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How does Windows' modified memory work without a pagefile? The physical memory is modified and then...? I'm running Windows 7 with 16GB of RAM and no pagefile. I have about 2.5GB of modified memory, most of it belonging to Firefox and Vmware processes.

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modified means that the memory previously belonged to a working set but was removed. However, the data were modified while it was in use and its current contents haven’t yet been written to disk or remote storage. The PTE still refers to the physical page but is marked invalid and in transition. It must be written to the backing store before the physical page can be reused.

When Firefox or VMware modified data are are in the modified list.

You should read the Windows Internals Book 6 (Chapter 10 - Memory Management) for more details.

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Backing store? You mean pagefile? What if there is no backing store? If the memory was removed from the working set then it's no longer relevant, correct? – test Dec 23 '13 at 3:53
no, the data itself are modified in RAM and now the data on the disk must be replaced with the modified data. This has nothing to to with the pagefile. – magicandre1981 Dec 23 '13 at 6:41
I tried RAMmap to flush the modified memory but it doesn't seem to make a difference. Are you saying these are files that were modified in memory and now those modifications must be written back to disk? – test Dec 24 '13 at 8:02
yes they must be written back to disk. – magicandre1981 Dec 25 '13 at 6:54
Unless they're private pages and the process that modified them exits. Then the private modified pages are just released to the standby list. Modified pages mapped to files still get written back to their respective files (backing stores). – Jamie Hanrahan Jul 18 '15 at 13:32

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