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Re^4: Huge perl binary file

by perl-diddler (Hermit)
on Jul 13, 2012 at 04:55 UTC ( #981557=note: print w/ replies, xml ) Need Help??


in reply to Re^3: Huge perl binary file
in thread Huge perl binary file

No. If you have a process of the static binary already running, it will not be loaded again from disk but the same physical memory will simply be mapped to a new virtual address space for the new process. That's the time to set up a few MMU tables and you're ready.
Um...no...only the R/O sections. Programs have initialized R/W spaces that once written are gone. There'd be no reason to have those sections marked as COW, unless you already had someone sharing the page (like a forked copy). But any unrelated process likely wouldn't use a COW copy, as they'd need the pristine data as it was supposed to be when the program loaded.


Comment on Re^4: Huge perl binary file
Re^5: Huge perl binary file
by mbethke (Hermit) on Jul 13, 2012 at 21:40 UTC
    Um...no...only the R/O sections. Programs have initialized R/W spaces that once written are gone. There'd be no reason to have those sections marked as COW, unless you already had someone sharing the page (like a forked copy). But any unrelated process likely wouldn't use a COW copy, as they'd need the pristine data as it was supposed to be when the program loaded.
    Sure, any overview of virtual memory processes this length is bound to be oversimplified in some place. But we can safely ignore this detail as it doesn't differ between dynamically vs. statically linked programs.

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