Received: by 2002:a05:6358:9144:b0:117:f937:c515 with SMTP id r4csp8450614rwr; Thu, 11 May 2023 01:08:58 -0700 (PDT) X-Google-Smtp-Source: ACHHUZ6+rr5UwFe12y3qmt7etImizB6U4hHdW1lCG3mVDJR1Y5h1zddMs+mlTJy8aBS+q9n5ym+R X-Received: by 2002:a05:6a20:54a4:b0:101:1951:d491 with SMTP id i36-20020a056a2054a400b001011951d491mr13202406pzk.6.1683792538677; Thu, 11 May 2023 01:08:58 -0700 (PDT) ARC-Seal: i=1; a=rsa-sha256; t=1683792538; cv=none; d=google.com; s=arc-20160816; b=VqvE0o3Rt1qIMcEB8bTnhI89M7jSV+zoMs4Vd9u6V+7fhRa0oLAn7FJnipBsmYMCXJ m44j3A6Ua5DGONnHQyf4ViCkKTCgwnA3NNWv+d8kyzH1Ao+/+FZsPVSICJ9wn56UP97i LfVIJdTMhVdaUURGJ0mxoxnFD6puNMuYJqMs2fA6aw3lWyKMm/3t9UgF5NoJopqduyps 47/fhKWX3pbRWgQtDmzPVaxAVLCiS0D9HsDhnqfPa59DDIK/B5aN1l6K5v7IJdpYg22b MczDU3s9jde3LB0OX/etM9fKDMOTIDKplRcKQ3/iuINHuMEFvDi7OT52ULmGaTlxfMLt KLng== ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=arc-20160816; h=list-id:precedence:in-reply-to:content-disposition:mime-version :references:message-id:subject:cc:to:from:date:dkim-signature; bh=+CGH7YHU79D1x2zo+JX/L+1Yeo4Kpnw8RAg9mt4T5fI=; b=pwQx+QR7ARx+kSM41twg9b51BYC6hVLG229l/GVCHA3u6UPubaG6RocnZgPPR+spGp F0I2B7MEboN4LQYvZyxF1TXfEfVR+E/XYFURxvKH2vh03YisWq/FT74U6xhjxCauZWTG JJUIX9K3XebsSZybOKNFV4BoKbMxkt00WWhsr1Eju/lUhssKNBtaaGucJZ5xl0hWOnNd cD7hE5MR9IaKK2fS7QFUiP259XYUmXhZZgxVRPJDSTlbJwQYzwoCiofV759My8zZdLD9 iLP01GJVXLlA80yIxB489XcPCRAe4sl6nq9WEB9sX/wHFp3O9KWBxAF0c6+XSDo5VEAZ KbkQ== ARC-Authentication-Results: i=1; mx.google.com; dkim=pass header.i=@infradead.org header.s=desiato.20200630 header.b=JaYNfxN6; spf=pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 2620:137:e000::1:20 as permitted sender) smtp.mailfrom=linux-kernel-owner@vger.kernel.org Return-Path: Received: from out1.vger.email (out1.vger.email. [2620:137:e000::1:20]) by mx.google.com with ESMTP id y8-20020aa793c8000000b0063732344e2fsi6915486pff.190.2023.05.11.01.08.46; Thu, 11 May 2023 01:08:58 -0700 (PDT) Received-SPF: pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 2620:137:e000::1:20 as permitted sender) client-ip=2620:137:e000::1:20; Authentication-Results: mx.google.com; dkim=pass header.i=@infradead.org header.s=desiato.20200630 header.b=JaYNfxN6; spf=pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 2620:137:e000::1:20 as permitted sender) smtp.mailfrom=linux-kernel-owner@vger.kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S237502AbjEKH5A (ORCPT + 99 others); Thu, 11 May 2023 03:57:00 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:57036 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231625AbjEKH46 (ORCPT ); Thu, 11 May 2023 03:56:58 -0400 Received: from desiato.infradead.org (desiato.infradead.org [IPv6:2001:8b0:10b:1:d65d:64ff:fe57:4e05]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id E1BB6269E for ; Thu, 11 May 2023 00:56:56 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=infradead.org; s=desiato.20200630; h=In-Reply-To:Content-Type:MIME-Version: References:Message-ID:Subject:Cc:To:From:Date:Sender:Reply-To: Content-Transfer-Encoding:Content-ID:Content-Description; bh=+CGH7YHU79D1x2zo+JX/L+1Yeo4Kpnw8RAg9mt4T5fI=; b=JaYNfxN6UpDjkg5TCFsg9BwlN+ c3txs50rIc3hX+JmCPER1Hf2OJ0PvJ42OxnSzvJ0Vbi2Mta7+67wKYBtcaDiQmphbwPBIJ3GZEr5m zZlA0Sy/tUFu4dFj327ul1jgXZhqfOJ2HcaSXe2NzKlloGT5etzz4BaWeV4u7zZHeFe+BOhyCIZZV DBHeUz2iirtSu7ToxV5lgyWz+5QtGJJ7fd7I9qmEtdvZWpKosNwMZQ/VuhYRBPBfji7KY+5vSBLs3 TpPTaXhpTweZBq8I+hJKrv3Yh/wC7S5t59n+xdZScabJ9jlSJ0DBAjL0YpZJp9FuQKLJswTHJ+uzG AXpqQ42A==; Received: from j130084.upc-j.chello.nl ([24.132.130.84] helo=noisy.programming.kicks-ass.net) by desiato.infradead.org with esmtpsa (Exim 4.96 #2 (Red Hat Linux)) id 1px1AA-008AyE-2u; Thu, 11 May 2023 07:56:35 +0000 Received: from hirez.programming.kicks-ass.net (hirez.programming.kicks-ass.net [192.168.1.225]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (4096 bits)) (Client did not present a certificate) by noisy.programming.kicks-ass.net (Postfix) with ESMTPS id B7948300023; Thu, 11 May 2023 09:56:32 +0200 (CEST) Received: by hirez.programming.kicks-ass.net (Postfix, from userid 1000) id 5D70C235CC442; Thu, 11 May 2023 09:56:32 +0200 (CEST) Date: Thu, 11 May 2023 09:56:32 +0200 From: Peter Zijlstra To: Pavel Tikhomirov Cc: Thomas Gleixner , Frederic Weisbecker , LKML , Anna-Maria Behnsen , syzbot+5c54bd3eb218bb595aa9@syzkaller.appspotmail.com, Dmitry Vyukov , Sebastian Siewior , Michael Kerrisk , Andrei Vagin , Christian Brauner , Alexander Mikhalitsyn , Pavel Emelyanov Subject: Re: [RFD] posix-timers: CRIU woes Message-ID: <20230511075632.GR4253@hirez.programming.kicks-ass.net> References: <87zg6i2xn3.ffs@tglx> <87v8h62vwp.ffs@tglx> <878rdy32ri.ffs@tglx> <87v8h126p2.ffs@tglx> <875y911xeg.ffs@tglx> <87ednpyyeo.ffs@tglx> <009e7658-1377-cc79-7a42-4dda8fec5af0@virtuozzo.com> <87wn1gy4e6.ffs@tglx> <005a944c-ed2e-6010-a534-26d5947402da@virtuozzo.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <005a944c-ed2e-6010-a534-26d5947402da@virtuozzo.com> X-Spam-Status: No, score=-4.4 required=5.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,DKIM_VALID_EF,RCVD_IN_DNSWL_MED,SPF_HELO_NONE, SPF_NONE,T_SCC_BODY_TEXT_LINE autolearn=ham autolearn_force=no version=3.4.6 X-Spam-Checker-Version: SpamAssassin 3.4.6 (2021-04-09) on lindbergh.monkeyblade.net Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Thu, May 11, 2023 at 12:12:32PM +0800, Pavel Tikhomirov wrote: > Not sure how kernel memory consumption increases with sparse timer IDs, > global hashtable (posix_timers_hashtable) is the same size anyway, entries > in hlists can be distributed differently as hash depends on id directly but > we have same number of entries. Probably I miss something, why do we need > dense IDs? The proposal was to remove the global hash and use a signal_struct based xarray instead.