filesystem swap

[ASIFKHAN]

how we can create filesystem swap and enable it?plz tell me steps.Though i know how to create device swap creation and enabling.
And how filesystem swap is helpful when we don't have diskspace available for additional device swap?

[Dennis Handly]

Assuming this is HP-UX, (I've asked it to be moved there.) you can just use SAM to do this.

>And how filesystem swap is helpful ..

Well, you can enable it without rebooting and put it on any existing filesystem that has space. But it is slower than device swap, so you want to set the priority so it uses device swap first.

Also, if you have lots of RAM, you should enable pseudo-swap, swapmem_on.

[VK2COT · Accepted solution]

Hello,

If possible, avoid file system swap.
RAM is cheap these days, or set up
multiple device swaps across different disks.

However, if you insist on having
file system swap...

A) From the command-line
(setting priority to 4):

# swapon -p 4 -l 1024M /somefs/myswap1

B) In /etc/fstab:

/dev/vg01/myfs1 /somefs/myswap1 swapfs pri=4,lim=1024M 0 0

Again, I stress out the general swap space
guidelines:

* Avoid file system swap altogether if possible.

* Avoid using busy file systems such as the root file system.

* Avoid using file systems already near capacity.

* Avoid using file systems on disks that already have swap configured.

* Set priorities appropriately.

* Choose faster devices over slower devices.

* Choose infrequently-used file systems over busier file systems.

Cheers,

VK2COT

[palaniappan.sp]

Hi mohd,
In HP-UX,u can able to create to swap in different ways.
1) Device Swap space.(Using entire hdd for swap)
2) Swap File.(Creating a file and use it as a swapfs)
3) Primary and secondary swap.
Primary swap:This swap to be created under / filesystem.
Seciondary swap:This swap to be created any where in the / filesystem after primary swap(i.e. it can be a Swap File).
4) Pseudo swap.

U can configure swap after the installation also.
This link will be useful for u installation and configuration of swap in HP-UX.
http://docs.hp.com/en/B2355-90672/ch06s02.html
Swap will be useful, when ur data processing processes requires more fastest operation(i..e. it will be helpful in feeding the processes when user or a program requires.The data will be in swap under 4 states are wait,run,sleep and zombie.)

If u go through that above link, u will be getting clear i hope...

Note:Try to give points also to everyone then only will come to forward give solution.


Regs
Palani.