Re: few questions on the hd6 paging


Laurenz Albe wrote:
pui ming Wong <s11976@xxxxxxxxxxxxxxxx> wrote:
When I migrated aix 4.3.3 from an old box to a new
one, somehow i had to keep the primary hd6 (which was
quite small)
My new box had 1Gb
My hd6 was only 352Mb
So I added an extra paging00 (say 1728Mb)

Questions:
Can I delete the hd6 and so add a single paging space say 2048 Mb in rootvg

You cannot easily delete hd6, as it is hard coded into the startup scripts.
You can change those and bosboot, but I'd advise against it.

If You want a single big paging space in rootvg, the correct solution is
to remove paging00 and extend hd6 to the desired size.

Or
If I cannot, is there any difference in performance to create
the extra paging00 on a vg other than rootvg (since that vg resides
on a separate disk which would distribute the i/o better ?
Is this not too significant ?

I think that it is not a smart idea to have a paging space outside rootvg.
The advantage of multiple volume groups is to keep the operating system and
various other data cleanly separated, with the option to easily relocate
the latter from one machine to the other by exporting and importing the
volume group.
By having a paging space (that is activated on bootup) you break that
concept.

I think that you should have only one paging space per 'mirror group' in
rootvg.

Paging I/O speed is maybe less important than it seems - if your machine
pages enough that paging space performance becomes a problem, your setup
is wrong anyway, and your performance will be very bad even if paging space
I/O is optimized.

Yours,
Laurenz Albe

but disk is cheap and memory is expensive... if you are limited to not
buying more memory, then spreading paging space over as many disks as
possible will certainly be helpful.

.

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  • Re: few questions on the hd6 paging
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  • Re: few questions on the hd6 paging
    ... My hd6 was only 352Mb ... Can I delete the hd6 and so add a single paging space say 2048 Mb in rootvg ... Paging I/O speed is maybe less important than it seems - if your machine ...
    (comp.unix.aix)
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