1
vote
1answer
62 views

Limiting processes by memory under Linux

We must launch several hungry processes on a Linux system. These processes often need several Go (~5Go) of memory to run (total memory: 16Go RAM + 2Go swap). At first, when the system was running ...
2
votes
2answers
129 views

lsof - debug the output information

I was going through the questions of this site. In this particular question, I see the command lsof being used to list the files that are open for a particular user. I ran the below command in my ...
2
votes
2answers
127 views

How does a process handle the situation when it finds no memory to use?

What happens when a particular process finds that there is no memory to use? Will that process kill/restart another process to proceed their task ? Or what the process (that requires more memory) ...
2
votes
2answers
132 views

a handy tool to measure memory consumption of a program [duplicate]

I develop a C code on Debian. I am looking for a program to monitor memory consumption of my code in real-time. The only value I care is the maximum RAM consumption, it should hold the value even if ...
0
votes
2answers
131 views

what is an application pool?

I'm reading this article: http://www.modrails.com/documentation/Architectural%20overview.html#web_app_models It talks about how Phusion Passenger extends Apache2 to act as an application server. ...
0
votes
1answer
89 views

What is meant by “a process has open handles to system objects”? [closed]

The following are qualities of a process: virtual address space executable code open handles to system objects a security context a unique process identifier environment variables a priority class ...
3
votes
3answers
59 views

Contents of stack area of a process

I've been going through some Unix text books and I can't have a clear picture on the contents of the stack area of the process. Can anyone please explain or point out some references?
2
votes
1answer
184 views

pmap and memory usage

On Ubuntu 12.04, I have several apache2 processes running (the 1130 parent and the children it spawned), and as you can see, they have around 300-400 mb of virtual memory and 10 mb of resident memory: ...
4
votes
2answers
292 views

Turning off swapping for only one process with cgroups?

I would like to turn off swapping for only one process. Swap should work as usual for the other processes. How I can implement this with cgroups?
1
vote
2answers
187 views

process memory usage

What is usually meant by the phrase process memory usage, what does this actually mean, i.e. what does this memory consist of? And what column does it correspond in ps aux output, RSS or VSZ?
2
votes
1answer
4k views

How to find Heap memory of a running process? [duplicate]

I would Like to know how to find the heap captured of a process which is running in the background? Is there any command by which you can find the process heap memory and here the process is still ...
1
vote
1answer
112 views

Looking for /procfs documentation, describing values and units of measurement

Surprisingly, comprehensive documentation for /procfs is hard to find. For my specific question, I am looking at: cat /proc/1/statm (let's use pid=1 because it seems to be always there). I just ran ...
3
votes
2answers
225 views

Where is the virtual memory stored on hard drive?

If a process wants to access a memory address that is not in physical memory, the OS outsources a page frame from physical memory to the hard drive for later use. Where on the hard drive is this data ...
4
votes
2answers
807 views

What is “automatic stack expansion”?

getrlimit(2) has the following definition in the man pages: RLIMIT_AS The maximum size of the process's virtual memory (address space) in bytes. This limit affects calls to brk(2), mmap(2) and ...
1
vote
2answers
676 views

Discrepancy between reported used memory and sum of application memory usage

I'm running a desktop system that quite regularly suffers from lack of memory, this prompted me to investigate what causes the issue in the first place. Problem is, there's no single process that ...
2
votes
2answers
913 views

Find the PID of top CPU/MEM usage, save to a shell variable

Is there any way to get the PID of the top CPU/MEM usage, I need to use that in a script, top command doesn't seem to work for it.
0
votes
1answer
2k views

How to know maximum memory usage of a process? [duplicate]

Possible Duplicate: Measuring RAM usage of a program I have a process, which is quite short-running (about 10 minutes), but memory heavy. I want to know how much memory does the process ...
3
votes
1answer
405 views

Rationale for making user space text segment start at 0x8048000

I read somewhere that (at least since Linux v. 2.6) all user-space code is placed at load address 0x8048000 in the virtual memory address space. My own observations confirm this. I have done a cat ...
7
votes
1answer
7k views

Need explanation on Resident Set Size/Virtual Size

I found that pidstat would be a good tool to monitor processes. I want to calculate the average memory usage of a particular process. Here is an example output: 02:34:36 PM PID minflt/s ...
2
votes
1answer
655 views

How often is PSS value updated for a given process in /proc/pid/smaps

So if n processes are sharing a library L with size M then the contribution to their PSS is M/n. Now imagine one of the process terminates. So the contribution would be M/(n-1). Q1: My question is ...
15
votes
1answer
9k views

Getting information about a process' memory usage from /proc/pid/smaps

For a given process in /proc/<pid>/smaps, for a given mapping entry what are: Shared_Clean Shared_Dirty Private_Clean Private_Dirty Is Shared_Clean + Shared_Dirty the amount of memory that ...
1
vote
3answers
112 views

What is the lowest level I can see my system running?

Let me try and clarify. Is there any way for me to see very very low level activity on my computer? Stuff like: register content opcodes being sent specific memory addresses Or anything lower ...
5
votes
4answers
2k views

Suspend/resume single process to/from disk

On occasion, we would like to suspend memory-intensive processes on our Ubuntu and OS X servers to temporarily free up some RAM for other jobs. If all we were worried about was CPU usage, a simple ...
5
votes
1answer
484 views

How can I search/browse in some process's memory?

I'm using MacOS X 10.7 and I'm not very familiar with unix. Is there a command for a search in some process's memory for a string?
18
votes
4answers
3k views

Measuring RAM usage of a program

time is a brilliant command if you want to figure out how much CPU time a given command takes. I am looking for something similar that can measure the max RAM usage of the program and any children. ...
3
votes
1answer
574 views

Solution to get data from memory of a process

If I'm using Firefox and filling out a big form (with lots of text to write), and for some reason I accidentally press F5 and all my text in the forms is lost, I can use e.g. HxD on Windows to ...
4
votes
1answer
1k views

Disable random memory address generation in my programs

I'm reading "The art of exploitation" and would like to try some experiments, including reading from and writing to various memory address. I've created some simple programs and trying to overwrite ...
3
votes
1answer
248 views

Linux system calls

I want to obtain information about memory used by different users and different processes which users are running and statistics about those processes like memory consumption ,execution speed etc ...
3
votes
2answers
717 views

Questions on Linux kernel internals

I was reading "Linux device drivers, 3rd edition" and faced a few kernel items I don't quite understand. Hope gurus on this forum will help me out. Does the Linux kernel internally operate with ...
52
votes
3answers
27k views

How do I read from /proc/$pid/mem under Linux?

The Linux proc(5) man page tells me that /proc/$pid/mem “can be used to access the pages of a process's memory”. But a straightforward attempt to use it only gives me $ cat /proc/$$/mem ...
5
votes
3answers
556 views

Is it possible to support multiple processes without support for Virtual memory?

Is it possible to support multiple processes without support for virtual memory? I would like to know more about it if so.
23
votes
5answers
34k views

How to find which processes are taking all the memory?

I'm looking for somthing like top is to CPU usage. Is there a command line argument for top that does this? Currently, my memory is so full that even 'man top' fails with out of memory :)
13
votes
6answers
4k views

Is there a way to limit the amount of memory a particular process can use in Unix?

I need to test a process for memory management. I do not have the source, so I need to do all the testing from the OS side. I want to be able to say something like limitmemory 400k -p <pid> ...