pack does a memory defragmentation. It might help you a bit as far as the contiguous memory available.
Remember, when MATLAB says it's out of memory, it means it's out of contiguous memory, so rebooting or restarting MATLAB may work.
But, I'd recommend optimizing your code and identifying how you're eating up so much memory. It could be an ill-designed recursive loop, or a bad indexing function (using doubles instead of logicals to index a huge matrix).
I practically lived with memory errors for a while since I was dealing with huge datasets, but there's always a workaround, ask specific questions and you'll be surprised.
Problem fixed.
Under Windows XP x32, I managed to almost double the amount of memory available to MATLAB by editing boot.ini to add the switch /3GB /USERVA=3030
[boot loader]
timeout=30
default=multi(0)disk(0)rdisk(0)partition(1)\WINDOWS
[operating systems]
multi(0)disk(0)rdisk(0)partition(1)\WINDOWS="Microsoft Windows XP Professional" /noexecute=optin /fastdetect /3GB /USERVA=3030
Together with reducing our array sizes, this completely fixed the problem :)
I could have also fixed the problem by upgrading to Windows x64 or Windows 7 x64. This act also doubles the amount of memory available to MATLAB, even if you stick with MATLAB x32 and don't upgrade to MATLAB x64. Windows x64 is just far more memory efficient, even with systems that only have 4 GB of physical RAM installed.
Try this, it works well for me.
Go to Home -> Preference icon -> General -> Java Heap Memory -> Allocate what size of memory you want
In Preference window, go to "Workspace" (out of Java heap memory level) -> See "Matlab Array size limit"
Make sure uncheck the 'Limit the maximum array size to a percentage of RAM'. Because you want to extend memory
so we don't need this feature.
Done.
What are you attempting to allocate when it runs out of memory (OOM)? Do you have code to reproduce? A wide range of problems can cause out of memory errors.
To diagnose, use "dbstop if all error" to set a breakpoint on errors. The out of memory will trigger this, and you can use dbup, dbdown, and whos() to see what's consuming memory. Often an OOM is caused by a bad array size or index calculation, not just by big data structures. E.g. this will trigger an OOM in pretty much any 32-bit MATLAB.
>> x = 1;
>> x(2^30) = 2
??? Out of memory. Type HELP MEMORY for your options.
I faced a similar error while running an (old) C file in MATLAB using mex.
I found my solution at this issue on GitLab.
First, uncheck the option "Limit the maximum Array Size to a % of RAM" located under Preferences -> Workspace, as also indicated in this earlier answer.
Once applied, run your C file in the command window using
mex filename.c -compatibleArrayDims