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[217.227.106.148]) by smtp.gmail.com with ESMTPSA id gh13-20020a170906e08d00b00a58bf434876sm1306430ejb.58.2024.05.02.22.42.17 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Thu, 02 May 2024 22:42:17 -0700 (PDT) In-Reply-To: (Andrea Corallo's message of "Thu, 02 May 2024 17:25:27 -0400") Received-SPF: pass client-ip=2a00:1450:4864:20::62a; envelope-from=gerd.moellmann@gmail.com; helo=mail-ej1-x62a.google.com X-Spam_score_int: -20 X-Spam_score: -2.1 X-Spam_bar: -- X-Spam_report: (-2.1 / 5.0 requ) BAYES_00=-1.9, DKIM_SIGNED=0.1, DKIM_VALID=-0.1, DKIM_VALID_AU=-0.1, DKIM_VALID_EF=-0.1, FREEMAIL_FROM=0.001, RCVD_IN_DNSWL_NONE=-0.0001, SPF_HELO_NONE=0.001, SPF_PASS=-0.001 autolearn=ham autolearn_force=no X-Spam_action: no action X-BeenThere: emacs-devel@gnu.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: "Emacs development discussions." List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: emacs-devel-bounces+ged-emacs-devel=m.gmane-mx.org@gnu.org Original-Sender: emacs-devel-bounces+ged-emacs-devel=m.gmane-mx.org@gnu.org Xref: news.gmane.io gmane.emacs.devel:318628 Archived-At: Andrea Corallo writes: >> I think MPS is a concurrent GC, it means it runs "all the time". The >> reason why his works are the memory barriers. But maybe Gerd knows how >> things actually work. > > It is still very unclear how it can move objects "all the time". During > execution traced objects can be loaded on the stack and unloaded all the > time (Eli showed other examples of that) so I don't see ATM how it can > move objects without actually pausing the mutator thread. Ja, all the time is maybe a bit too coarse grained an expression. Maybe one could say it this way: MPS is concurrent and incremental, with the two together meaning that it does its work in chunks in another thread. Insofar it's not all the time but in chunks. Don't know if that helps.