Special Forums Hardware About the max num of physical memory Post 302541710 by yazu on Monday 25th of July 2011 11:32:30 AM
It depends on the address bus of a processor. It may have different number of bits from the data bus. (IIRC Pentium IV has 32 and 36 bit buses). The max memory = physical + virtual.
 
Test Your Knowledge in Computers #983
Difficulty: Medium
The first official NetBSD release, NetBSD 0.1, was made on 9 April 1991.
True or False?

10 More Discussions You Might Find Interesting

1. Programming

Physical Memory

Hi, My problem is next.... How can I work with physical memory in the Unix FreeBSD 2.2 or hight? What is the "mem" & "kmem" drivers? P.S./ writing device driver for UNIX FreeBSD 2.2 :D (2 Replies)
Discussion started by: Alex_T
2 Replies

2. UNIX for Dummies Questions & Answers

physical memory

It is just a general question....is there a limit on the memory? I am looking into a process to store image files on the unix server which will be accessed by the application, and I just wonder if there is any limit regarding the physical or virtual memory. I am very new to unix, so thanks for... (1 Reply)
Discussion started by: cchien
1 Replies

3. UNIX for Advanced & Expert Users

vmstat -P (physical memory)

vmstat -P commands gives me an output as shown at the end of this message. my first question is about the difference between "total physical memory" and "total physical memory use" "Total Physical Memory" -"Total Physical Memory Use" 524288 pages-524026 pages= 262 pages does it mean... (0 Replies)
Discussion started by: gfhgfnhhn
0 Replies

4. Solaris

How to check physical memory

HI Please help me how to check the physical memory, model name and hardisk information. (5 Replies)
Discussion started by: jeelans
5 Replies

5. Solaris

physical memory

what is the command to find the physical memory in soalris OS and how to find whether paging is happening or not ? (2 Replies)
Discussion started by: jayaramanit
2 Replies

6. AIX

ulimits max locked memory virtual memory

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 : ulimit ] ... (5 Replies)
Discussion started by: big123456
5 Replies

7. Solaris

How to find Total and Free Physical Memory and Logical Memory in SOLARIS 9

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)
Discussion started by: 0ktalmagik
4 Replies

8. Solaris

restrcit physical memory with zone.max-locked-memory

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)
Discussion started by: fugitive
1 Replies

9. AIX

Physical Memory expansion

IBM says we cannot expand our physical memory on our 570's without upgrading all the existing DIMMS since all slots are currently full. Is it really so difficult for IBM to build servers that leave a couple vacant slots for future expansion? A technical explanation would be greatly appreciated.... (2 Replies)
Discussion started by: 1computerman
2 Replies

10. Solaris

Physical memory calculation

Below is Physical Memory result : -bash-3.00$ prtconf | grep "Memory size" Memory size: 36854 Megabytes -bash-3.00$ vmstat 1 2 | tail -1 0 0 0 28220616 1318888 15 143 0 0 0 0 0 253 2 15 0 5215 14989 5917 7 0 93 and the script i have to calculate this in Percentage is : #!/bin/sh... (3 Replies)
Discussion started by: mjoshi010207
3 Replies
mem(7D) 							      Devices								   mem(7D)

NAME
mem, kmem, allkmem - physical or virtual memory access SYNOPSIS
/dev/mem /dev/kmem /dev/allkmem DESCRIPTION
The file /dev/mem is a special file that provides access to the physical memory of the computer. The file /dev/kmem is a special file that provides access to the virtual address space of the operating system kernel, excluding memory that is associated with an I/O device. The file /dev/allkmem is a special file that provides access to the virtual address space of the operating system kernel, including memory that is associated with an I/O device. You can use any of these devices to examine and modify the system. Byte addresses in /dev/mem are interpreted as physical memory addresses. Byte addresses in /dev/kmem and /dev/allkmem are interpreted as kernel virtual memory addresses. A reference to a non-existent location returns an error. See ERRORS for more information. The file /dev/mem accesses physical memory; the size of the file is equal to the amount of physical memory in the computer. This size may be larger than 4GB on a system running the 32-bit operating environment. In this case, you can access memory beyond 4GB using a series of read(2) and write(2) calls, a pread64() or pwrite64() call, or a combination of llseek(2) and read(2) or write(2). ERRORS
EFAULT Occurs when trying to write(2) a read-only location (allkmem), read(2) a write-only location (allkmem), or read(2) or write(2) a non-existent or unimplemented location (mem, kmem, allkmem). EIO Occurs when trying to read(2) or write(2) a memory location that is associated with an I/O device using the /dev/kmem spe- cial file. ENXIO Results from attempting to mmap(2) a non-existent physical (mem) or virtual (kmem, allkmem) memory address. FILES
/dev/mem Provides access to the computer's physical memory. /dev/kmem Provides access to the virtual address space of the operating system kernel, excluding memory that is associated with an I/O device. /dev/allkmem Provides access to the virtual address space of the operating system kernel, including memory that is associated with an I/O device. SEE ALSO
llseek(2), mmap(2), read(2), write(2) WARNINGS
Using these devices to modify (that is, write to) the address space of a live running operating system or to modify the state of a hardware device is extremely dangerous and may result in a system panic if kernel data structures are damaged or if device state is changed. SunOS 5.10 18 Feb 2002 mem(7D)

Featured Tech Videos

All times are GMT -4. The time now is 06:09 AM.
Unix & Linux Forums Content Copyright 1993-2020. All Rights Reserved.
Privacy Policy