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diff --git a/Documentation/vm/damon/faq.rst b/Documentation/vm/damon/faq.rst deleted file mode 100644 index dde7e2414ee6..000000000000 --- a/Documentation/vm/damon/faq.rst +++ /dev/null @@ -1,50 +0,0 @@ -.. SPDX-License-Identifier: GPL-2.0 - -========================== -Frequently Asked Questions -========================== - -Why a new subsystem, instead of extending perf or other user space tools? -========================================================================= - -First, because it needs to be lightweight as much as possible so that it can be -used online, any unnecessary overhead such as kernel - user space context -switching cost should be avoided. Second, DAMON aims to be used by other -programs including the kernel. Therefore, having a dependency on specific -tools like perf is not desirable. These are the two biggest reasons why DAMON -is implemented in the kernel space. - - -Can 'idle pages tracking' or 'perf mem' substitute DAMON? -========================================================= - -Idle page tracking is a low level primitive for access check of the physical -address space. 'perf mem' is similar, though it can use sampling to minimize -the overhead. On the other hand, DAMON is a higher-level framework for the -monitoring of various address spaces. It is focused on memory management -optimization and provides sophisticated accuracy/overhead handling mechanisms. -Therefore, 'idle pages tracking' and 'perf mem' could provide a subset of -DAMON's output, but cannot substitute DAMON. - - -Does DAMON support virtual memory only? -======================================= - -No. The core of the DAMON is address space independent. The address space -specific monitoring operations including monitoring target regions -constructions and actual access checks can be implemented and configured on the -DAMON core by the users. In this way, DAMON users can monitor any address -space with any access check technique. - -Nonetheless, DAMON provides vma/rmap tracking and PTE Accessed bit check based -implementations of the address space dependent functions for the virtual memory -and the physical memory by default, for a reference and convenient use. - - -Can I simply monitor page granularity? -====================================== - -Yes. You can do so by setting the ``min_nr_regions`` attribute higher than the -working set size divided by the page size. Because the monitoring target -regions size is forced to be ``>=page size``, the region split will make no -effect. |