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[79.227.167.252]) by smtp.gmail.com with ESMTPSA id 4fb4d7f45d1cf-58613815dd7sm4686884a12.43.2024.07.01.11.20.38 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Mon, 01 Jul 2024 11:20:39 -0700 (PDT) In-Reply-To: <1osQTI7Swoo72EJbCzzi4zqVXuC5hSlYEXwLtnal8_pyYL7oRCNSJg20XgBRjffZ344Wj7lwFDc9JSMsQ-3su6uXQ8hYSfYleRn-4GRrykI=@protonmail.com> (Pip Cet's message of "Mon, 01 Jul 2024 17:14:11 +0000") 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: -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:321050 Archived-At: Pip Cet writes: >> Could you please send me something from git format-patch? That way I'd >> have commit message and your authorship would also be clear. Or even >> better, if you have the rights could you please commit to the branch? > > I'll do that. Please let me know what I got wrong. Very good =F0=9F=91=8D! >> Yes, it's not eagerly splatting. Don't know. Which reminds me that I >> wanted to look if the AWL pool maybe has some paramter that one could >> set, or something else influences that, like the mortality rate of the >> generation chain. Or something completely different. > > I debugged this a little, and it turns out that when we alternate > between two weak hash tables, splatting works fine. It seems that if > MPS receives a SIGSEGV in a segment belonging to a weak hash table, it > scans it in "exact" mode, not "weak" mode, in order to continue > execution as soon as possible. That's how I read this comment in > mps/trace.c: > > * If the trace band is EXACT then we scan EXACT. This might prevent > * finalisation messages and may preserve objects pointed to only by weak > * references but tough luck -- the mutator wants to look. > > So I don't think this will be a problem in practice... Thanks, that is interesting!