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Peter Anvin" , Matthew Wilcox , Kent Overstreet , "linux-kernel@vger.kernel.org" , "linux-mm@kvack.org" , "akpm@linux-foundation.org" , "x86@kernel.org" , "bp@alien8.de" , "brauner@kernel.org" , "bristot@redhat.com" , "bsegall@google.com" , "dave.hansen@linux.intel.com" , "dianders@chromium.org" , "dietmar.eggemann@arm.com" , "eric.devolder@oracle.com" , "hca@linux.ibm.com" , "hch@infradead.org" , "jacob.jun.pan@linux.intel.com" , "jgg@ziepe.ca" , "jpoimboe@kernel.org" , "jroedel@suse.de" , "juri.lelli@redhat.com" , "kinseyho@google.com" , "kirill.shutemov@linux.intel.com" , "lstoakes@gmail.com" , "luto@kernel.org" , "mgorman@suse.de" , "mic@digikod.net" , "michael.christie@oracle.com" , "mingo@redhat.com" , "mjguzik@gmail.com" , "mst@redhat.com" , "npiggin@gmail.com" , "peterz@infradead.org" , "pmladek@suse.com" , "rick.p.edgecombe@intel.com" , "rostedt@goodmis.org" , "surenb@google.com" , "tglx@linutronix.de" , "urezki@gmail.com" , "vincent.guittot@linaro.org" , "vschneid@redhat.com" Content-Type: text/plain; charset="UTF-8" X-Rspamd-Queue-Id: B7DD3140017 X-Rspam-User: X-Rspamd-Server: rspam04 X-Stat-Signature: jyjijbyod6moda1yae458pzbp6ke4k5b X-HE-Tag: 1710783488-169796 X-HE-Meta: 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 P/9DV1c6 PY9dDJhPZx00A3m7eWrfYBJ3UxesWNxIBUjxJ3q/NJ9uNq6PmcrFQEBqquofJgoPH7fUWUQdd3I0GfV/UkhWL40wPT82cAiPkZUVmPB1KtJAa24F3/pdVOkwQdLXwatMwogmYQRuGa0ZVQkzP0TTzsSxw1Mg3kdzNYjWZSrOdERyJH0ObIlNOYCdf3o/dfmialO4nbc9f57Gr5CrAG0gEqPQMzCFFQruXk9UoClLw3n6gGYOmf2k4WzzqiXCYtlLpgxLk63VhptnVvjRrBBQ4WsmzwmePshD6zseVUZaC1yOHOt8oYlBmfaHFZMcK+mf2Ijz9jxYfW+U2gqKOQO+w7wX1zvopkRJjiHn5 X-Bogosity: Ham, tests=bogofilter, spamicity=0.000014, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: List-Subscribe: List-Unsubscribe: > > Perhaps a 'garbage collection' activity that reclaims stack > > pages from processes that have been asleep 'for a while' or > > haven't used a lot of stack recently (if hw 'page accessed' > > bit can be used) might make more sense. Interesting approach: if we take the original Andy's suggestion of using an access bit to know which stack pages were never used during context switch and unmap them, and as an extra optimization have a "garbage collector" that unmaps stacks in some long sleeping rarely used threads. I will think about this. Thanks, Pasha