11-29-2013
Well that's a typical example of when a process is suspended for a whole hour waiting for I/O (from the terminal keyboard) which makes it an ideal candidate to be kicked out of RAM when RAM space is tight, and with no need to be swapped back in until you come back, sit down, type something and hit return.
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1. Solaris
Hello and thanks in advance.
I have a Sun box with raid 1 on the O/S disks using solaris svm.
I want to unmirror my swap partition, and add the slice on the second disk as an additional swap device. This would give me twice as much swap space.
I have been warned not to do this by some... (3 Replies)
Discussion started by: BG_JrAdmin
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2. UNIX for Dummies Questions & Answers
ls displays files in tabbed output. Say a directory contains 3 files. ls will list all 3 in one line. So, I expect ls | wc -l to give 1, but it counts the nr of files and gives 3.
Can someone explain how this works? (3 Replies)
Discussion started by: krishmaths
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3. Programming
pls explain me how this works....
DECODE (SUBSTR (field, 1, 1),'''', '''''' || field || '''','''' || field || '''')
here field is a column in an oracle table.... (7 Replies)
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4. UNIX for Dummies Questions & Answers
When I try to execute script, I get message:
>aa.pl
zsh: command not found: aa.pl
but
>./aa.pl
works OK.
What to change in environment to force the former way to work?
Thank you,
Alex Z (4 Replies)
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5. Red Hat
free -m : 1023 total swap space
created default partition /dev/sdb1 50M using fdisk. i did write the changes.
#mkswap /dev/sdb1
#swapon /dev/sdb1
free -m : 1078 total swap space
this shows that the swap is on
Question : i did not change the type LINUX SWAP (82) in fdisk.
so why is... (5 Replies)
Discussion started by: dplinux
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6. HP-UX
Hi
I have an integrity machine rx7620 and rx8640 running hp-ux 11.31. I'm planning to fine tune the system:
- I would like to know when does the memory swap space spill over to the device swap space?
- And how much % of memory swap utilization should be specified (swap space device... (6 Replies)
Discussion started by: lamoul
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7. UNIX for Advanced & Expert Users
I have a program............
#include<stdio.h>
#include<unistd.h>
main()
{
if(fork == 0)
{
printf("Hi every body:p!!!!!!!!!!");
}
}
This program works with out any error. here fork is not a system call. It just act as a variable.But how it works without declaring it? What data type it... (19 Replies)
Discussion started by: carolsanjeevi
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8. Solaris
Hi All,
I want to know how to understand the actual swap size.
My o/p shows as below
root@ecovs1a # swap -s
total: 4546056k bytes allocated + 358856k reserved = 4904912k used, 5046688k available
root@ecovs1a # swap -l
swapfile dev swaplo blocks free
/dev/md/dsk/d31 ... (9 Replies)
Discussion started by: vivek.goel.piet
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9. Solaris
Hi Solaris Folks :),
I need to calculate the swap usage on solaris server, please let me understand the output of below swap -s and swap -l commands.
$swap -s
total: 1774912k bytes allocated + 240616k reserved = 2015528k used, 14542512k available
$swap -l
swapfile dev swaplo... (6 Replies)
Discussion started by: seenuvasan1985
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10. AIX
Please take your time to answer/comment. no urgency. it would help upcoming sysadmins like me in understanding how things work in real time.
OS: AIX
Middleware: Weblogic/WAS
Database: Oracle DB/IBM DB2
Backup s/w tools: not available as of now (except native OS commands/utilities)
I'm a... (5 Replies)
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LEARN ABOUT OPENSOLARIS
bcopy
bcopy(9F) Kernel Functions for Drivers bcopy(9F)
NAME
bcopy - copy data between address locations in the kernel
SYNOPSIS
#include <sys/types.h>
#include <sys/sunddi.h>
void bcopy(const void *from, void *to, size_t bcount);
INTERFACE LEVEL
Architecture independent level 1 (DDI/DKI).
PARAMETERS
from Source address from which the copy is made.
to Destination address to which copy is made.
bcount The number of bytes moved.
DESCRIPTION
The bcopy() function copies bcount bytes from one kernel address to another. If the input and output addresses overlap, the command exe-
cutes, but the results may not be as expected.
Note that bcopy() should never be used to move data in or out of a user buffer, because it has no provision for handling page faults. The
user address space can be swapped out at any time, and bcopy() always assumes that there will be no paging faults. If bcopy() attempts to
access the user buffer when it is swapped out, the system will panic. It is safe to use bcopy() to move data within kernel space, since
kernel space is never swapped out.
CONTEXT
The bcopy() function can be called from user, interrupt, or kernel context.
EXAMPLES
Example 1 Copying data between address locations in the kernel:
An I/O request is made for data stored in a RAM disk. If the I/O operation is a read request, the data is copied from the RAM disk to a
buffer (line 8). If it is a write request, the data is copied from a buffer to the RAM disk (line 15). bcopy() is used since both the RAM
disk and the buffer are part of the kernel address space.
1 #define RAMDNBLK 1000 /* blocks in the RAM disk */
2 #define RAMDBSIZ 512 /* bytes per block */
3 char ramdblks[RAMDNBLK][RAMDBSIZ]; /* blocks forming RAM
/* disk
...
4
5 if (bp->b_flags & B_READ) /* if read request, copy data */
6 /* from RAM disk data block */
7 /* to system buffer */
8 bcopy(&ramdblks[bp->b_blkno][0], bp->b_un.b_addr,
9 bp->b_bcount);
10
11 else /* else write request, */
12 /* copy data from a */
13 /* system buffer to RAM disk */
14 /* data block */
15 bcopy(bp->b_un.b_addr, &ramdblks[bp->b_blkno][0],
16 bp->b_bcount);
SEE ALSO
copyin(9F), copyout(9F)
Writing Device Drivers
WARNINGS
The from and to addresses must be within the kernel space. No range checking is done. If an address outside of the kernel space is
selected, the driver may corrupt the system in an unpredictable way.
SunOS 5.11 16 Jan 2006 bcopy(9F)