Return-Path: X-Original-To: apmail-cassandra-user-archive@www.apache.org Delivered-To: apmail-cassandra-user-archive@www.apache.org Received: from mail.apache.org (hermes.apache.org [140.211.11.3]) by minotaur.apache.org (Postfix) with SMTP id 992A818488 for ; Thu, 24 Sep 2015 19:59:04 +0000 (UTC) Received: (qmail 72875 invoked by uid 500); 24 Sep 2015 19:59:00 -0000 Delivered-To: apmail-cassandra-user-archive@cassandra.apache.org Received: (qmail 72831 invoked by uid 500); 24 Sep 2015 19:59:00 -0000 Mailing-List: contact user-help@cassandra.apache.org; run by ezmlm Precedence: bulk List-Help: List-Unsubscribe: List-Post: List-Id: Reply-To: user@cassandra.apache.org Delivered-To: mailing list user@cassandra.apache.org Received: (qmail 72819 invoked by uid 99); 24 Sep 2015 19:59:00 -0000 Received: from Unknown (HELO spamd1-us-west.apache.org) (209.188.14.142) by apache.org (qpsmtpd/0.29) with ESMTP; Thu, 24 Sep 2015 19:59:00 +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 C63CDC12D9 for ; Thu, 24 Sep 2015 19:58:59 +0000 (UTC) X-Virus-Scanned: Debian amavisd-new at spamd1-us-west.apache.org X-Spam-Flag: NO X-Spam-Score: 2.898 X-Spam-Level: ** X-Spam-Status: No, score=2.898 tagged_above=-999 required=6.31 tests=[DKIM_SIGNED=0.1, DKIM_VALID=-0.1, DKIM_VALID_AU=-0.1, HTML_MESSAGE=3, RCVD_IN_MSPIKE_H2=-0.001, SPF_PASS=-0.001] autolearn=disabled Authentication-Results: spamd1-us-west.apache.org (amavisd-new); dkim=pass (2048-bit key) header.d=gmail.com Received: from mx1-us-east.apache.org ([10.40.0.8]) by localhost (spamd1-us-west.apache.org [10.40.0.7]) (amavisd-new, port 10024) with ESMTP id 0XvbjO8H08Cm for ; Thu, 24 Sep 2015 19:58:59 +0000 (UTC) Received: from mail-oi0-f43.google.com (mail-oi0-f43.google.com [209.85.218.43]) by mx1-us-east.apache.org (ASF Mail Server at mx1-us-east.apache.org) with ESMTPS id E071A439B6 for ; Thu, 24 Sep 2015 19:58:58 +0000 (UTC) Received: by oibi136 with SMTP id i136so47726847oib.3 for ; Thu, 24 Sep 2015 12:58:52 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20120113; h=mime-version:date:message-id:subject:from:to:content-type; bh=a95t2pMbjcdYmp8TNn3vKC382jSMgeyKeIgc2DjihY0=; b=CsV5P4xXZL7xy76u403o7X7AjT2+RWstow5l34LDIfoufLkifiaK0E3CYipm2wrHPU NYAOKOLDiK1jjAV2OZqv+jhPlqPCsAH+sKPT2Xq9vAZizucwYbaiVG6CYkQ6H6n7KPrv Qo+WTbBgOty+WvGX2/uOVHJe7HT7DvS7zCMFWphHt3TTPERtWBOppkORFcdrBVZE40ad x90TsSJ0XFR0NsxTRAJWfyTlJ//RAzctkIub8AIFLvUxQgA1hb6oeyltgt6JYOSg89Bd NeHOhfrek+sgxENTBBSOO+NnFmjw4uAoY8Vb00+ddiWzxV8CcwIQ05lpxV31+71SP9x0 12DQ== MIME-Version: 1.0 X-Received: by 10.202.77.207 with SMTP id a198mr855806oib.131.1443124732006; Thu, 24 Sep 2015 12:58:52 -0700 (PDT) Received: by 10.202.195.195 with HTTP; Thu, 24 Sep 2015 12:58:51 -0700 (PDT) Date: Thu, 24 Sep 2015 12:58:51 -0700 Message-ID: Subject: How to tune Cassandra or Java Driver to get lower latency when there are a lot of writes? From: Benyi Wang To: user Content-Type: multipart/alternative; boundary=001a11352c9604980e052083a98c --001a11352c9604980e052083a98c Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: quoted-printable I have a cassandra cluster provides data to a web service. And there is a daily batch load writing data into the cluster. - Without the batch loading, the service=E2=80=99s Latency 99thPercentil= e is 3ms. But during the load, it jumps to 90ms. - I checked cassandra keyspace=E2=80=99s ReadLatency.99thPercentile, whi= ch jumps to 1ms from 600 microsec. - The service=E2=80=99s cassandra java driver request 99thPercentile was= 90ms during the load The java driver took the most time. I knew the Cassandra servers are busy in writing, but I want to know what kinds of metrics can identify where is the bottleneck so that I can tune it. I=E2=80=99m using Cassandra 2.1.8 and Cassandra Java Driver 2.1.5. =E2=80=8B --001a11352c9604980e052083a98c Content-Type: text/html; charset=UTF-8 Content-Transfer-Encoding: quoted-printable

I have a cassandra cluster provides data to a web service. And= there is a daily batch load writing data into the cluster.

  • Without the batch loading, the service=E2=80= =99s=C2=A0Latency=C2=A099thPercentile is 3ms. But during the load, it jumps= to=C2=A090ms.
  • I checked cassandra keyspace=E2=80=99s ReadL= atency.99thPercentile, which jumps to 1ms from 600 microsec.
  • The service=E2=80=99s cassandra java driver = request 99thPercentile was 90ms during the load

The java driver took the most t= ime. I knew the Cassandra servers are busy in writing, but I want to know w= hat kinds of metrics can identify where is the bottleneck so that I can tun= e it.

I=E2=80=99m using Cassandra 2.1= .8 and Cassandra Java Driver 2.1.5.

=E2=80=8B
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