Hi,
Would any one be so kind to explain me :
are ulimits defined for each user seperately ? When ?
Specialy what is the impact of :
max locked memory
and
virtual memory
on performance of applications for a user.
Many thanks.
PS :
this is what I can see in MAN :
Last edited by big123456; 08-12-2008 at 05:10 AM..
Hi,
First of all I appreciate this group very much for its informative discussions and posts.
Here is my question.
I have one process whose virtual memory size increases linearly from 6MB to 12MB in 20 minutes. Does that mean my process has memory leaks?
In what cases does the... (4 Replies)
Hi!
I work with HP-UX and I have to monitorize the use of virtual memory for different processes.
(java processes for Tibco Adapter) And if these processes exceed a limit send a message to the syslog.
I donīt know how to monitorize this...
Should I do a script? or use an aplication, for example... (3 Replies)
Hi All,
Does anyone know what the best commands in the UNIX command line are for obtaining this info:
current CPU usage
memory usage
virtual memory usage
preferably with date and time parameters too?
thanks
ocelot (4 Replies)
Hi,
Can anyone please help me workout how much virtual memory I have running on a T2000 running Solaris 10. Thanks
# df -h
swap 3.5G 1.0M 3.5G 1% /etc/svc/volatile
swap 3.5G 208K 3.5G 1% /tmp
swap 3.5G 56K ... (2 Replies)
Is it possible to restrict physical memory in solaris zone with zone.max-locked-memory just like we can do with rcapd ? I do not want to used rcapd (1 Reply)
Hello solaris experts,
Being new to solaris containers, from Linux, feeling difficulty in understanding certain concepts. Hope somebody can help me here.
I understand that, & some questions ....
Locked memory -- memory which will not be swapped out at any cause.
is this for... (0 Replies)
One of our project has exceeded its assigned max-memory-locked by 3 times .. The said project is using around 9 gigs as described by rss parameter in prstat -J .. and the max-project-memory parameter has been defined as 3gigs .. is it normal or we are monitoring the project memory usage in wrong... (2 Replies)
Can anyone tell me what the max num of physical memery depends? It's the bit number of the data bus?
How about the max number of the virtual memory? (1 Reply)
Hi All,
Anyone know how to capture the nmon avg and max cpu and memory for one of the AIX server for Monthly Utilization Report purposes ?
Thanks.
---------- Post updated at 05:18 AM ---------- Previous update was at 05:07 AM ----------
if possible use shell script to count or sum... (6 Replies)
Discussion started by: ckwan
6 Replies
LEARN ABOUT REDHAT
mremap
MREMAP(2) Linux Programmer's Manual MREMAP(2)NAME
mremap - re-map a virtual memory address
SYNOPSIS
#include <unistd.h>
#include <sys/mman.h>
void * mremap(void *old_address, size_t old_size , size_t new_size, unsigned long flags);
DESCRIPTION
mremap expands (or shrinks) an existing memory mapping, potentially moving it at the same time (controlled by the flags argument and the
available virtual address space).
old_address is the old address of the virtual memory block that you want to expand (or shrink). Note that old_address has to be page
aligned. old_size is the old size of the virtual memory block. new_size is the requested size of the virtual memory block after the
resize.
The flags argument is a bitmap of flags.
In Linux the memory is divided into pages. A user process has (one or) several linear virtual memory segments. Each virtual memory seg-
ment has one or more mappings to real memory pages (in the page table). Each virtual memory segment has its own protection (access
rights), which may cause a segmentation violation if the memory is accessed incorrectly (e.g., writing to a read-only segment). Accessing
virtual memory outside of the segments will also cause a segmentation violation.
mremap uses the Linux page table scheme. mremap changes the mapping between virtual addresses and memory pages. This can be used to
implement a very efficient realloc.
FLAGS
MREMAP_MAYMOVE
indicates if the operation should fail, or change the virtual address if the resize cannot be done at the current virtual address.
RETURN VALUE
On success mremap returns a pointer to the new virtual memory area. On error, -1 is returned, and errno is set appropriately.
ERRORS
EINVAL An invalid argument was given. Most likely old_address was not page aligned.
EFAULT "Segmentation fault." Some address in the range old_address to old_address+old_size is an invalid virtual memory address for this
process. You can also get EFAULT even if there exist mappings that cover the whole address space requested, but those mappings are
of different types.
EAGAIN The memory segment is locked and cannot be re-mapped.
ENOMEM The memory area cannot be expanded at the current virtual address, and the MREMAP_MAYMOVE flag is not set in flags. Or, there is
not enough (virtual) memory available.
NOTES
With current glibc includes, in order to get the definition of MREMAP_MAYMOVE, you need to define _GNU_SOURCE before including
<sys/mman.h>.
CONFORMING TO
This call is Linux-specific, and should not be used in programs intended to be portable. 4.2BSD had a (never actually implemented)
mremap(2) call with completely different semantics.
SEE ALSO getpagesize(2), realloc(3), malloc(3), brk(2), sbrk(2), mmap(2)
Your favorite OS text book for more information on paged memory. (Modern Operating Systems by Andrew S. Tannenbaum, Inside Linux by Ran-
dolf Bentson, The Design of the UNIX Operating System by Maurice J. Bach.)
Linux 1.3.87 1996-04-12 MREMAP(2)