Re: Copy-on-Write memory management



On Apr 25, 9:43 pm, Andrew Tomazos <and...@xxxxxxxxxxx> wrote:
On Apr 26, 1:04 am, Michael  Mol <mike...@xxxxxxxxx> wrote:



On Apr 25, 6:48 pm, Andrew Tomazos <and...@xxxxxxxxxxx> wrote:

On Apr 26, 12:26 am, Michael  Mol <mike...@xxxxxxxxx> wrote:

Let's say I wanted to implement a memory management system where I can
allocate a block of memory, write some data to it, and then clone it
in such a way that two separate pieces of code could own a copy of the
data, write to their copy, and when they read from their copy, they
saw their own written data there.

Now let's say that I want the clone operation to not result in an
increase in my footprint in the system memory until it was necessary
to write to the copy of the data.

Which operating systems, runtimes, libraries, architectures or
patterns have facilities which make this less difficult than it would
be without the facilities they provide?

(It's related to a performance-robustness balance problem I
occasionally encounter at work, but I'm mostly interested out of
personal curiosity; If my question seems ambiguous, it's because I'm
not looking for knowledge, not an exact solution.)

http://en.wikipedia.org/wiki/Copy_on_write

Because Wikipedia takes pains to avoid being too technical, its
notability policies and its tendency to flag non-statistically-
aggregated experience as "original research", it doesn't and won't
have much information on the subject (I checked), and certainly isn't
the place for active discussion. (And this isn't the place to debate
Wikipedia's policies, either; I'm just explaining why they don't have
the information I'm looking for, at the risk of goig offtopic.)

It wasn't my intention to suggest that your post was in any way
inappropriate.  I was just adding a relevant link to the thread.
   -Andrew.

My apologies. I'm used to getting RTFM responses when I've either
already RTFM'd or when TFM is incomplete. I shouldn't have been so
touchy.

Mike Mol.
.



Relevant Pages

  • Re: Copy-on-Write memory management
    ... allocate a block of memory, write some data to it, and then clone it ... in such a way that two separate pieces of code could own a copy of the ... patterns have facilities which make this less difficult than it would ... notability policies and its tendency to flag non-statistically- ...
    (comp.programming)
  • Re: Copy-on-Write memory management
    ... allocate a block of memory, write some data to it, and then clone it ... in such a way that two separate pieces of code could own a copy of the ... patterns have facilities which make this less difficult than it would ... notability policies and its tendency to flag non-statistically- ...
    (comp.programming)
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