From jira-return-9874-archive-asf-public=cust-asf.ponee.io@kafka.apache.org Mon Feb 12 21:39:05 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 46052180652 for ; Mon, 12 Feb 2018 21:39:05 +0100 (CET) Received: by cust-asf.ponee.io (Postfix) id 35ECB160C3F; Mon, 12 Feb 2018 20:39:05 +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 55EE8160C30 for ; Mon, 12 Feb 2018 21:39:04 +0100 (CET) Received: (qmail 45160 invoked by uid 500); 12 Feb 2018 20:39:03 -0000 Mailing-List: contact jira-help@kafka.apache.org; run by ezmlm Precedence: bulk List-Help: List-Unsubscribe: List-Post: List-Id: Reply-To: jira@kafka.apache.org Delivered-To: mailing list jira@kafka.apache.org Received: (qmail 45149 invoked by uid 99); 12 Feb 2018 20:39:03 -0000 Received: from pnap-us-west-generic-nat.apache.org (HELO spamd1-us-west.apache.org) (209.188.14.142) by apache.org (qpsmtpd/0.29) with ESMTP; Mon, 12 Feb 2018 20:39:03 +0000 Received: from localhost (localhost [127.0.0.1]) by spamd1-us-west.apache.org (ASF Mail Server at spamd1-us-west.apache.org) with ESMTP id 14B60C1897 for ; Mon, 12 Feb 2018 20:39:03 +0000 (UTC) X-Virus-Scanned: Debian amavisd-new at spamd1-us-west.apache.org X-Spam-Flag: NO X-Spam-Score: -110.311 X-Spam-Level: X-Spam-Status: No, score=-110.311 tagged_above=-999 required=6.31 tests=[ENV_AND_HDR_SPF_MATCH=-0.5, RCVD_IN_DNSWL_MED=-2.3, 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 (spamd1-us-west.apache.org [10.40.0.7]) (amavisd-new, port 10024) with ESMTP id s7524AgUCTVq for ; Mon, 12 Feb 2018 20:39:02 +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 42FE25F522 for ; Mon, 12 Feb 2018 20:39:01 +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 4F555E0047 for ; Mon, 12 Feb 2018 20:39:00 +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 093F321E84 for ; Mon, 12 Feb 2018 20:39:00 +0000 (UTC) Date: Mon, 12 Feb 2018 20:39:00 +0000 (UTC) From: "Ashish Surana (JIRA)" To: jira@kafka.apache.org Message-ID: In-Reply-To: References: Subject: [jira] [Updated] (KAFKA-6555) Making state store queryable during restoration MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: quoted-printable X-JIRA-FingerPrint: 30527f35849b9dde25b450d4833f0394 [ https://issues.apache.org/jira/browse/KAFKA-6555?page=3Dcom.atlassia= n.jira.plugin.system.issuetabpanels:all-tabpanel ] Ashish Surana updated KAFKA-6555: --------------------------------- Description:=20 State store in Kafka streams are currently only queryable when StreamTask i= s in RUNNING state. The idea is to make it queryable even in the RESTORATIO= N (PARTITION_ASSIGNED) state as the time spend on restoration can be huge a= nd making the data inaccessible during this time could be downtime not suit= able for many applications. When the=C2=A0active partition goes down then one of the following occurs: # One of the standby replica partition gets promoted to active: Replica ta= sk has to restore the remaining state from the changelog topic before it ca= n become RUNNING. The time taken for this depends on how=C2=A0much=C2=A0the= replica is lagging behind. During this restoration time the state store fo= r that partition is currently not queryable giving making the partition dow= n. We can make the state store partition queryable for the data already pre= sent in the state store. # When there is no replica or standby task, then active task will be start= ed in one of the existing node. That node has to build the entire state fro= m the changelog topic which can take lot of time depending on how big is th= e changelog topic, and keeping state store not queryable during this time i= s the downtime for the parition. It's very important improvement as it could simply improve the availability= of microservices developed using kafka streams. Any feedback or comments a= re welcome. =C2=A0 =C2=A0 was: State store in Kafka streams are currently only queryable when StreamTask i= s in RUNNING state. The idea is to make it queryable even in the RESTORATIO= N (PARTITION_ASSIGNED) state as the time spend on restoration can be huge a= nd making the data inaccessible during this time could be downtime not suit= able for many applications. When the=C2=A0active partition goes down then one of the following occurs: # One of the standby replica partition gets promoted to active: Replica ta= sk has to restore the remaining state from the changelog topic before it ca= n become RUNNING. The time taken for this depends on how=C2=A0much=C2=A0the= replica is lagging behind. During this restoration time the state store fo= r that partition is currently not queryable giving making the partition dow= n. We can make the state store partition queryable for the data already pre= sent in the state store. # When there is no replica or standby task, then active task will be start= ed in one of the existing node. That node has to build the entire state fro= m the changelog topic which can take lot of time depending on how big is th= e changelog topic, and keeping state store not queryable during this time i= s the downtime for the parition. =C2=A0 It's very important improvement as it could simply improve the availability= of microservices developed using kafka streams. Any feedback or comments a= re welcome. =C2=A0 =C2=A0 > Making state store queryable during restoration > ----------------------------------------------- > > Key: KAFKA-6555 > URL: https://issues.apache.org/jira/browse/KAFKA-6555 > Project: Kafka > Issue Type: Improvement > Components: streams > Reporter: Ashish Surana > Priority: Major > > State store in Kafka streams are currently only queryable when StreamTask= is in RUNNING state. The idea is to make it queryable even in the RESTORAT= ION (PARTITION_ASSIGNED) state as the time spend on restoration can be huge= and making the data inaccessible during this time could be downtime not su= itable for many applications. > When the=C2=A0active partition goes down then one of the following occurs= : > # One of the standby replica partition gets promoted to active: Replica = task has to restore the remaining state from the changelog topic before it = can become RUNNING. The time taken for this depends on how=C2=A0much=C2=A0t= he replica is lagging behind. During this restoration time the state store = for that partition is currently not queryable giving making the partition d= own. We can make the state store partition queryable for the data already p= resent in the state store. > # When there is no replica or standby task, then active task will be sta= rted in one of the existing node. That node has to build the entire state f= rom the changelog topic which can take lot of time depending on how big is = the changelog topic, and keeping state store not queryable during this time= is the downtime for the parition. > It's very important improvement as it could simply improve the availabili= ty of microservices developed using kafka streams. Any feedback or comments= are welcome. > =C2=A0 > =C2=A0 -- This message was sent by Atlassian JIRA (v7.6.3#76005)