ElasticSearch 内存不足
ElasticSearch Out Of Memory
我有一个基于Symfony2.6的博客（30篇小文章）和运行ning在一个小Ubuntu14.04VPS（4GB内存，50GB磁盘space）上。我使用 ElasticSearch 抛出 FOS ElasticaBundle 以允许 users/readers 在此博客上查找文章（通过关键字和类别，仅此而已）。
近2个月一切顺利，现在博客似乎完全无法访问！
我发现这是由于某种 "OOM" 问题造成的。
我尝试将 indices.fieddata.cache.size 设置为 40%。
我试过看一下head插件。它回答说集群没有连接。
我已经尝试过 /_nodes/stats/indices/fielddata?fields=* 请求。谈到这个节点使用了 5572 字节，这似乎并不多。
当我尝试在终端中使用 Ctrl + C 停止节点时，它花了很长时间，它打印：
[2016-01-04 23:38:37,085][INFO ][node ] [Novs]
stopping ... Exception in thread "elasticsearch[Novs][generic][T#4]"
java.lang.OutOfMemoryError: Java heap space
我还发现我的 elasticsearch1..../data 文件夹非常大，大约 26GB。我很快就会 运行 磁盘 space 不足，不知道是否可以手动删除旧文件夹。
是否有任何简单的命令行工具可以帮助在几秒钟内解决所有这些 OOM 问题？或者类似的东西？
ElasticSearch 配置（我在 /elastiseach-1.7.3/config/ 中找到的唯一配置）：
##################### Elasticsearch Configuration Example
#####################
# This file contains an overview of various configuration settings,
# targeted at operations staff. Application developers should
# consult the guide at <elasticsearch.org/guide>.
#
# The installation procedure is covered at
# <elasticsearch.org/guide/en/elasticsearch/reference/current/setup.html>.
#
# Elasticsearch comes with reasonable defaults for most settings,
# so you can try it out without bothering with configuration.
#
# Most of the time, these defaults are just fine for running a production
# cluster. If you're fine-tuning your cluster, or wondering about the
# effect of certain configuration option, please _do ask_ on the
# mailing list or IRC channel [elasticsearch.org/community].
# Any element in the configuration can be replaced with environment variables
# by placing them in ${...} notation. For example:
#
#node.rack: ${RACK_ENV_VAR}
# For information on supported formats and syntax for the config file, see
# <elasticsearch.org/guide/en/elasticsearch/reference/current/setup-configuration.html>
################################### Cluster ###################################
# Cluster name identifies your cluster for auto-discovery. If you're running
# multiple clusters on the same network, make sure you're using unique names.
#
#cluster.name: elasticsearch
#################################### Node #####################################
# Node names are generated dynamically on startup, so you're relieved
# from configuring them manually. You can tie this node to a specific name:
#
#node.name: "Franz Kafka"
# Every node can be configured to allow or deny being eligible as the master,
# and to allow or deny to store the data.
#
# Allow this node to be eligible as a master node (enabled by default):
#
#node.master: true
#
# Allow this node to store data (enabled by default):
#
#node.data: true
# You can exploit these settings to design advanced cluster topologies.
#
# 1. You want this node to never become a master node, only to hold data.
# This will be the "workhorse" of your cluster.
#
#node.master: false
#node.data: true
#
# 2. You want this node to only serve as a master: to not store any data and
# to have free resources. This will be the "coordinator" of your cluster.
#
#node.master: true
#node.data: false
#
# 3. You want this node to be neither master nor data node, but
# to act as a "search load balancer" (fetching data from nodes,
# aggregating results, etc.)
#
#node.master: false
#node.data: false
# Use the Cluster Health API [localhost:9200/_cluster/health], the
# Node Info API [localhost:9200/_nodes] or GUI tools
# such as <http://www.elasticsearch.org/overview/marvel/>,
# <github.com/karmi/elasticsearch-paramedic>,
# <github.com/lukas-vlcek/bigdesk> and
# mobz.github.com/elasticsearch-head> to inspect the cluster state.
# A node can have generic attributes associated with it, which can later be used
# for customized shard allocation filtering, or allocation awareness. An attribute
# is a simple key value pair, similar to node.key: value, here is an example:
#
#node.rack: rack314
# By default, multiple nodes are allowed to start from the same installation location
# to disable it, set the following:
#node.max_local_storage_nodes: 1
#################################### Index ####################################
# You can set a number of options (such as shard/replica options, mapping
# or analyzer definitions, translog settings, ...) for indices globally,
# in this file.
#
# Note, that it makes more sense to configure index settings specifically for
# a certain index, either when creating it or by using the index templates API.
#
# See <elasticsearch.org/guide/en/elasticsearch/reference/current/index-modules.html> and
# <elasticsearch.org/guide/en/elasticsearch/reference/current/indices-create-index.html>
# for more information.
# Set the number of shards (splits) of an index (5 by default):
#
#index.number_of_shards: 5
# Set the number of replicas (additional copies) of an index (1 by default):
#
#index.number_of_replicas: 1
# Note, that for development on a local machine, with small indices, it usually
# makes sense to "disable" the distributed features:
#
#index.number_of_shards: 1
#index.number_of_replicas: 0
# These settings directly affect the performance of index and search operations
# in your cluster. Assuming you have enough machines to hold shards and
# replicas, the rule of thumb is:
#
# 1. Having more *shards* enhances the _indexing_ performance and allows to
# _distribute_ a big index across machines.
# 2. Having more *replicas* enhances the _search_ performance and improves the
# cluster _availability_.
#
# The "number_of_shards" is a one-time setting for an index.
#
# The "number_of_replicas" can be increased or decreased anytime,
# by using the Index Update Settings API.
#
# Elasticsearch takes care about load balancing, relocating, gathering the
# results from nodes, etc. Experiment with different settings to fine-tune
# your setup.
# Use the Index Status API (<localhost:9200/A/_status>) to inspect
# the index status.
#################################### Paths ####################################
# Path to directory containing configuration (this file and logging.yml):
#
#path.conf: /path/to/conf
# Path to directory where to store index data allocated for this node.
#
#path.data: /path/to/data
#
# Can optionally include more than one location, causing data to be striped across
# the locations (a la RAID 0) on a file level, favouring locations with most free
# space on creation. For example:
#
#path.data: /path/to/data1,/path/to/data2
# Path to temporary files:
#
#path.work: /path/to/work
# Path to log files:
#
#path.logs: /path/to/logs
# Path to where plugins are installed:
#
#path.plugins: /path/to/plugins
#################################### Plugin ###################################
# If a plugin listed here is not installed for current node, the node will not start.
#
#plugin.mandatory: mapper-attachments,lang-groovy
################################### Memory ####################################
# Elasticsearch performs poorly when JVM starts swapping: you should ensure that
# it _never_ swaps.
#
# Set this property to true to lock the memory:
#
#bootstrap.mlockall: true
# Make sure that the ES_MIN_MEM and ES_MAX_MEM environment variables are set
# to the same value, and that the machine has enough memory to allocate
# for Elasticsearch, leaving enough memory for the operating system itself.
#
# You should also make sure that the Elasticsearch process is allowed to lock
# the memory, eg. by using `ulimit -l unlimited`.
############################## Network And HTTP ###############################
# Elasticsearch, by default, binds itself to the 0.0.0.0 address, and listens
# on port [9200-9300] for HTTP traffic and on port [9300-9400] for node-to-node
# communication. (the range means that if the port is busy, it will automatically
# try the next port).
# Set the bind address specifically (IPv4 or IPv6):
#
#network.bind_host: 192.168.0.1
# Set the address other nodes will use to communicate with this node. If not
# set, it is automatically derived. It must point to an actual IP address.
#
#network.publish_host: 192.168.0.1
# Set both 'bind_host' and 'publish_host':
#
#network.host: 192.168.0.1
# Set a custom port for the node to node communication (9300 by default):
#
#transport.tcp.port: 9300
# Enable compression for all communication between nodes (disabled by default):
#
#transport.tcp.compress: true
# Set a custom port to listen for HTTP traffic:
#
#http.port: 9200
# Set a custom allowed content length:
#
#http.max_content_length: 100mb
# Disable HTTP completely:
#
#http.enabled: false
################################### Gateway ###################################
# The gateway allows for persisting the cluster state between full cluster
# restarts. Every change to the state (such as adding an index) will be stored
# in the gateway, and when the cluster starts up for the first time,
# it will read its state from the gateway.
# There are several types of gateway implementations. For more information, see
# <elasticsearch.org/guide/en/elasticsearch/reference/current/modules-gateway.html>.
# The default gateway type is the "local" gateway (recommended):
#
#gateway.type: local
# Settings below control how and when to start the initial recovery process on
# a full cluster restart (to reuse as much local data as possible when using shared
# gateway).
# Allow recovery process after N nodes in a cluster are up:
#
#gateway.recover_after_nodes: 1
# Set the timeout to initiate the recovery process, once the N nodes
# from previous setting are up (accepts time value):
#
#gateway.recover_after_time: 5m
# Set how many nodes are expected in this cluster. Once these N nodes
# are up (and recover_after_nodes is met), begin recovery process immediately
# (without waiting for recover_after_time to expire):
#
#gateway.expected_nodes: 2
############################# Recovery Throttling #############################
# These settings allow to control the process of shards allocation between
# nodes during initial recovery, replica allocation, rebalancing,
# or when adding and removing nodes.
# Set the number of concurrent recoveries happening on a node:
#
# 1. During the initial recovery
#
#cluster.routing.allocation.node_initial_primaries_recoveries: 4
#
# 2. During adding/removing nodes, rebalancing, etc
#
#cluster.routing.allocation.node_concurrent_recoveries: 2
# Set to throttle throughput when recovering (eg. 100mb, by default 20mb):
#
#indices.recovery.max_bytes_per_sec: 20mb
# Set to limit the number of open concurrent streams when
# recovering a shard from a peer:
#
#indices.recovery.concurrent_streams: 5
################################## Discovery ##################################
# Discovery infrastructure ensures nodes can be found within a cluster
# and master node is elected. Multicast discovery is the default.
# Set to ensure a node sees N other master eligible nodes to be considered
# operational within the cluster. This should be set to a quorum/majority of
# the master-eligible nodes in the cluster.
#
#discovery.zen.minimum_master_nodes: 1
# Set the time to wait for ping responses from other nodes when discovering.
# Set this option to a higher value on a slow or congested network
# to minimize discovery failures:
#
#discovery.zen.ping.timeout: 3s
# For more information, see
# <elasticsearch.org/guide/en/elasticsearch/reference/current/modules-discovery-zen.html>
# Unicast discovery allows to explicitly control which nodes will be used
# to discover the cluster. It can be used when multicast is not present,
# or to restrict the cluster communication-wise.
#
# 1. Disable multicast discovery (enabled by default):
#
#discovery.zen.ping.multicast.enabled: false
#
# 2. Configure an initial list of master nodes in the cluster
# to perform discovery when new nodes (master or data) are started:
#
#discovery.zen.ping.unicast.hosts: ["host1", "host2:port"]
# EC2 discovery allows to use AWS EC2 API in order to perform discovery.
#
# You have to install the cloud-aws plugin for enabling the EC2 discovery.
#
# For more information, see
# <elasticsearch.org/guide/en/elasticsearch/reference/current/modules-discovery-ec2.html>
#
# See <http://elasticsearch.org/tutorials/elasticsearch-on-ec2/>
# for a step-by-step tutorial.
# GCE discovery allows to use Google Compute Engine API in order to perform discovery.
#
# You have to install the cloud-gce plugin for enabling the GCE discovery.
#
# For more information, see <github.com/elasticsearch/elasticsearch-cloud-gce>.
# Azure discovery allows to use Azure API in order to perform discovery.
#
# You have to install the cloud-azure plugin for enabling the Azure discovery.
#
# For more information, see <github.com/elasticsearch/elasticsearch-cloud-azure>.
################################## Slow Log ##################################
# Shard level query and fetch threshold logging.
#index.search.slowlog.threshold.query.warn: 10s
#index.search.slowlog.threshold.query.info: 5s
#index.search.slowlog.threshold.query.debug: 2s
#index.search.slowlog.threshold.query.trace: 500ms
#index.search.slowlog.threshold.fetch.warn: 1s
#index.search.slowlog.threshold.fetch.info: 800ms
#index.search.slowlog.threshold.fetch.debug: 500ms
#index.search.slowlog.threshold.fetch.trace: 200ms
#index.indexing.slowlog.threshold.index.warn: 10s
#index.indexing.slowlog.threshold.index.info: 5s
#index.indexing.slowlog.threshold.index.debug: 2s
#index.indexing.slowlog.threshold.index.trace: 500ms
################################## GC Logging ################################
#monitor.jvm.gc.young.warn: 1000ms
#monitor.jvm.gc.young.info: 700ms
#monitor.jvm.gc.young.debug: 400ms
#monitor.jvm.gc.old.warn: 10s
#monitor.jvm.gc.old.info: 5s
#monitor.jvm.gc.old.debug: 2s
################################## Security ################################
# Uncomment if you want to enable JSONP as a valid return transport on the
# http server. With this enabled, it may pose a security risk, so disabling
# it unless you need it is recommended (it is disabled by default).
#
#http.jsonp.enable: true
在此先感谢您的帮助。
这似乎是 Heap Space 问题，请确保您有足够的内存。阅读 this blog 关于堆大小调整的内容。
因为你有 4GB RAM，所以将其中一半分配给 Elasticsearch 堆。 运行export ES_HEAP_SIZE=2g。同时为 JVM 锁定内存，在配置文件中取消注释 bootstrap.mlockall: true。
另外一个重要的事情是，如果你只有 30 篇小文章，你的 data folder 26GB 大小如何？你有多少个索引，运行 GET _cat/indices 检查哪个索引占用了那么多 space。 运行 GET /_nodes/stats 查看有关节点的详细信息，您可能能够找出问题所在。还有一件事，如果您使用 marvel plugin，那么 marvel indices 会非常大，您需要删除它们以释放磁盘 space。
调整indices.fieddata.cache.size 不是内存不足的解决方案。来自 Docs
This setting is a safeguard, not a solution for insufficient memory.
If you don’t have enough memory to keep your fielddata resident in
memory, Elasticsearch will constantly have to reload data from disk,
and evict other data to make space. Evictions cause heavy disk I/O and
generate a large amount of garbage in memory, which must be garbage
collected later on.
希望对您有所帮助！！
我有一个基于Symfony2.6的博客（30篇小文章）和运行ning在一个小Ubuntu14.04VPS（4GB内存，50GB磁盘space）上。我使用 ElasticSearch 抛出 FOS ElasticaBundle 以允许 users/readers 在此博客上查找文章（通过关键字和类别，仅此而已）。
近2个月一切顺利，现在博客似乎完全无法访问！
我发现这是由于某种 "OOM" 问题造成的。
我尝试将 indices.fieddata.cache.size 设置为 40%。
我试过看一下head插件。它回答说集群没有连接。
我已经尝试过 /_nodes/stats/indices/fielddata?fields=* 请求。谈到这个节点使用了 5572 字节，这似乎并不多。
当我尝试在终端中使用 Ctrl + C 停止节点时，它花了很长时间，它打印：
[2016-01-04 23:38:37,085][INFO ][node ] [Novs] stopping ... Exception in thread "elasticsearch[Novs][generic][T#4]" java.lang.OutOfMemoryError: Java heap space
我还发现我的 elasticsearch1..../data 文件夹非常大，大约 26GB。我很快就会 运行 磁盘 space 不足，不知道是否可以手动删除旧文件夹。
是否有任何简单的命令行工具可以帮助在几秒钟内解决所有这些 OOM 问题？或者类似的东西？
ElasticSearch 配置（我在 /elastiseach-1.7.3/config/ 中找到的唯一配置）：
##################### Elasticsearch Configuration Example
#####################
# This file contains an overview of various configuration settings,
# targeted at operations staff. Application developers should
# consult the guide at <elasticsearch.org/guide>.
#
# The installation procedure is covered at
# <elasticsearch.org/guide/en/elasticsearch/reference/current/setup.html>.
#
# Elasticsearch comes with reasonable defaults for most settings,
# so you can try it out without bothering with configuration.
#
# Most of the time, these defaults are just fine for running a production
# cluster. If you're fine-tuning your cluster, or wondering about the
# effect of certain configuration option, please _do ask_ on the
# mailing list or IRC channel [elasticsearch.org/community].
# Any element in the configuration can be replaced with environment variables
# by placing them in ${...} notation. For example:
#
#node.rack: ${RACK_ENV_VAR}
# For information on supported formats and syntax for the config file, see
# <elasticsearch.org/guide/en/elasticsearch/reference/current/setup-configuration.html>
################################### Cluster ###################################
# Cluster name identifies your cluster for auto-discovery. If you're running
# multiple clusters on the same network, make sure you're using unique names.
#
#cluster.name: elasticsearch
#################################### Node #####################################
# Node names are generated dynamically on startup, so you're relieved
# from configuring them manually. You can tie this node to a specific name:
#
#node.name: "Franz Kafka"
# Every node can be configured to allow or deny being eligible as the master,
# and to allow or deny to store the data.
#
# Allow this node to be eligible as a master node (enabled by default):
#
#node.master: true
#
# Allow this node to store data (enabled by default):
#
#node.data: true
# You can exploit these settings to design advanced cluster topologies.
#
# 1. You want this node to never become a master node, only to hold data.
# This will be the "workhorse" of your cluster.
#
#node.master: false
#node.data: true
#
# 2. You want this node to only serve as a master: to not store any data and
# to have free resources. This will be the "coordinator" of your cluster.
#
#node.master: true
#node.data: false
#
# 3. You want this node to be neither master nor data node, but
# to act as a "search load balancer" (fetching data from nodes,
# aggregating results, etc.)
#
#node.master: false
#node.data: false
# Use the Cluster Health API [localhost:9200/_cluster/health], the
# Node Info API [localhost:9200/_nodes] or GUI tools
# such as <http://www.elasticsearch.org/overview/marvel/>,
# <github.com/karmi/elasticsearch-paramedic>,
# <github.com/lukas-vlcek/bigdesk> and
# mobz.github.com/elasticsearch-head> to inspect the cluster state.
# A node can have generic attributes associated with it, which can later be used
# for customized shard allocation filtering, or allocation awareness. An attribute
# is a simple key value pair, similar to node.key: value, here is an example:
#
#node.rack: rack314
# By default, multiple nodes are allowed to start from the same installation location
# to disable it, set the following:
#node.max_local_storage_nodes: 1
#################################### Index ####################################
# You can set a number of options (such as shard/replica options, mapping
# or analyzer definitions, translog settings, ...) for indices globally,
# in this file.
#
# Note, that it makes more sense to configure index settings specifically for
# a certain index, either when creating it or by using the index templates API.
#
# See <elasticsearch.org/guide/en/elasticsearch/reference/current/index-modules.html> and
# <elasticsearch.org/guide/en/elasticsearch/reference/current/indices-create-index.html>
# for more information.
# Set the number of shards (splits) of an index (5 by default):
#
#index.number_of_shards: 5
# Set the number of replicas (additional copies) of an index (1 by default):
#
#index.number_of_replicas: 1
# Note, that for development on a local machine, with small indices, it usually
# makes sense to "disable" the distributed features:
#
#index.number_of_shards: 1
#index.number_of_replicas: 0
# These settings directly affect the performance of index and search operations
# in your cluster. Assuming you have enough machines to hold shards and
# replicas, the rule of thumb is:
#
# 1. Having more *shards* enhances the _indexing_ performance and allows to
# _distribute_ a big index across machines.
# 2. Having more *replicas* enhances the _search_ performance and improves the
# cluster _availability_.
#
# The "number_of_shards" is a one-time setting for an index.
#
# The "number_of_replicas" can be increased or decreased anytime,
# by using the Index Update Settings API.
#
# Elasticsearch takes care about load balancing, relocating, gathering the
# results from nodes, etc. Experiment with different settings to fine-tune
# your setup.
# Use the Index Status API (<localhost:9200/A/_status>) to inspect
# the index status.
#################################### Paths ####################################
# Path to directory containing configuration (this file and logging.yml):
#
#path.conf: /path/to/conf
# Path to directory where to store index data allocated for this node.
#
#path.data: /path/to/data
#
# Can optionally include more than one location, causing data to be striped across
# the locations (a la RAID 0) on a file level, favouring locations with most free
# space on creation. For example:
#
#path.data: /path/to/data1,/path/to/data2
# Path to temporary files:
#
#path.work: /path/to/work
# Path to log files:
#
#path.logs: /path/to/logs
# Path to where plugins are installed:
#
#path.plugins: /path/to/plugins
#################################### Plugin ###################################
# If a plugin listed here is not installed for current node, the node will not start.
#
#plugin.mandatory: mapper-attachments,lang-groovy
################################### Memory ####################################
# Elasticsearch performs poorly when JVM starts swapping: you should ensure that
# it _never_ swaps.
#
# Set this property to true to lock the memory:
#
#bootstrap.mlockall: true
# Make sure that the ES_MIN_MEM and ES_MAX_MEM environment variables are set
# to the same value, and that the machine has enough memory to allocate
# for Elasticsearch, leaving enough memory for the operating system itself.
#
# You should also make sure that the Elasticsearch process is allowed to lock
# the memory, eg. by using `ulimit -l unlimited`.
############################## Network And HTTP ###############################
# Elasticsearch, by default, binds itself to the 0.0.0.0 address, and listens
# on port [9200-9300] for HTTP traffic and on port [9300-9400] for node-to-node
# communication. (the range means that if the port is busy, it will automatically
# try the next port).
# Set the bind address specifically (IPv4 or IPv6):
#
#network.bind_host: 192.168.0.1
# Set the address other nodes will use to communicate with this node. If not
# set, it is automatically derived. It must point to an actual IP address.
#
#network.publish_host: 192.168.0.1
# Set both 'bind_host' and 'publish_host':
#
#network.host: 192.168.0.1
# Set a custom port for the node to node communication (9300 by default):
#
#transport.tcp.port: 9300
# Enable compression for all communication between nodes (disabled by default):
#
#transport.tcp.compress: true
# Set a custom port to listen for HTTP traffic:
#
#http.port: 9200
# Set a custom allowed content length:
#
#http.max_content_length: 100mb
# Disable HTTP completely:
#
#http.enabled: false
################################### Gateway ###################################
# The gateway allows for persisting the cluster state between full cluster
# restarts. Every change to the state (such as adding an index) will be stored
# in the gateway, and when the cluster starts up for the first time,
# it will read its state from the gateway.
# There are several types of gateway implementations. For more information, see
# <elasticsearch.org/guide/en/elasticsearch/reference/current/modules-gateway.html>.
# The default gateway type is the "local" gateway (recommended):
#
#gateway.type: local
# Settings below control how and when to start the initial recovery process on
# a full cluster restart (to reuse as much local data as possible when using shared
# gateway).
# Allow recovery process after N nodes in a cluster are up:
#
#gateway.recover_after_nodes: 1
# Set the timeout to initiate the recovery process, once the N nodes
# from previous setting are up (accepts time value):
#
#gateway.recover_after_time: 5m
# Set how many nodes are expected in this cluster. Once these N nodes
# are up (and recover_after_nodes is met), begin recovery process immediately
# (without waiting for recover_after_time to expire):
#
#gateway.expected_nodes: 2
############################# Recovery Throttling #############################
# These settings allow to control the process of shards allocation between
# nodes during initial recovery, replica allocation, rebalancing,
# or when adding and removing nodes.
# Set the number of concurrent recoveries happening on a node:
#
# 1. During the initial recovery
#
#cluster.routing.allocation.node_initial_primaries_recoveries: 4
#
# 2. During adding/removing nodes, rebalancing, etc
#
#cluster.routing.allocation.node_concurrent_recoveries: 2
# Set to throttle throughput when recovering (eg. 100mb, by default 20mb):
#
#indices.recovery.max_bytes_per_sec: 20mb
# Set to limit the number of open concurrent streams when
# recovering a shard from a peer:
#
#indices.recovery.concurrent_streams: 5
################################## Discovery ##################################
# Discovery infrastructure ensures nodes can be found within a cluster
# and master node is elected. Multicast discovery is the default.
# Set to ensure a node sees N other master eligible nodes to be considered
# operational within the cluster. This should be set to a quorum/majority of
# the master-eligible nodes in the cluster.
#
#discovery.zen.minimum_master_nodes: 1
# Set the time to wait for ping responses from other nodes when discovering.
# Set this option to a higher value on a slow or congested network
# to minimize discovery failures:
#
#discovery.zen.ping.timeout: 3s
# For more information, see
# <elasticsearch.org/guide/en/elasticsearch/reference/current/modules-discovery-zen.html>
# Unicast discovery allows to explicitly control which nodes will be used
# to discover the cluster. It can be used when multicast is not present,
# or to restrict the cluster communication-wise.
#
# 1. Disable multicast discovery (enabled by default):
#
#discovery.zen.ping.multicast.enabled: false
#
# 2. Configure an initial list of master nodes in the cluster
# to perform discovery when new nodes (master or data) are started:
#
#discovery.zen.ping.unicast.hosts: ["host1", "host2:port"]
# EC2 discovery allows to use AWS EC2 API in order to perform discovery.
#
# You have to install the cloud-aws plugin for enabling the EC2 discovery.
#
# For more information, see
# <elasticsearch.org/guide/en/elasticsearch/reference/current/modules-discovery-ec2.html>
#
# See <http://elasticsearch.org/tutorials/elasticsearch-on-ec2/>
# for a step-by-step tutorial.
# GCE discovery allows to use Google Compute Engine API in order to perform discovery.
#
# You have to install the cloud-gce plugin for enabling the GCE discovery.
#
# For more information, see <github.com/elasticsearch/elasticsearch-cloud-gce>.
# Azure discovery allows to use Azure API in order to perform discovery.
#
# You have to install the cloud-azure plugin for enabling the Azure discovery.
#
# For more information, see <github.com/elasticsearch/elasticsearch-cloud-azure>.
################################## Slow Log ##################################
# Shard level query and fetch threshold logging.
#index.search.slowlog.threshold.query.warn: 10s
#index.search.slowlog.threshold.query.info: 5s
#index.search.slowlog.threshold.query.debug: 2s
#index.search.slowlog.threshold.query.trace: 500ms
#index.search.slowlog.threshold.fetch.warn: 1s
#index.search.slowlog.threshold.fetch.info: 800ms
#index.search.slowlog.threshold.fetch.debug: 500ms
#index.search.slowlog.threshold.fetch.trace: 200ms
#index.indexing.slowlog.threshold.index.warn: 10s
#index.indexing.slowlog.threshold.index.info: 5s
#index.indexing.slowlog.threshold.index.debug: 2s
#index.indexing.slowlog.threshold.index.trace: 500ms
################################## GC Logging ################################
#monitor.jvm.gc.young.warn: 1000ms
#monitor.jvm.gc.young.info: 700ms
#monitor.jvm.gc.young.debug: 400ms
#monitor.jvm.gc.old.warn: 10s
#monitor.jvm.gc.old.info: 5s
#monitor.jvm.gc.old.debug: 2s
################################## Security ################################
# Uncomment if you want to enable JSONP as a valid return transport on the
# http server. With this enabled, it may pose a security risk, so disabling
# it unless you need it is recommended (it is disabled by default).
#
#http.jsonp.enable: true
在此先感谢您的帮助。
这似乎是 Heap Space 问题，请确保您有足够的内存。阅读 this blog 关于堆大小调整的内容。
因为你有 4GB RAM，所以将其中一半分配给 Elasticsearch 堆。 运行export ES_HEAP_SIZE=2g。同时为 JVM 锁定内存，在配置文件中取消注释 bootstrap.mlockall: true。
另外一个重要的事情是，如果你只有 30 篇小文章，你的 data folder 26GB 大小如何？你有多少个索引，运行 GET _cat/indices 检查哪个索引占用了那么多 space。 运行 GET /_nodes/stats 查看有关节点的详细信息，您可能能够找出问题所在。还有一件事，如果您使用 marvel plugin，那么 marvel indices 会非常大，您需要删除它们以释放磁盘 space。
调整indices.fieddata.cache.size 不是内存不足的解决方案。来自 Docs
This setting is a safeguard, not a solution for insufficient memory.
If you don’t have enough memory to keep your fielddata resident in memory, Elasticsearch will constantly have to reload data from disk, and evict other data to make space. Evictions cause heavy disk I/O and generate a large amount of garbage in memory, which must be garbage collected later on.
希望对您有所帮助！！