06-17-2013
That's right. The operating system tries to avoid this situation by paging (and swapping). But if a process protects too much of it's address space against paging, it sometimes has a really hard time to do so.
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Hello,
The last line of prstat shows load average.
I am unable to figure out what actually it is.
I have read the man pages and also googled, all for no use.
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2. Post Here to Contact Site Administrators and Moderators
Could RSS-support mod be installed for this forum? (3 Replies)
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3. 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.
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4. Solaris
Good Evening everyone,
I am confused about prstat O/P as it shows memory values which are different from actual value.Below is the O/P of prstat command and swap commands.
NPROC USERNAME SIZE RSS MEMORY TIME CPU
48 root 2113M 1590M 1.2% 45:09.39 32%
31 daemon ... (7 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)
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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?
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7. Solaris
Hi,
I have some question about memory in Solaris.
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8. Solaris
Hi everyone,
was hoping someone might be able to help me understand what I am seeing on one of our solaris systems.
prstat -s size -a is showing user oradba as being top virtual memory consumption.
639 oradba 3012G 2951G 100% 59:44:01 25%
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9. Solaris
Hi,
When I sum the RSS number in the ps command for a specific user and compare it with the RSS values of the prstat command of the same user - there is a big difference.
Server details: Solaris 10 5/09 s10s_u7wos_08 SPARC
prstat output:
NPROC USERNAME SWAP RSS MEMORY TIME ... (2 Replies)
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10. 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)
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LEARN ABOUT HPUX
remote_nfs_swap
remote_nfs_swap(5) File Formats Manual remote_nfs_swap(5)
NAME
remote_nfs_swap - enable swapping across NFS
VALUES
Default
Allowed values
DESCRIPTION
This tunable controls adding a NFS filesystem for use as swap. If is set to only local filesystems and devices can be used for swap. If
it is set to both local and networked file systems can be used for swap.
Historically, this tunable was used in NFS clusters that are no longer supported, but this capability has not yet been removed.
Who Is Expected to Change This Tunable?
Anyone.
Restrictions on Changing
Changes to this tunable take effect on the next boot.
When Should the Tunable Be Turned On?
Almost never. As previously mentioned, this tunable was designed for systems which are not in use today. Only systems with extremely
robust NFS capabilities should even consider using NFS for swap.
What Are the Side Effects of Turning the Tunable On?
If the value is set to and a NFS partition is added as swap, then some kernel memory will be set aside for NFS transactions to the swap
file system. The kernel will then use the NFS swap partition just the same as a local file system. If the NFS capabilities of the system
are not robust, this could lead to extremely long swap times (both swap in and swap out), and possibly a loss of memory because all the
reserved memory and more could be used by NFS (just when memory pressure is high) causing the need for swap.
When Should the Tunable Be Turned Off?
Unless you are positive that the NFS system can handle the load of being used as swap, and does not have a local file system or disk drive
to spare, this tunable should be set to
What Are the Side Effects of Turning the Tunable Off?
Any previously defined NFS swap filesystems will no longer be allowed. Kernel memory will not be reserved for NFS transactions due to
swap.
What Other Tunables Should Be Changed at the Same Time?
None.
WARNINGS
All HP-UX kernel tunable parameters are release specific. This parameter may be removed or have its meaning changed in future releases of
HP-UX.
Installation of optional kernel software, from HP or other vendors, may cause changes to tunable parameter values. After installation,
some tunable parameters may no longer be at the default or recommended values. For information about the effects of installation on tun-
able values, consult the documentation for the kernel software being installed. For information about optional kernel software that was
factory installed on your system, see at
AUTHOR
was developed by HP.
Tunable Kernel Parameters remote_nfs_swap(5)