xref: /openbmc/linux/Documentation/mm/damon/faq.rst (revision 2612e3bbc0386368a850140a6c9b990cd496a5ec)
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3*ee65728eSMike Rapoport==========================
4*ee65728eSMike RapoportFrequently Asked Questions
5*ee65728eSMike Rapoport==========================
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7*ee65728eSMike RapoportDoes DAMON support virtual memory only?
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10*ee65728eSMike RapoportNo.  The core of the DAMON is address space independent.  The address space
11*ee65728eSMike Rapoportspecific monitoring operations including monitoring target regions
12*ee65728eSMike Rapoportconstructions and actual access checks can be implemented and configured on the
13*ee65728eSMike RapoportDAMON core by the users.  In this way, DAMON users can monitor any address
14*ee65728eSMike Rapoportspace with any access check technique.
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16*ee65728eSMike RapoportNonetheless, DAMON provides vma/rmap tracking and PTE Accessed bit check based
17*ee65728eSMike Rapoportimplementations of the address space dependent functions for the virtual memory
18*ee65728eSMike Rapoportand the physical memory by default, for a reference and convenient use.
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21*ee65728eSMike RapoportCan I simply monitor page granularity?
22*ee65728eSMike Rapoport======================================
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24*ee65728eSMike RapoportYes.  You can do so by setting the ``min_nr_regions`` attribute higher than the
25*ee65728eSMike Rapoportworking set size divided by the page size.  Because the monitoring target
26*ee65728eSMike Rapoportregions size is forced to be ``>=page size``, the region split will make no
27*ee65728eSMike Rapoporteffect.
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