* VM Vs Swap space
@ 2004-10-06 8:52 Ankit Jain
2004-10-07 1:57 ` chuck gelm
0 siblings, 1 reply; 17+ messages in thread
From: Ankit Jain @ 2004-10-06 8:52 UTC (permalink / raw)
To: newbie
hi
if somebody can tell me that is this correct?
can i say that swap area created by linux is nothign
but virtual memory. is it correct to use the term
interchangeably
thanks
ankit
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^ permalink raw reply [flat|nested] 17+ messages in thread
* Re: VM Vs Swap space
2004-10-06 8:52 VM Vs Swap space Ankit Jain
@ 2004-10-07 1:57 ` chuck gelm
2004-10-07 6:01 ` kernel kernel
2004-10-07 9:15 ` Ankit Jain
0 siblings, 2 replies; 17+ messages in thread
From: chuck gelm @ 2004-10-07 1:57 UTC (permalink / raw)
To: Ankit Jain; +Cc: newbie
Ankit Jain wrote:
>hi
>
>if somebody can tell me that is this correct?
>
>(1)can i say that swap area created by linux is nothign
>but virtual memory. (2)is it correct to use the term
>interchangeably
>
>thanks
>
>ankit
>
>
(1) A swap file or swap partition can be used as virtual memory.
(2) I am not sure. Why one would wish to use 'swap area'
interchangeably with 'virtual memory'.
:-|
Chuck
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^ permalink raw reply [flat|nested] 17+ messages in thread
* Re: VM Vs Swap space
2004-10-07 1:57 ` chuck gelm
@ 2004-10-07 6:01 ` kernel kernel
2004-10-07 9:15 ` Ankit Jain
1 sibling, 0 replies; 17+ messages in thread
From: kernel kernel @ 2004-10-07 6:01 UTC (permalink / raw)
To: chuck; +Cc: Ankit Jain, newbie
swap area forms a part of the memory which is used for the memory
objects like the stack when executable
starts running. This anonymous segment will grow dependin upon the
pattern of the functions calls in ur executable
On Wed, 06 Oct 2004 21:57:27 -0400, chuck gelm <chuck@gelm.net> wrote:
> Ankit Jain wrote:
>
> >hi
> >
> >if somebody can tell me that is this correct?
> >
> >(1)can i say that swap area created by linux is nothign
> >but virtual memory. (2)is it correct to use the term
> >interchangeably
> >
> >thanks
> >
> >ankit
> >
> >
> (1) A swap file or swap partition can be used as virtual memory.
> (2) I am not sure. Why one would wish to use 'swap area'
> interchangeably with 'virtual memory'.
> :-|
> Chuck
>
>
>
>
> -
> To unsubscribe from this list: send the line "unsubscribe linux-newbie" in
> the body of a message to majordomo@vger.kernel.org
> More majordomo info at http://vger.kernel.org/majordomo-info.html
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>
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^ permalink raw reply [flat|nested] 17+ messages in thread
* Re: VM Vs Swap space
2004-10-07 1:57 ` chuck gelm
2004-10-07 6:01 ` kernel kernel
@ 2004-10-07 9:15 ` Ankit Jain
2004-10-07 9:25 ` kernel kernel
2004-10-07 10:41 ` chuck gelm
1 sibling, 2 replies; 17+ messages in thread
From: Ankit Jain @ 2004-10-07 9:15 UTC (permalink / raw)
To: chuck; +Cc: newbie
how will u differentiate virtual memory and swap area
thanks
ankit
--- chuck gelm <chuck@gelm.net> wrote:
> Ankit Jain wrote:
>
> >hi
> >
> >if somebody can tell me that is this correct?
> >
> >(1)can i say that swap area created by linux is
> nothign
> >but virtual memory. (2)is it correct to use the
> term
> >interchangeably
> >
> >thanks
> >
> >ankit
> >
> >
> (1) A swap file or swap partition can be used as
> virtual memory.
> (2) I am not sure. Why one would wish to use 'swap
> area'
> interchangeably with 'virtual memory'.
> :-|
> Chuck
>
>
>
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^ permalink raw reply [flat|nested] 17+ messages in thread
* Re: VM Vs Swap space
2004-10-07 9:15 ` Ankit Jain
@ 2004-10-07 9:25 ` kernel kernel
2004-10-07 9:37 ` Ankit Jain
2004-10-07 10:41 ` chuck gelm
1 sibling, 1 reply; 17+ messages in thread
From: kernel kernel @ 2004-10-07 9:25 UTC (permalink / raw)
To: Ankit Jain; +Cc: chuck, newbie
Virtual Memory is a policy. Swap Area is a artifact, u use to
implement this policy
Hope makes sense
On Thu, 7 Oct 2004 10:15:15 +0100 (BST), Ankit Jain
<ankitjain1580@yahoo.com> wrote:
> how will u differentiate virtual memory and swap area
>
> thanks
>
> ankit
> --- chuck gelm <chuck@gelm.net> wrote:
> > Ankit Jain wrote:
> >
> > >hi
> > >
> > >if somebody can tell me that is this correct?
> > >
> > >(1)can i say that swap area created by linux is
> > nothign
> > >but virtual memory. (2)is it correct to use the
> > term
> > >interchangeably
> > >
> > >thanks
> > >
> > >ankit
> > >
> > >
> > (1) A swap file or swap partition can be used as
> > virtual memory.
> > (2) I am not sure. Why one would wish to use 'swap
> > area'
> > interchangeably with 'virtual memory'.
> > :-|
> > Chuck
> >
> >
> >
>
> ________________________________________________________________________
> Yahoo! Messenger - Communicate instantly..."Ping"
> your friends today! Download Messenger Now
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>
>
> -
> To unsubscribe from this list: send the line "unsubscribe linux-newbie" in
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^ permalink raw reply [flat|nested] 17+ messages in thread
* Re: VM Vs Swap space
2004-10-07 9:25 ` kernel kernel
@ 2004-10-07 9:37 ` Ankit Jain
2004-10-07 10:31 ` chuck gelm
` (2 more replies)
0 siblings, 3 replies; 17+ messages in thread
From: Ankit Jain @ 2004-10-07 9:37 UTC (permalink / raw)
To: kernel kernel; +Cc: newbie
well if we dont have a swap area then shall i say my
system dosent have virtual memory
is this correct? because i feel even if this swap area
is not there then also virtual memory concept exists?
thanks
ankit
--- kernel kernel <unix.hacker@gmail.com> wrote:
> Virtual Memory is a policy. Swap Area is a
> artifact, u use to
> implement this policy
>
> Hope makes sense
>
>
> On Thu, 7 Oct 2004 10:15:15 +0100 (BST), Ankit Jain
> <ankitjain1580@yahoo.com> wrote:
> > how will u differentiate virtual memory and swap
> area
> >
> > thanks
> >
> > ankit
> > --- chuck gelm <chuck@gelm.net> wrote:
> > > Ankit Jain wrote:
> > >
> > > >hi
> > > >
> > > >if somebody can tell me that is this correct?
> > > >
> > > >(1)can i say that swap area created by linux is
> > > nothign
> > > >but virtual memory. (2)is it correct to use the
> > > term
> > > >interchangeably
> > > >
> > > >thanks
> > > >
> > > >ankit
> > > >
> > > >
> > > (1) A swap file or swap partition can be used as
> > > virtual memory.
> > > (2) I am not sure. Why one would wish to use
> 'swap
> > > area'
> > > interchangeably with 'virtual memory'.
> > > :-|
> > > Chuck
> > >
> > >
> > >
> >
> >
>
________________________________________________________________________
> > Yahoo! Messenger - Communicate instantly..."Ping"
> > your friends today! Download Messenger Now
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> >
> >
> > -
> > To unsubscribe from this list: send the line
> "unsubscribe linux-newbie" in
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> > More majordomo info at
> http://vger.kernel.org/majordomo-info.html
> > Please read the FAQ at
> http://www.linux-learn.org/faqs
> >
>
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^ permalink raw reply [flat|nested] 17+ messages in thread
* Re: VM Vs Swap space
2004-10-07 9:37 ` Ankit Jain
@ 2004-10-07 10:31 ` chuck gelm
2004-10-07 16:05 ` Pratik Solanki
2004-10-07 16:07 ` Pratik Solanki
2 siblings, 0 replies; 17+ messages in thread
From: chuck gelm @ 2004-10-07 10:31 UTC (permalink / raw)
To: Ankit Jain; +Cc: kernel kernel, newbie
Ankit Jain wrote:
>well if we dont have a swap area then shall i say my
>system dosent have virtual memory
>
>
Yes, I think so. I think that it is difficult to say that a system
has no 'swap area', because a 'swap area' could be a file.
How can you be sure that none of the files on a system are
a 'swap file' ?
I think that you can say that a system has no 'swap' or 'virtual memory'
if there are no swap areas enabled.
I suggest that the output of 'free' will indicate your swap.
If 'free' indicates that you have no swap, then you have no swap.
If 'free' indicates that you have swap, then you have swap.
>is this correct? because i feel even if this swap area
>is not there then also virtual memory concept exists?
>
A system can have a swap partition and not use it.
A system can have a swap file and not use it.
Swap can be enabled and disabled on a running kernel.
So, at any given instance, a running system can have
or have not 'virtual memory'.
>thanks
>
>ankit
>--- kernel kernel <unix.hacker@gmail.com> wrote:
>
>
>>Virtual Memory is a policy. Swap Area is a
>>artifact, u use to
>>implement this policy
>>
>>Hope makes sense
>>
>>
>>On Thu, 7 Oct 2004 10:15:15 +0100 (BST), Ankit Jain
>><ankitjain1580@yahoo.com> wrote:
>>
>>
>>>how will u differentiate virtual memory and swap
>>>
>>>
>>area
>>
>>
>>>thanks
>>>
>>>ankit
>>>--- chuck gelm <chuck@gelm.net> wrote:
>>>
>>>
>>>>Ankit Jain wrote:
>>>>
>>>>
>>>>
>>>>>hi
>>>>>
>>>>>if somebody can tell me that is this correct?
>>>>>
>>>>>(1)can i say that swap area created by linux is
>>>>>
>>>>>
>>>>nothign
>>>>
>>>>
>>>>>but virtual memory. (2)is it correct to use the
>>>>>
>>>>>
>>>>term
>>>>
>>>>
>>>>>interchangeably
>>>>>
>>>>>thanks
>>>>>
>>>>>ankit
>>>>>
>>>>>
>>>>>
>>>>>
>>>>(1) A swap file or swap partition can be used as
>>>>virtual memory.
>>>>(2) I am not sure. Why one would wish to use
>>>>
>>>>
>>'swap
>>
>>
>>>>area'
>>>>interchangeably with 'virtual memory'.
>>>>:-|
>>>>Chuck
>>>>
>>>>
-
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^ permalink raw reply [flat|nested] 17+ messages in thread
* Re: VM Vs Swap space
2004-10-07 9:15 ` Ankit Jain
2004-10-07 9:25 ` kernel kernel
@ 2004-10-07 10:41 ` chuck gelm
2004-10-07 16:09 ` Pratik Solanki
1 sibling, 1 reply; 17+ messages in thread
From: chuck gelm @ 2004-10-07 10:41 UTC (permalink / raw)
To: Ankit Jain; +Cc: newbie
Ankit Jain wrote:
>how will u differentiate virtual memory and swap area
>
>thanks
>
>ankit
>
>
Virtual memory is swap area in use.
Regards, Chuck
> --- chuck gelm <chuck@gelm.net> wrote:
>
>
>>Ankit Jain wrote:
>>
>>
>>
>>>hi
>>>
>>>if somebody can tell me that is this correct?
>>>
>>>(1)can i say that swap area created by linux is
>>>
>>>
>>nothign
>>
>>
>>>but virtual memory. (2)is it correct to use the
>>>
>>>
>>term
>>
>>
>>>interchangeably
>>>
>>>thanks
>>>
>>>ankit
>>>
>>>
>>>
>>>
>>(1) A swap file or swap partition can be used as
>>virtual memory.
>>(2) I am not sure. Why one would wish to use 'swap
>>area'
>>interchangeably with 'virtual memory'.
>>:-|
>>Chuck
>>
>>
-
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^ permalink raw reply [flat|nested] 17+ messages in thread
* Re: VM Vs Swap space
2004-10-07 9:37 ` Ankit Jain
2004-10-07 10:31 ` chuck gelm
@ 2004-10-07 16:05 ` Pratik Solanki
2004-10-07 16:07 ` Pratik Solanki
2 siblings, 0 replies; 17+ messages in thread
From: Pratik Solanki @ 2004-10-07 16:05 UTC (permalink / raw)
To: linux-newbie
On Thu, 7 Oct 2004 10:37:40 +0100 (BST), Ankit Jain
<ankitjain1580@yahoo.com> wrote:
> well if we dont have a swap area then shall i say my
> system dosent have virtual memory
No.
> is this correct? because i feel even if this swap area
> is not there then also virtual memory concept exists?
Virtual memory is the reason why applications can think they have 4GB
of memory while your physical machine might actually have only 32MB.
You don't need to have swap in order to have virtual memory, although
its very advantageous to have swap with VM.
Virtual memory maps the viurtual pages (from 0 to 4GB) to actually
physical memory pages (from 0 to however much RAM you have). Swapping
is the process of using the disk to store physical memory pages when
they are not in use, and then restoring them when an application
accesses them.
-
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^ permalink raw reply [flat|nested] 17+ messages in thread
* Re: VM Vs Swap space
2004-10-07 9:37 ` Ankit Jain
2004-10-07 10:31 ` chuck gelm
2004-10-07 16:05 ` Pratik Solanki
@ 2004-10-07 16:07 ` Pratik Solanki
2004-10-08 3:29 ` kernel kernel
2 siblings, 1 reply; 17+ messages in thread
From: Pratik Solanki @ 2004-10-07 16:07 UTC (permalink / raw)
To: linux-newbie
On Thu, 7 Oct 2004 10:37:40 +0100 (BST), Ankit Jain
<ankitjain1580@yahoo.com> wrote:
> well if we dont have a swap area then shall i say my
> system dosent have virtual memory
No.
> is this correct? because i feel even if this swap area
> is not there then also virtual memory concept exists?
Virtual memory is the reason why applications can think they have 4GB
of memory while your physical machine might actually have only 32MB.
You don't need to have swap in order to have virtual memory, although
its very advantageous to have swap with VM.
Virtual memory maps the viurtual pages (from 0 to 4GB) to actually
physical memory pages (from 0 to however much RAM you have). Swapping
is the process of using the disk to store physical memory pages when
they are not in use, and then restoring them when an application
accesses them.
Pratik.
-
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^ permalink raw reply [flat|nested] 17+ messages in thread
* Re: VM Vs Swap space
2004-10-07 10:41 ` chuck gelm
@ 2004-10-07 16:09 ` Pratik Solanki
[not found] ` <20041007172157.63553.qmail@web52908.mail.yahoo.com>
0 siblings, 1 reply; 17+ messages in thread
From: Pratik Solanki @ 2004-10-07 16:09 UTC (permalink / raw)
To: linux-newbie
On Thu, 07 Oct 2004 06:41:38 -0400, chuck gelm <chuck@gelm.net> wrote:
> Ankit Jain wrote:
>
> >how will u differentiate virtual memory and swap area
> >
> >thanks
> >
> >ankit
> >
> >
> Virtual memory is swap area in use.
umm. A running system can or cannot have swap. Correct me if I am
wrong but you can't disable virtual memory once its enabled, or at the
very least it would be extremely tough to do so and I don't know of
any system that does it. Virtual memory is enabled when the kernel
starts up and stays that way. Swap is a different issue.
Pratik.
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^ permalink raw reply [flat|nested] 17+ messages in thread
* Re: VM Vs Swap space
[not found] ` <20041007160656.32450.qmail@web52904.mail.yahoo.com>
@ 2004-10-07 16:13 ` Pratik Solanki
0 siblings, 0 replies; 17+ messages in thread
From: Pratik Solanki @ 2004-10-07 16:13 UTC (permalink / raw)
To: Ankit Jain; +Cc: linux-newbie
Yes. 32 bit address = 2^32 addresses = 4GB
For a 64-bit machine, the limit is 2^64.
Pratik.
On Thu, 7 Oct 2004 17:06:56 +0100 (BST), Ankit Jain
<ankitjain1580@yahoo.com> wrote:
> why limit is upto 4 GB is it due to address bus limit?
>
> thanks
>
> ankit
> --- Pratik Solanki <pratik.solanki.ml@gmail.com>
> wrote:
>
>
> > On Thu, 7 Oct 2004 10:37:40 +0100 (BST), Ankit Jain
> > <ankitjain1580@yahoo.com> wrote:
> > > well if we dont have a swap area then shall i say
> > my
> > > system dosent have virtual memory
> >
> > No.
> >
> > > is this correct? because i feel even if this swap
> > area
> > > is not there then also virtual memory concept
> > exists?
> >
> > Virtual memory is the reason why applications can
> > think they have 4GB
> > of memory while your physical machine might actually
> > have only 32MB.
> > You don't need to have swap in order to have virtual
> > memory, although
> > its very advantageous to have swap with VM.
> >
> > Virtual memory maps the viurtual pages (from 0 to
> > 4GB) to actually
> > physical memory pages (from 0 to however much RAM
> > you have). Swapping
> > is the process of using the disk to store physical
> > memory pages when
> > they are not in use, and then restoring them when an
> > application
> > accesses them.
> >
> > Pratik.
> >
>
> ________________________________________________________________________
> Yahoo! Messenger - Communicate instantly..."Ping"
> your friends today! Download Messenger Now
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^ permalink raw reply [flat|nested] 17+ messages in thread
* Re: VM Vs Swap space
[not found] ` <20041007172157.63553.qmail@web52908.mail.yahoo.com>
@ 2004-10-07 18:49 ` Pratik Solanki
2004-10-07 22:13 ` chuck gelm
0 siblings, 1 reply; 17+ messages in thread
From: Pratik Solanki @ 2004-10-07 18:49 UTC (permalink / raw)
To: Ankit Jain; +Cc: linux-newbie
[CCing linux-newbie]
On Thu, 7 Oct 2004 18:21:57 +0100 (BST), Ankit Jain
<ankitjain1580@yahoo.com> wrote:
> well i dont know exactly but somewhat i feel that
> there must be some way to disable the virtual memory.
> yaa of course there should be some way. it is not that
> sys cant work without it
Yes, you can have a system without virtual memory. Search for MMUless
linux kernel and you'll see patches/websites.
My point was that disabling VM after its been enabled would tough (if
not impossible). Someone correct me if I am wrong here.
Pratik.
> ankit
> --- Pratik Solanki <pratik.solanki.ml@gmail.com>
> wrote:
>
>
> > On Thu, 07 Oct 2004 06:41:38 -0400, chuck gelm
> > <chuck@gelm.net> wrote:
> > > Ankit Jain wrote:
> > >
> > > >how will u differentiate virtual memory and swap
> > area
> > > >
> > > >thanks
> > > >
> > > >ankit
> > > >
> > > >
> > > Virtual memory is swap area in use.
> >
> > umm. A running system can or cannot have swap.
> > Correct me if I am
> > wrong but you can't disable virtual memory once its
> > enabled, or at the
> > very least it would be extremely tough to do so and
> > I don't know of
> > any system that does it. Virtual memory is enabled
> > when the kernel
> > starts up and stays that way. Swap is a different
> > issue.
> >
> > Pratik.
> > -
> > To unsubscribe from this list: send the line
> > "unsubscribe linux-newbie" in
> > the body of a message to majordomo@vger.kernel.org
> > More majordomo info at
> > http://vger.kernel.org/majordomo-info.html
> > Please read the FAQ at
> > http://www.linux-learn.org/faqs
>
>
> >
>
> ________________________________________________________________________
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^ permalink raw reply [flat|nested] 17+ messages in thread
* Re: VM Vs Swap space
2004-10-07 18:49 ` Pratik Solanki
@ 2004-10-07 22:13 ` chuck gelm
2004-10-08 2:49 ` Jim Nelson
2004-10-08 15:25 ` Pratik Solanki
0 siblings, 2 replies; 17+ messages in thread
From: chuck gelm @ 2004-10-07 22:13 UTC (permalink / raw)
To: Pratik Solanki; +Cc: Ankit Jain, linux-newbie
Pratik Solanki wrote:
>[CCing linux-newbie]
>
>On Thu, 7 Oct 2004 18:21:57 +0100 (BST), Ankit Jain
><ankitjain1580@yahoo.com> wrote:
>
>
>>well i dont know exactly but somewhat i feel that
>>there must be some way to disable the virtual memory.
>>yaa of course there should be some way. it is not that
>>sys cant work without it
>>
>>
>
>Yes, you can have a system without virtual memory. Search for MMUless
>linux kernel and you'll see patches/websites.
>
>My point was that disabling VM after its been enabled would tough (if
>not impossible). Someone correct me if I am wrong here.
>
>Pratik.
>
I was thinking that an active swap partition was 'virtual memory'.
Why are many folks using capital letters 'VM'. Am I missing
something? Is 'VM' == virtual memory or is there a application
or service called 'VM' ?
Anywho, the only 'virtual memory' I know of is an active
swap file or swap partition and either can be started
or stopped in a running kernel.
(I think.)
Regards, Chuck
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^ permalink raw reply [flat|nested] 17+ messages in thread
* Re: VM Vs Swap space
2004-10-07 22:13 ` chuck gelm
@ 2004-10-08 2:49 ` Jim Nelson
2004-10-08 15:25 ` Pratik Solanki
1 sibling, 0 replies; 17+ messages in thread
From: Jim Nelson @ 2004-10-08 2:49 UTC (permalink / raw)
To: chuck; +Cc: Pratik Solanki, Ankit Jain, linux-newbie
chuck gelm wrote:
> Pratik Solanki wrote:
>
>> [CCing linux-newbie]
>>
>> On Thu, 7 Oct 2004 18:21:57 +0100 (BST), Ankit Jain
>> <ankitjain1580@yahoo.com> wrote:
>>
>>
>>> well i dont know exactly but somewhat i feel that
>>> there must be some way to disable the virtual memory.
>>> yaa of course there should be some way. it is not that
>>> sys cant work without it
>>>
>>
>>
>> Yes, you can have a system without virtual memory. Search for MMUless
>> linux kernel and you'll see patches/websites.
>>
>> My point was that disabling VM after its been enabled would tough (if
>> not impossible). Someone correct me if I am wrong here.
>>
>> Pratik.
>>
> I was thinking that an active swap partition was 'virtual memory'.
> Why are many folks using capital letters 'VM'. Am I missing
> something? Is 'VM' == virtual memory or is there a application
> or service called 'VM' ?
>
> Anywho, the only 'virtual memory' I know of is an active
> swap file or swap partition and either can be started
> or stopped in a running kernel.
> (I think.)
>
> Regards, Chuck
From "Understanding the Linux Kernel":
"Virtual memory acts as a logical layer between the application memory
requests and the hardware Memory Management Unit (MMU)."
It is an abstraction of system memory to provide an
architecture-independent memory interface. It allows for a great many
things, including swap functionality, but its primary function is to
make the details of memory management invisible to application
programmers. You just malloc() some memory, and you don't have to worry
overmuch about far jumps, hardware cache alignment, or other annoying stuff.
It also allows large malloc() calls to succeed, even if physical memory
is completely fragmented, by maintaining a set of page tables that allow
virtual-to-physical mapping of memory addresses.
This is one of the most challenging areas of kernel development, and
very hardware-specific. I tried to understand how it worked recently,
gave myself a splitting headache after 30 minutes, and decided to let it
sit for another year or so until I understand kernel internals, computer
architecture, and assembler much better than I do now :)
Jim
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^ permalink raw reply [flat|nested] 17+ messages in thread
* Re: VM Vs Swap space
2004-10-07 16:07 ` Pratik Solanki
@ 2004-10-08 3:29 ` kernel kernel
0 siblings, 0 replies; 17+ messages in thread
From: kernel kernel @ 2004-10-08 3:29 UTC (permalink / raw)
To: Pratik Solanki; +Cc: linux-newbie
In That case, also. There is a implicit Swap area and a Explicit area.
On Thu, 7 Oct 2004 12:07:21 -0400, Pratik Solanki
<pratik.solanki.ml@gmail.com> wrote:
> On Thu, 7 Oct 2004 10:37:40 +0100 (BST), Ankit Jain
> <ankitjain1580@yahoo.com> wrote:
> > well if we dont have a swap area then shall i say my
> > system dosent have virtual memory
>
> No.
>
> > is this correct? because i feel even if this swap area
> > is not there then also virtual memory concept exists?
>
> Virtual memory is the reason why applications can think they have 4GB
> of memory while your physical machine might actually have only 32MB.
> You don't need to have swap in order to have virtual memory, although
> its very advantageous to have swap with VM.
>
> Virtual memory maps the viurtual pages (from 0 to 4GB) to actually
> physical memory pages (from 0 to however much RAM you have). Swapping
> is the process of using the disk to store physical memory pages when
> they are not in use, and then restoring them when an application
> accesses them.
>
> Pratik.
>
>
> -
> To unsubscribe from this list: send the line "unsubscribe linux-newbie" in
> the body of a message to majordomo@vger.kernel.org
> More majordomo info at http://vger.kernel.org/majordomo-info.html
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>
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^ permalink raw reply [flat|nested] 17+ messages in thread
* Re: VM Vs Swap space
2004-10-07 22:13 ` chuck gelm
2004-10-08 2:49 ` Jim Nelson
@ 2004-10-08 15:25 ` Pratik Solanki
1 sibling, 0 replies; 17+ messages in thread
From: Pratik Solanki @ 2004-10-08 15:25 UTC (permalink / raw)
To: chuck; +Cc: Ankit Jain, linux-newbie
On Thu, 07 Oct 2004 18:13:52 -0400, chuck gelm <chuck@gelm.net> wrote:
> Pratik Solanki wrote:
>
> >[CCing linux-newbie]
> >
> >On Thu, 7 Oct 2004 18:21:57 +0100 (BST), Ankit Jain
> ><ankitjain1580@yahoo.com> wrote:
> >
> >
> >>well i dont know exactly but somewhat i feel that
> >>there must be some way to disable the virtual memory.
> >>yaa of course there should be some way. it is not that
> >>sys cant work without it
> >>
> >>
> >
> >Yes, you can have a system without virtual memory. Search for MMUless
> >linux kernel and you'll see patches/websites.
> >
> >My point was that disabling VM after its been enabled would tough (if
> >not impossible). Someone correct me if I am wrong here.
> >
> >Pratik.
> >
> I was thinking that an active swap partition was 'virtual memory'.
> Why are many folks using capital letters 'VM'. Am I missing
> something? Is 'VM' == virtual memory or is there a application
> or service called 'VM' ?
Yes, VM is virtual memory.
> Anywho, the only 'virtual memory' I know of is an active
> swap file or swap partition and either can be started
> or stopped in a running kernel.
> (I think.)
Swap can be started or stopped. Virtual memory cannot be started or
stopped. Just because you stopped swap does not mean the kernel is not
using virtual memory. The kernel always uses virtual memory (except if
its MMUless) . Swap is used only when the kernel needs more memory
than what's physically available.
Pratik.
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^ permalink raw reply [flat|nested] 17+ messages in thread
end of thread, other threads:[~2004-10-08 15:25 UTC | newest]
Thread overview: 17+ messages (download: mbox.gz follow: Atom feed
-- links below jump to the message on this page --
2004-10-06 8:52 VM Vs Swap space Ankit Jain
2004-10-07 1:57 ` chuck gelm
2004-10-07 6:01 ` kernel kernel
2004-10-07 9:15 ` Ankit Jain
2004-10-07 9:25 ` kernel kernel
2004-10-07 9:37 ` Ankit Jain
2004-10-07 10:31 ` chuck gelm
2004-10-07 16:05 ` Pratik Solanki
2004-10-07 16:07 ` Pratik Solanki
2004-10-08 3:29 ` kernel kernel
2004-10-07 10:41 ` chuck gelm
2004-10-07 16:09 ` Pratik Solanki
[not found] ` <20041007172157.63553.qmail@web52908.mail.yahoo.com>
2004-10-07 18:49 ` Pratik Solanki
2004-10-07 22:13 ` chuck gelm
2004-10-08 2:49 ` Jim Nelson
2004-10-08 15:25 ` Pratik Solanki
[not found] <9cb08bfa04100708182c097689@mail.gmail.com>
[not found] ` <20041007160656.32450.qmail@web52904.mail.yahoo.com>
2004-10-07 16:13 ` Pratik Solanki
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