Return-Path: X-Original-To: archive-asf-public-internal@cust-asf2.ponee.io Delivered-To: archive-asf-public-internal@cust-asf2.ponee.io Received: from cust-asf.ponee.io (cust-asf.ponee.io [163.172.22.183]) by cust-asf2.ponee.io (Postfix) with ESMTP id 30576200BB6 for ; Fri, 4 Nov 2016 22:33:00 +0100 (CET) Received: by cust-asf.ponee.io (Postfix) id 2E622160AEA; Fri, 4 Nov 2016 21:33:00 +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 68CFC160B04 for ; Fri, 4 Nov 2016 22:32:59 +0100 (CET) Received: (qmail 7890 invoked by uid 500); 4 Nov 2016 21:32:58 -0000 Mailing-List: contact notifications-help@accumulo.apache.org; run by ezmlm Precedence: bulk List-Help: List-Unsubscribe: List-Post: List-Id: Reply-To: jira@apache.org Delivered-To: mailing list notifications@accumulo.apache.org Received: (qmail 7780 invoked by uid 99); 4 Nov 2016 21:32:58 -0000 Received: from arcas.apache.org (HELO arcas) (140.211.11.28) by apache.org (qpsmtpd/0.29) with ESMTP; Fri, 04 Nov 2016 21:32:58 +0000 Received: from arcas.apache.org (localhost [127.0.0.1]) by arcas (Postfix) with ESMTP id 6782E2C1F56 for ; Fri, 4 Nov 2016 21:32:58 +0000 (UTC) Date: Fri, 4 Nov 2016 21:32:58 +0000 (UTC) From: "Josh Elser (JIRA)" To: notifications@accumulo.apache.org Message-ID: In-Reply-To: References: Subject: [jira] [Commented] (ACCUMULO-4502) Called next when there is no top MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: 7bit X-JIRA-FingerPrint: 30527f35849b9dde25b450d4833f0394 archived-at: Fri, 04 Nov 2016 21:33:00 -0000 [ https://issues.apache.org/jira/browse/ACCUMULO-4502?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=15637754#comment-15637754 ] Josh Elser commented on ACCUMULO-4502: -------------------------------------- re impact -- http://brooker.co.za/blog/2012/09/10/volatile.html tl;dr for a volatile variable under contention, read performance, with a high variance, can be impacted by 25x and write perf by 100x. Heavily variant due to multi-core and cache lines. I'll see if I can find some time tonight or this weekend to dig into this code myself since you made time to do the same, Ivan. > Called next when there is no top > -------------------------------- > > Key: ACCUMULO-4502 > URL: https://issues.apache.org/jira/browse/ACCUMULO-4502 > Project: Accumulo > Issue Type: Bug > Components: core, tserver > Affects Versions: 1.6.6 > Reporter: Ivan Bella > Assignee: Ivan Bella > Fix For: 1.7.3, 1.8.1, 2.0.0 > > Time Spent: 20m > Remaining Estimate: 0h > > This happens very rarely but we have seen the following exception (pulled from a server running 1.6.4). Looking at the code I believe this condition can still happen in 1.8.0: > java.util.concurrent.ExecutionException: java.lang.IllegalStateException: Called next() when there is no top > ... > Caused by: java.lang.IllegalStateException: Called next() when there is no top > HeapIterator.next(HeapIterator.java: 77) > WrappingIterator.next(WrappingIterator.java: 96) > MemKeyConversionIterator.next(InMemoryMap.java:162) > SourceSwitchingIterator.readNext(SourceSwitchingIterator.java: 139) > SourceSwitchingIterator.next(SourceSwitchingIterator.java: 123) > PartialMutationSkippingIterator.consume(InMemoryMap.java:108) > SkippingIterator.seek(SkippingIterator.java:43) -- This message was sent by Atlassian JIRA (v6.3.4#6332)