The first row, labeled Mem, displays physical memory utilization, including the amount of memory allocated to buffers and caches.
A buffer, also called buffer memory, is usually defined as a portion of memory that is set aside as a temporary holding place for
data that is being sent to or received from an external device, such as a HDD, keyboard,
printer or network.
The second line of data, which begins with -/+ buffers/cache, shows the amount of physical memory currently devoted to system buffer
cache. This is particularly meaningful with regard to application programs, as all data
accessed from files on the system that are performed through the use of read() and write()
system calls1 pass through this cache. This cache can greatly speed up access to data
by reducing or eliminating the need to read from or write to the HDD or other disk.
I'm looking to get the file cache portion of physical (real) memory on a Solaris workstation (Similar to the Cache: line in /proc/meminfo on some Linux systems):
# swap -s; swap -l; vmstat 2 2; echo "::memstat" | mdb -k
total: 309376k bytes allocated + 41428k reserved = 350804k used,... (5 Replies)
18:45:47 # free -m
total used free shared buffers cached
Mem: 96679 95909 770 0 1530 19550
-/+ buffers/cache: 74828 21851
Swap: 12287 652 11635
Hi all. The below output is from a RHEL 4.5... (0 Replies)
Right now i am using Red Hat Enterprise Linux AS release 4 and cache memory occupying around 1.5GB mentioned below,
total used free shared buffers cached
Mem: 2026 2021 5 0 161 1477
-/+ buffers/cache: 382 1644 ... (4 Replies)
The environment is Java/Windows. The program keeps near real-time state in memory cache, which is updated by multiple sources, size of the cache is roughly 500 MB, frequency of updates is ~ 20 per second. I am looking into different ways to keep current snapshot of the memory on the disk for a)... (9 Replies)
hi all,
i have noticed that my server has 64 GB RAM and i have application in this server but the server has free memory only 15% and utilized 85% however it didn't eat from swap .
does any parameter can be configured in kernel to make the system clear memory from cache like linux
i found... (4 Replies)
Hi Experts,
Our servers running Solaris 10 with SAP Application. The memory utilization always >90%, but the process on SAP is too less even nothing.
Why memory utilization on solaris always looks high?
I have statement about memory on solaris, is this true:
Memory in solaris is used for... (4 Replies)
i wish to clear memory cache on a production box and i was wondering what is the worst that can happen if i do?
i already tested this on a backup server and everything seemed fine.
but i need to know from you experts what are the worst things that can happen when i run it on a real server:
... (5 Replies)
Hi,
I am new to AIX, Can someone please help me how to know the swap space, total physical memory and system cache?
We are using AIX 5.3.
Thanks! (3 Replies)
#include<stdio.h>
#include<stdlib.h>
#include<sys/time.h>
#include<time.h>
#include "rdtsc.h"
#define SIZE 4*64*1024
int main()
{
unsigned long long a,b;
int arr={0};
int i;
register int r;
a=rdtsc();
r=arr;
b=rdtsc();
printf("1st element Access Cycles = %llu\n",b-a); (2 Replies)
Discussion started by: Vaibhavs1985
2 Replies
LEARN ABOUT SUSE
kcalloc
KCALLOC(9) Memory Management in Linux KCALLOC(9)NAME
kcalloc - allocate memory for an array. The memory is set to zero.
SYNOPSIS
void * kcalloc(size_t n, size_t size, gfp_t flags);
ARGUMENTS
n
number of elements.
size
element size.
flags
the type of memory to allocate.
DESCRIPTION
The flags argument may be one of:
GFP_USER - Allocate memory on behalf of user. May sleep.
GFP_KERNEL - Allocate normal kernel ram. May sleep.
GFP_ATOMIC - Allocation will not sleep. May use emergency pools. For example, use this inside interrupt handlers.
GFP_HIGHUSER - Allocate pages from high memory.
GFP_NOIO - Do not do any I/O at all while trying to get memory.
GFP_NOFS - Do not make any fs calls while trying to get memory.
GFP_NOWAIT - Allocation will not sleep.
GFP_THISNODE - Allocate node-local memory only.
GFP_DMA - Allocation suitable for DMA. Should only be used for kmalloc caches. Otherwise, use a slab created with SLAB_DMA.
Also it is possible to set different flags by OR'ing in one or more of the following additional flags:
__GFP_COLD - Request cache-cold pages instead of trying to return cache-warm pages.
__GFP_HIGH - This allocation has high priority and may use emergency pools.
__GFP_NOFAIL - Indicate that this allocation is in no way allowed to fail (think twice before using).
__GFP_NORETRY - If memory is not immediately available, then give up at once.
__GFP_NOWARN - If allocation fails, don't issue any warnings.
__GFP_REPEAT - If allocation fails initially, try once more before failing.
There are other flags available as well, but these are not intended for general use, and so are not documented here. For a full list of
potential flags, always refer to linux/gfp.h.
COPYRIGHT Kernel Hackers Manual 2.6. July 2010 KCALLOC(9)