Pagefile almost = hiberfile in size??

I happened to notice this:

My pagefile is 3,219,111,936 bytes
My hiberfile is 3,219,181,568 bytes

Is this a coincidence, or is there a relationship?

IIUC, the size of the hiberfile is the amount of RAM being used the last
time the computer was hibernated.

And the size of the pagefile is dependant on how much extra RAM would be
needed if there were no such thing as virtual memory.

Right?

At most the hiberfile will be 4Gig, since that's all the memory I have.
In practice it will be close to 4G.

I don't know what the limit is on the size of the pagefile.

There doesn't seem any reason why the numbers would be so close
together. Is that true? Is it a coincidence that they numbers are so
close together?

(I could wait and compare again later, but I hibernate now only every
few weeks and I don't know how often the size of the pagefile changes.

On 26/06/2015 22:47, micky wrote:
I happened to notice this:

My pagefile is 3,219,111,936 bytes
My hiberfile is 3,219,181,568 bytes

Is this a coincidence, or is there a relationship?

IIUC, the size of the hiberfile is the amount of RAM being used the last
time the computer was hibernated.

And the size of the pagefile is dependant on how much extra RAM would be
needed if there were no such thing as virtual memory.

Right?

At most the hiberfile will be 4Gig, since that's all the memory I have.
In practice it will be close to 4G.

I don't know what the limit is on the size of the pagefile.

There doesn't seem any reason why the numbers would be so close
together. Is that true? Is it a coincidence that they numbers are so
close together?

(I could wait and compare again later, but I hibernate now only every
few weeks and I don't know how often the size of the pagefile changes.


Pagefile is something you can control yourself from Control Panel but
some people don't bother with it so Windows creates a default (about 10%
of HD size).

Hiberfile is for hibernation and the size depends on what programs are
running at any one particular time.

You can check whether there is any connection between the two by going
into safe mode and deleting them. Then restart your machine and both
files will be recreated. If you are scarred of deleting anything, you
can rename them and then when they are recreated, delete the old files
or save them on an external HD as souvenir.

micky wrote on 6/26/2015 3:47 PM:
I happened to notice this:

My pagefile is 3,219,111,936 bytes
My hiberfile is 3,219,181,568 bytes

Is this a coincidence, or is there a relationship?

IIUC, the size of the hiberfile is the amount of RAM being used the last
time the computer was hibernated.

And the size of the pagefile is dependant on how much extra RAM would be
needed if there were no such thing as virtual memory.

Right?

At most the hiberfile will be 4Gig, since that's all the memory I have.
In practice it will be close to 4G.

I don't know what the limit is on the size of the pagefile.

There doesn't seem any reason why the numbers would be so close
together. Is that true? Is it a coincidence that they numbers are so
close together?

(I could wait and compare again later, but I hibernate now only every
few weeks and I don't know how often the size of the pagefile changes.

I'm more interest why the sizes are different than why they are close.
The XP default is to set the size of the page file to that of memory.
When hibernation is enabled, the file must be as large as memory (if all
memory is in use) so that everything can be saved. And that is the XP
default size. These numbers can be influenced by memory and/or address
space being shared with or mapped onto devices. I also believe XP might
start the paging file smaller and grow it as necessary.

Win 7 has changed these default behaviors as best I can tell: Since
memory on most any modern machine can be as large as 64GB and larger on
some machines, this can waste a lot of disk space. The wasted space is
miniscule if you have a 2TB disk or larger but think of the hit on an
SSD of 128-256GB. I have a very large memory and a medium sized SSD. The
first thing I did, in Win 7, is move the page file to a non SSD disk - I
don't think my machine will every page because of its large memory but
the cost for a piece of a 4TB is small.

Hibernation for my computer, a desktop, is necessary to support UPS
software; it hibernates the machine in case of power failure. However,
Win 7 only allocated a hiberfile.sys that is about 75% of my memory
size. The OS has some sort of algorithm which guesses how much to wack
off as a function of memory size. I think it is 100% of memory size for
relatively small memories and any 32-bit system. N.B. You can not
relocate hiberfile.sys to another disk. It turns out that there is a
protocol between motherboard and OS that rigidly defines where parts of
the hibernation file must be.
--
Jeff Barnett