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Diffstat (limited to 'qpid/doc/book/src/java-broker/Java-Broker-Runtime-Flow-To-Disk.xml')
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diff --git a/qpid/doc/book/src/java-broker/Java-Broker-Runtime-Flow-To-Disk.xml b/qpid/doc/book/src/java-broker/Java-Broker-Runtime-Flow-To-Disk.xml deleted file mode 100644 index 4ffde911bf..0000000000 --- a/qpid/doc/book/src/java-broker/Java-Broker-Runtime-Flow-To-Disk.xml +++ /dev/null @@ -1,46 +0,0 @@ -<?xml version="1.0" encoding="utf-8"?> -<!-- - - 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. - ---> - -<section id="Java-Broker-Runtime-Flow-To-Disk"> - <title>Flow to Disk</title> - <para>Flow to disk limits the amount of heap memory that can be occupied by messages. Once this - limit is reached any new transient messages and all existing transient messages will be - transferred to disk. Newly arriving transient messages will continue to go to the disk until the - cumulative size of all messages falls below the limit once again.</para> - <para>By default the Broker makes 40% of the max available memory for messages. This memory is - divided between all the queues across all virtual hosts defined on the Broker with a percentage - calculated according to their current queue size. These calculations are refreshed periodically - by the housekeeping cycle.</para> - <para>For example if there are two queues, one containing 75MB and the second 100MB messages - respectively and the Broker has 1GB heap memory with the default of 40% available for messages. - The first queue will have a target size of 170MB and the second 230MB. Once 400MB is taken by - messages, messages will begin to flow to disk. New messages will cease to flow to disk when - their cumulative size falls beneath 400MB.</para> - <para>Flow to disk is configured by Broker context variable - <literal>broker.flowToDiskThreshold</literal>. It is expressed as a size in bytes and defaults - to 40% of the JVM maximum heap size.</para> - <para>Log message <link linkend="Java-Broker-Appendix-Operation-Logging-Message-BRK-1014" - >BRK-1014</link> is written when the feature activates. Once the total space of all messages - decreases below the threshold, the message <link - linkend="Java-Broker-Appendix-Operation-Logging-Message-BRK-1015">BRK-1015</link> is written - to show that the feature is no longer active.</para> -</section> |