Linux Kernels 2.6.16 and up provide a way to instruct the kernel to drop the page cache, inode and dentry caches on command. This tip can help free Linux memory without a reboot.
Note: This is a non-destructive operation. Dirty objects are not freeable, hence; you must run sync beforehand.
To use /proc/sys/vm/drop_caches, you simply echo a number to it.
For example if i have the piece of code as follows:
CountryName = (char *)malloc((strlen(CountryName)+1)*sizeof(char));
memset(CountryName, 0, strlen(CountryName)+1);
CountryName = SOME VALUE
Now how do i free the memory after use of this code???? :confused: (3 Replies)
HI
I'm a rookie in C programming and I'm working in Monta Vista Linux. I have to write a program that displays free memory. I have memtester(allready written by someone else) and now I have to type how much amount of memory tester will test and I want that memtester finds out himself how much of... (11 Replies)
Hi,
I am facing one problem, On our Linux server Free memory decreases gradually but my java process memory does not increase.
Please any one tell, why free memory decreases gradually (1MB in approx 15 minutes).
kernel details:-
Linux linux4 2.6.9-42.ELsmp #1 SMP Wed Jul 12 23:27:17 EDT... (13 Replies)
Hi,
Im working on Solaris 9 on SPARC-32 bit running on an Ultra-80, and I have to find out the following:-
1. Total Physical Memory in the system(total RAM).
2. Available Physical Memory(i.e. RAM Usage)
3. Total (Logical) Memory in the system
4. Available (Logical) Memory.
I know... (4 Replies)
Hi all,
Could please let me know how to get the more memory free space (not added the RAM) in local zone.
-bash-3.00# vmstat 2 5
kthr memory page disk faults cpu
r b w swap free re mf pi po fr de sr s0 s1 s1 s1 in sy cs us sy... (3 Replies)
hi, I have done the below, but am confused as to how much memory is "free"
please help
thanks
$ free
total used free shared buffers cached
Mem: 132033488 48827536 83205952 0 1007696 45404632
-/+ buffers/cache: 2415208 ... (7 Replies)
I was running a program and it stopped and showed "Out of Memory!". at that time, the RAM used by this process is around 4G and the free memory size of the machine is around 30G. Does anybody know what maybe the reason? this program is written with Perl. the OS of the machine is Solaris U8. And I... (1 Reply)
hi- im running glassfish 3.1 on debian server and there are times where I need to start the domain when we cannot access the web application. I checked the memory and it's confusing me. Am i still ok? can you explain the below?
USER PID %CPU %MEM VSZ RSS TTY STAT START TIME... (1 Reply)
Hi guys.
I've a question, if we are using a syscall that receives a string allocated dynamicaly to a determined size, or NUL and it will allocate the apropriate size. We should free the memory or the OS will do it for us?
If a function returns a pointer we should free that poiter when we are done... (7 Replies)
Discussion started by: pharaoh
7 Replies
LEARN ABOUT OPENSOLARIS
sync
sync(2) System Calls sync(2)NAME
sync - update super block
SYNOPSIS
#include <unistd.h>
void sync(void);
DESCRIPTION
The sync() function writes all information in memory that should be on disk, including modified super blocks, modified inodes, and delayed
block I/O.
Unlike fsync(3C), which completes the writing before it returns, sync() schedules but does not necessarily complete the writing before
returning.
USAGE
The sync() function should be used by applications that examine a file system, such as fsck(1M), and df(1M), and is mandatory before
rebooting.
ATTRIBUTES
See attributes(5) for descriptions of the following attributes:
+-----------------------------+-----------------------------+
| ATTRIBUTE TYPE | ATTRIBUTE VALUE |
+-----------------------------+-----------------------------+
|Interface Stability |Standard |
+-----------------------------+-----------------------------+
SEE ALSO df(1M), fsck(1M), fsync(3C), attributes(5), standards(5)SunOS 5.11 5 Jul 1990 sync(2)