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[79.227.161.199]) by smtp.gmail.com with ESMTPSA id w25-20020a1709064a1900b00a524dda47c0sm9887901eju.143.2024.04.25.11.53.46 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Thu, 25 Apr 2024 11:53:47 -0700 (PDT) In-Reply-To: <87sez9fhzk.fsf@gmail.com> (Helmut Eller's message of "Thu, 25 Apr 2024 19:51:43 +0200") Received-SPF: pass client-ip=2a00:1450:4864:20::62c; envelope-from=gerd.moellmann@gmail.com; helo=mail-ej1-x62c.google.com X-Spam_score_int: -19 X-Spam_score: -2.0 X-Spam_bar: -- X-Spam_report: (-2.0 / 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, URIBL_SBL_A=0.1 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:318095 Archived-At: Helmut Eller writes: > I'd also have some MPS related questions. Just curiosity. > > 1) Does somebody have experience with this MMTK [https://www.mmtk.io/]? > How does it compare to MPS? Can't say much, I'm afraid. ISTR that it is relatively young, and they said somewhere that they are not for production use yet (ca. half a year ago). That's about what I recall. And it's Rust, if that matters. > 2) When I learned that MPS uses hardware based read barriers, I was > surprised. I had somewhere in the back of my mind some vague > memory/opinion that those are too slow to be practical. But I actually > don't know why that should be the case. Can somebody explain what the > problem with hardware based read barriers could be? I pass. > 3) MPS uses a mostly-copying strategy. Copying works well for > short-lived objects. For long-lived objects it's not so great. The big > guys (OpenJDK, V8 etc.) switch to mark-compact or something else for > older generations. Does MPS do something special for long-lived > objects? I haven't seen something mentioned in the docs.