突然间，工作一个月后几乎没有使用cpu（1到5％之间）。 neo4j服务器在垃圾收集时卡在100％cpu上。
我在ubuntu 4处理器服务器上运行neo4j-entherprise 2.0.3（非嵌入式）。
这是我的neo4j配置： 包装器：
wrapper.java.additional=-Dorg.neo4j.server.properties=conf/neo4j-server.properties
wrapper.java.additional=-Djava.util.logging.config.file=conf/logging.properties
wrapper.java.additional=-Dlog4j.configuration=file:conf/log4j.properties
#********************************************************************
# JVM Parameters
#********************************************************************
wrapper.java.additional=-XX:+UseConcMarkSweepGC
wrapper.java.additional=-XX:+CMSClassUnloadingEnabled
# Remote JMX monitoring, uncomment and adjust the following lines as needed.
# Also make sure to update the jmx.access and jmx.password files with appropriate permission roles and passwords,
# the shipped configuration contains only a read only role called 'monitor' with password 'Neo4j'.
# For more details, see: http://download.oracle.com/javase/6/docs/technotes/guides/management/agent.html
# On Unix based systems the jmx.password file needs to be owned by the user that will run the server,
# and have permissions set to 0600.
# For details on setting these file permissions on Windows see:
# http://download.oracle.com/javase/1.5.0/docs/guide/management/security-windows.html
wrapper.java.additional=-Dcom.sun.management.jmxremote.port=3637
wrapper.java.additional=-Dcom.sun.management.jmxremote.authenticate=true
wrapper.java.additional=-Dcom.sun.management.jmxremote.ssl=false
wrapper.java.additional=-Dcom.sun.management.jmxremote.password.file=conf/jmx.password
wrapper.java.additional=-Dcom.sun.management.jmxremote.access.file=conf/jmx.access
# Some systems cannot discover host name automatically, and need this line configured:
#wrapper.java.additional=-Djava.rmi.server.hostname=$THE_NEO4J_SERVER_HOSTNAME
# disable UDC (report data to neo4j..)
wrapper.java.additional=-Dneo4j.ext.udc.disable=true
# Uncomment the following lines to enable garbage collection logging
wrapper.java.additional=-Xloggc:data/log/neo4j-gc.log
wrapper.java.additional=-XX:+PrintGCDetails
wrapper.java.additional=-XX:+PrintGCDateStamps
wrapper.java.additional=-XX:+PrintGCApplicationStoppedTime
#wrapper.java.additional=-XX:+PrintPromotionFailure
#wrapper.java.additional=-XX:+PrintTenuringDistribution
# Uncomment the following lines to enable JVM startup diagnostics
#wrapper.java.additional=-XX:+PrintFlagsFinal
#wrapper.java.additional=-XX:+PrintFlagsInitial
# Java Heap Size: by default the Java heap size is dynamically
# calculated based on available system resources.
# Uncomment these lines to set specific initial and maximum
# heap size in MB.
#wrapper.java.initmemory=512
wrapper.java.maxmemory=3072
#********************************************************************
# Wrapper settings
#********************************************************************
# path is relative to the bin dir
wrapper.pidfile=../data/neo4j-server.pid
#********************************************************************
# Wrapper Windows NT/2000/XP Service Properties
#********************************************************************
# WARNING - Do not modify any of these properties when an application
# using this configuration file has been installed as a service.
# Please uninstall the service before modifying this section. The
# service can then be reinstalled.
# Name of the service
wrapper.name=neo4j
默认值：
# Default values for the low-level graph engine
neostore.nodestore.db.mapped_memory=25M
neostore.relationshipstore.db.mapped_memory=120M
neostore.propertystore.db.mapped_memory=90M
neostore.propertystore.db.strings.mapped_memory=100M
neostore.propertystore.db.arrays.mapped_memory=100M
我该怎么办？
编辑：
商店文件大小：
[
{
"description": "Information about the sizes of the different parts of the Neo4j graph store",
"name": "org.neo4j:instance=kernel#0,name=Store file sizes",
"attributes": [
{
"description": "The total disk space used by this Neo4j instance, in bytes.",
"name": "TotalStoreSize",
"value": 401188207,
"isReadable": "true",
"type": "long",
"isWriteable": "false ",
"isIs": "false "
},
{
"description": "The amount of disk space used by the current Neo4j logical log, in bytes.",
"name": "LogicalLogSize",
"value": 24957516,
"isReadable": "true",
"type": "long",
"isWriteable": "false ",
"isIs": "false "
},
{
"description": "The amount of disk space used to store array properties, in bytes.",
"name": "ArrayStoreSize",
"value": 128,
"isReadable": "true",
"type": "long",
"isWriteable": "false ",
"isIs": "false "
},
{
"description": "The amount of disk space used to store nodes, in bytes.",
"name": "NodeStoreSize",
"value": 524160,
"isReadable": "true",
"type": "long",
"isWriteable": "false ",
"isIs": "false "
},
{
"description": "The amount of disk space used to store properties (excluding string values and array values), in bytes.",
"name": "PropertyStoreSize",
"value": 145348280,
"isReadable": "true",
"type": "long",
"isWriteable": "false ",
"isIs": "false "
},
{
"description": "The amount of disk space used to store relationships, in bytes.",
"name": "RelationshipStoreSize",
"value": 114126903,
"isReadable": "true",
"type": "long",
"isWriteable": "false ",
"isIs": "false "
},
{
"description": "The amount of disk space used to store string properties, in bytes.",
"name": "StringStoreSize",
"value": 128,
"isReadable": "true",
"type": "long",
"isWriteable": "false ",
"isIs": "false "
}
],
"url": "org.neo4j/instance%3Dkernel%230%2Cname%3DStore+file+sizes"
}
]
答案 0 :(得分：2)
假设机器中有16 GB的RAM。
首先要设置neostore.xxx.mapped_memory设置以匹配商店文件的大小。我假设他们的总数是5 GB - ＆gt;你剩下11 GB。有关详细信息，请参阅http://docs.neo4j.org/chunked/2.0.4/configuration-caches.html。
为系统保留一些RAM：1GB - ＆gt;你剩下10 GB。
使用wrapper.java.initmemory wrapper.java.maxmemory将剩余的RAM分配给Java堆。将两者都设置为相同的值。
如果将hpc用作cache_type，请考虑根据关系和节点的缓存命中率调整其设置。使用JMX监控它们http://docs.neo4j.org/chunked/2.0.4/jmx-mxbeans.html#jmx-cache-nodecache。
答案 1 :(得分：2)
我们也遇到过这类问题。除了类似于@ stefan-armbruster提到的将Neo4j更新为2.1.2的配置更改之外，我们还将Neo4j配置为使用G1垃圾收集而不是CMS。
自从进行垃圾收集更改以来，我们看到的峰值比以前少得多。
如果您想试一试，可以通过在conf/neo4j-wrapper.conf文件中添加以下内容来启用G1 GC。
wrapper.java.additional=-XX:+UseG1GC
希望结合使用这个和@ stefan-armbruster建议的更改，您将解决问题。