From issues-return-54880-archive-asf-public=cust-asf.ponee.io@ignite.apache.org Fri Jan 12 12:52:11 2018 Return-Path: X-Original-To: archive-asf-public@eu.ponee.io Delivered-To: archive-asf-public@eu.ponee.io Received: from cust-asf.ponee.io (cust-asf.ponee.io [163.172.22.183]) by mx-eu-01.ponee.io (Postfix) with ESMTP id DD82F180621 for ; Fri, 12 Jan 2018 12:52:11 +0100 (CET) Received: by cust-asf.ponee.io (Postfix) id C6DB0160C33; Fri, 12 Jan 2018 11:52:11 +0000 (UTC) Delivered-To: archive-asf-public@cust-asf.ponee.io Received: from mail.apache.org (hermes.apache.org [140.211.11.3]) by cust-asf.ponee.io (Postfix) with SMTP id 163C5160C30 for ; Fri, 12 Jan 2018 12:52:10 +0100 (CET) Received: (qmail 86798 invoked by uid 500); 12 Jan 2018 11:52:10 -0000 Mailing-List: contact issues-help@ignite.apache.org; run by ezmlm Precedence: bulk List-Help: List-Unsubscribe: List-Post: List-Id: Reply-To: dev@ignite.apache.org Delivered-To: mailing list issues@ignite.apache.org Received: (qmail 86789 invoked by uid 99); 12 Jan 2018 11:52:10 -0000 Received: from pnap-us-west-generic-nat.apache.org (HELO spamd3-us-west.apache.org) (209.188.14.142) by apache.org (qpsmtpd/0.29) with ESMTP; Fri, 12 Jan 2018 11:52:10 +0000 Received: from localhost (localhost [127.0.0.1]) by spamd3-us-west.apache.org (ASF Mail Server at spamd3-us-west.apache.org) with ESMTP id DE8E8180624 for ; Fri, 12 Jan 2018 11:52:09 +0000 (UTC) X-Virus-Scanned: Debian amavisd-new at spamd3-us-west.apache.org X-Spam-Flag: NO X-Spam-Score: -107.911 X-Spam-Level: X-Spam-Status: No, score=-107.911 tagged_above=-999 required=6.31 tests=[ENV_AND_HDR_SPF_MATCH=-0.5, KAM_ASCII_DIVIDERS=0.8, RCVD_IN_DNSWL_LOW=-0.7, SPF_PASS=-0.001, T_RP_MATCHES_RCVD=-0.01, USER_IN_DEF_SPF_WL=-7.5, USER_IN_WHITELIST=-100] autolearn=disabled Received: from mx1-lw-eu.apache.org ([10.40.0.8]) by localhost (spamd3-us-west.apache.org [10.40.0.10]) (amavisd-new, port 10024) with ESMTP id MQ-iktBDA2id for ; Fri, 12 Jan 2018 11:52:09 +0000 (UTC) Received: from mailrelay1-us-west.apache.org (mailrelay1-us-west.apache.org [209.188.14.139]) by mx1-lw-eu.apache.org (ASF Mail Server at mx1-lw-eu.apache.org) with ESMTP id B9EDA5F36A for ; Fri, 12 Jan 2018 11:52:08 +0000 (UTC) Received: from jira-lw-us.apache.org (unknown [207.244.88.139]) by mailrelay1-us-west.apache.org (ASF Mail Server at mailrelay1-us-west.apache.org) with ESMTP id 4B57DE0ECF for ; Fri, 12 Jan 2018 11:52:06 +0000 (UTC) Received: from jira-lw-us.apache.org (localhost [127.0.0.1]) by jira-lw-us.apache.org (ASF Mail Server at jira-lw-us.apache.org) with ESMTP id DCDC425BD5 for ; Fri, 12 Jan 2018 11:52:02 +0000 (UTC) Date: Fri, 12 Jan 2018 11:52:02 +0000 (UTC) From: "Andrey Gura (JIRA)" To: issues@ignite.apache.org Message-ID: In-Reply-To: References: Subject: [jira] [Commented] (IGNITE-6736) Java 9: rework GridCacheMapEntry synchronization logic to avoid Unsafe.monitor* methods MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: 7bit X-JIRA-FingerPrint: 30527f35849b9dde25b450d4833f0394 [ https://issues.apache.org/jira/browse/IGNITE-6736?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=16323860#comment-16323860 ] Andrey Gura commented on IGNITE-6736: ------------------------------------- LGTM. Perfromance tests are ok. But now we have additional memory overhead on each entry. Merged to master branch. > Java 9: rework GridCacheMapEntry synchronization logic to avoid Unsafe.monitor* methods > --------------------------------------------------------------------------------------- > > Key: IGNITE-6736 > URL: https://issues.apache.org/jira/browse/IGNITE-6736 > Project: Ignite > Issue Type: Task > Components: cache > Reporter: Vladimir Ozerov > Assignee: Andrey Kuznetsov > Fix For: 2.4 > > > {{GridCacheMapEntry}} class rely on {{synchronized}} on itself heavily. In {{ATOMIC}} caches we lock multiple entries at once using {{Unsafe.monitorEnter/Exit}} methods. Unfortunately these methods were removed in Java 9. Recursion is not an option, as it would cause stack overflow for {{putAll}} operations with multiple entries. > Possible fixes: > 1) Rework {{synchronized}} to {{ReentrantLock}}. Easy, but may cause additional memory pressure. > 2) Have different implementations for Java 8 ({{synchronzied}}) and Java 9 ({{ReentrantLock}}) - much more complex solution, because we will require separate module for Java 8 and Java 9. > 3) Rework {{ATOMIC}} caches, so that {{putAll}} operation updates entries one-by-one. As a side effect it will eliminate deadlocks. -- This message was sent by Atlassian JIRA (v6.4.14#64029)