10 More Discussions You Might Find Interesting
1. UNIX for Beginners Questions & Answers
So, I would ask you a piece of advice about which books or titles could give me comprehensive information about virtual memory in UNIX. Especially, I would found out that virtual address translation corresponds structures of kernel!
Thanks! (2 Replies)
Discussion started by: Fadedfate
2 Replies
2. AIX
Hi
I am running AIX 5.2. My server is running low on memory. It it using about 1307775 file pages on a total of 1511424 (from vmstat -v).
I looked at the memory yesterday morning, and we had plenty of free memory. I did a backup from Windows (ftp mget command) of a large file selection. From... (5 Replies)
Discussion started by: fredrivard
5 Replies
3. HP-UX
Hello! just wanna ask if how UNIX implements virtual memory, and how it handles page faults, working sets, page sizes and how it reconciles thrashing issues? if you know some sources where I can have some idea, just post it here. thx (1 Reply)
Discussion started by: kjcruz
1 Replies
4. UNIX for Dummies Questions & Answers
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)
Discussion started by: jamba1
2 Replies
5. UNIX for Dummies Questions & Answers
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)
Discussion started by: ocelot
4 Replies
6. AIX
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. HP-UX
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)
Discussion started by: Kurohana
3 Replies
8. Programming
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)
Discussion started by: shriashishpatil
4 Replies
9. UNIX for Dummies Questions & Answers
Hi,
can anyone explain me what virtual memory is ( for which we use vmstat commande line ) comparing with RAM ?
many thanks before. (2 Replies)
Discussion started by: big123456
2 Replies
10. Shell Programming and Scripting
HP UNIX version 10.20
I have been using system variable names in some shell scripts in order to automate execution of some test software. I have recently found that there appears to be a restriction with the 'ls' command when listing specific files (e.g. ls *.c). If I pipe the output into wc, I... (5 Replies)
Discussion started by: degwright
5 Replies
svatophys(9r) svatophys(9r)
NAME
svatophys - General: Converts a system virtual address to a physical address
SYNOPSIS
kern_return_t svatophys(
vm_offset_t kern_addr,
vm_offset_t *phys_addr );
ARGUMENTS
Specifies the kernel virtual address. Specifies a pointer to the physical address to be filled in.
DESCRIPTION
The svatophys routine converts a system virtual address to the corresponding physical address. All address and data structure manipulation
done within the kernel is performed using system virtual addresses. Typically, system virtual addresses are a means of mapping physical
memory and I/O space, which often consists of device registers and DMA buffers. In contrast to this, devices are usually unaware of any
virtual addressing and for this reason use physical addresses. You use the svatophys routine to perform this address translation.
As an example of where you can use this address translation, a disk device driver can use DMA buffers to transfer blocks of data to the
disk (for the case of a write operation). The data to be written to disk is present in system memory at a system virtual address known to
the driver. To initiate the DMA operation, the disk driver can set up a command packet to specify a write operation to the underlying disk
controller hardware. This write command packet contains (among other things) the location of the DMA buffer as a physical address and the
length of the buffer. Here, the driver calls the svatophys routine to translate the system virtual address of the DMA buffer to a physical
address in the command packet issued to the disk driver.
RETURN VALUES
The svatophys routine returns the following: The address translation has been completed successfully. Unable to perform address transla-
tion. This value indicates that the address specified by the kern_addr argument is not a valid kernel or system virtual address.
svatophys(9r)