Do you understand virtual memory versus physical memory? When a process asks for memory, especially huge chunks of it, one common strategy is to allocate a small part of it and then mark virtual memory (which is on disk usually) as allocated for the rest of the request.
See
Code:
free
swapon -s
Thanks for replying.
I have learned about different mapping methods of virtual memory to physical memory.
But whole physical memory is divided into two parts: one for Kernel, the other for User and usually 1:3.
For user part, user threads or processes share the physical memory by virtual memory mapping, so it means that each thread gets it memory without contention in the allocation even though they actually share the same physical memory? (I know the conflict can happen when they load their virtual memory segment to the physical memory area)
For kernel part, there is part of memory(For 4GB memory, it's 896MB) that can be used directly without mapping from virtual memory to physical memory. If parallel allocation happens in this area(such as parallel system call), will contention exist? If yes, how does it solve the performance problem?
Thanks
Hello!
First of all, forgive me for bad English.
When I starts new thread (pthread_create), system allocates some memory for it (for example, for thread's stack). I wonder when does it deallocate this memory? The problem is that I have a program which sometimes creates new threads and sometimes... (3 Replies)
Hi all,
I have a HP-UX Server with 4 gigabytes of physical RAM. When I use the 'Glance' utility to see what my memory utilization is, my memory usage shows up maxed out at 99%. I shut off all the known processes that I'm running on that box and the memory utilization is still at 78% (with Swap... (1 Reply)
Hi,
I am trying to process line by line of a file. But I should not be allocating static allocation for reading the contents of the file. The memory should be dynamically allocated. The confusion here is how do I determine the size of each line, put it into a buffer with the memory allocated... (11 Replies)
I have a program that will fetch some particular lines and store it in a buffer for further operations.The code which is given below works but with some errors.I couldn't trace out the error.Can anybody help on this plz??
#include <stdio.h>
#include <stdlib.h>
#include<string.h>
#define... (1 Reply)
I have a scenario like the client has to search for the active server.There will be many servers.But not all server are active.And at a time not more than one server will be active.
The client will be in active state always i.e, it should always search for an active server until it gets one.I... (1 Reply)
Hi Experts
I need some help in static memory allocation in C. I have a program in which I declared 2 variables, one char array and one integer. I was little surprised to see the addresses of the variables.
First:
int x;
char a;
printf("%u %u\n', &x, a);
I got the addresses displayed... (2 Replies)
Hello Guys
I have a small confusion in the dynamic memory allocation concept.
If we declare a pointer say a char pointer, we need to allocate adequate memory space.
char* str = (char*)malloc(20*sizeof(char));
str = "This is a string";
But this will also work.
char* str = "This... (2 Replies)
hi
in the following code, how the memory is allocated for a1 which holds the values of a2 after cpy function call.
#include <stdio.h>
#include <string.h>
void cpy(char* d, const char* s){
while(*d++=*s++);
}
main(){
char* a1;
char* a2="done";
cpy(a1,a2);
... (3 Replies)
I am using ubuntu. I have written a program to calculate prime factors. it works perfectly fine till entered number is less than 9989 (or so ) but when one enters a number higher than that, for example 15000, it does not work. Can anyone guide me whats the problem ? although new codes are welcome,... (2 Replies)
Discussion started by: Abhishek_kumar
2 Replies
LEARN ABOUT SUNOS
install-solaris
install-solaris(1M)install-solaris(1M)NAME
install-solaris - install the Solaris operating system
SYNOPSIS
install-solaris
install-solaris invokes the Solaris Install program. Depending on graphical capability and available memory at the time of invocation,
install-solaris invokes either a text-based installer or a graphical installer.
The following minimum requirements for physical memory dictate which features are available during installation:
For SPARC machines:
128 MB
Minimum physical memory for all installation types
128 MB
Minimum physical memory required for windowing system
384 MB
Minimum physical memory required for graphical-based installation
For x86 machines:
256 MB
Minimum physical memory for all installation types
256 MB
Minimum physical memory required for windowing system
512 MB
Minimum physical memory required for graphical-based installation
In some cases, even if the minimum physical memory is present, available virtual memory after system startup can limit the number of fea-
tures available.
install-solaris exists only on the Solaris installation media (CD or DVD) and should be invoked only from there. Refer to the for more
details.
install-solaris allows installation of the operating system onto any standalone system. install-solaris loads the software available on the
installation media. Refer to the for disk space requirements.
Refer to the for more information on the various menus and selections.
See attributes(5) for descriptions of the following attributes:
+-----------------------------+-----------------------------+
| ATTRIBUTE TYPE | ATTRIBUTE VALUE |
+-----------------------------+-----------------------------+
|Availability |SUNWcdrom (Solaris instal- |
| |lation media) |
+-----------------------------+-----------------------------+
|Interface Stability |Evolving |
+-----------------------------+-----------------------------+
pkginfo(1), install(1M), pkgadd(1M), attributes(5)
It is advisable to exit install-solaris by means of the exit options in the install-solaris menus.
23 Sep 2005 install-solaris(1M)
11-01-2017
