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https://issues.apache.org/jira/browse/ACCUMULO-4187?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=15238562#comment-15238562
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ASF GitHub Bot commented on ACCUMULO-4187:
------------------------------------------

Github user joshelser commented on a diff in the pull request:

    https://github.com/apache/accumulo/pull/90#discussion_r59489957
  
    --- Diff: 
core/src/main/java/org/apache/accumulo/core/file/streams/RateLimitedOutputStream.java
 ---
    @@ -0,0 +1,55 @@
    +/*
    + * Licensed to the Apache Software Foundation (ASF) under one or more
    + * contributor license agreements. See the NOTICE file distributed with 
this
    + * work for additional information regarding copyright ownership. The ASF
    + * licenses this file to you under the Apache License, Version 2.0 (the
    + * "License"); you may not use this file except in compliance with the 
License.
    + * You may obtain a copy of the License at
    + *
    + * http://www.apache.org/licenses/LICENSE-2.0
    + *
    + * Unless required by applicable law or agreed to in writing, software
    + * distributed under the License is distributed on an "AS IS" BASIS, 
WITHOUT
    + * WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
    + * License for the specific language governing permissions and limitations 
under
    + * the License.
    + */
    +package org.apache.accumulo.core.file.streams;
    +
    +import java.io.FilterOutputStream;
    +import java.io.IOException;
    +import java.io.OutputStream;
    +import org.apache.accumulo.core.util.ratelimit.NullRateLimiter;
    +import org.apache.accumulo.core.util.ratelimit.RateLimiter;
    +
    +/** A decorator for {@code OutputStream} which limits the rate at which 
data may be written. */
    --- End diff --
    
    Expand the comment (style-nit)


> Rate limiting of major compactions
> ----------------------------------
>
>                 Key: ACCUMULO-4187
>                 URL: https://issues.apache.org/jira/browse/ACCUMULO-4187
>             Project: Accumulo
>          Issue Type: Improvement
>          Components: core, tserver
>    Affects Versions: 1.8.0
>            Reporter: Shawn Walker
>            Assignee: Shawn Walker
>            Priority: Minor
>             Fix For: 1.8.0
>
>
> In discussing [ACCUMULO-4166] with Keith Turner, we decided that the 
> underlying issue is that major compactions can overwhelm a tablet server, 
> rendering it nearly unresponsive.
> To address this, we should take a cue from Apache Cassandra and restrict how 
> quickly we perform major compactions.  Rate limiting reads and writes 
> involved in major compactions will directly affect the IO load caused by 
> major compactions, and should also indirectly affect the CPU load.



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