# 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.

# see kafka.server.KafkaConfig for additional details and defaults

############################# Server Basics #############################

# The id of the broker. This must be set to a unique integer for each broker.

# 节点的ID，必须与其它节点不同

broker.id=0

############################# Socket Server Settings #############################

listeners=PLAINTEXT://:9092

# The port the socket server listens on

# 监听端口

#port=9092

# Hostname the broker will bind to. If not set, the server will bind to all interfaces

# 节点需要绑定的主机名称。如果没有设置，服务器会绑定到所有接口

#host.name=localhost

# Hostname the broker will advertise to producers and consumers. If not set, it uses the

# value for "host.name" if configured.  Otherwise, it will use the value returned from

# java.net.InetAddress.getCanonicalHostName().

# 节点的主机名会通知给生产者和消费者。如果没有设置，它将会使用"host.name"的值（前提是设置了host.name）。

# 否则他会使用java.net.InetAddress.getCanonicalHostName()的返回值

#advertised.host.name=<hostname routable by clients>

# The port to publish to ZooKeeper for clients to use. If this is not set,

# it will publish the same port that the broker binds to.

# 这个端口将暴露给Zookeeper以供客户端来使用。如果没有设置，将会暴露节点绑定的端口

#advertised.port=<port accessible by clients>

# The number of threads handling network requests

# 接受网络请求的线程数

num.network.threads=3

# The number of threads doing disk I/O、

# 进行磁盘IO的线程数

num.io.threads=8

# The send buffer (SO_SNDBUF) used by the socket server

# 套接字服务器使用的发送缓冲区大小

socket.send.buffer.bytes=102400

# The receive buffer (SO_RCVBUF) used by the socket server

# 套接字服务器使用的接收缓冲区大小

socket.receive.buffer.bytes=102400

# The maximum size of a request that the socket server will accept (protection against OOM)

# 单个请求最大能接收的数据量

socket.request.max.bytes=104857600

############################# Log Basics #############################

# A comma seperated list of directories under which to store log files

# 一个逗号分隔的目录列表，用来存储日志文件

log.dirs=/tmp/kafka-logs

# The default number of log partitions per topic. More partitions allow greater

# parallelism for consumption, but this will also result in more files across

# the brokers.

# 每个主题的日志分区的默认数量。更多的分区允许更大的并行操作，但是它会导致节点产生更多的文件

num.partitions=1

# The number of threads per data directory to be used for log recovery at startup and flushing at shutdown.

# This value is recommended to be increased for installations with data dirs located in RAID array.

# 每个数据目录中的线程数，用于在启动时日志恢复，并在关闭时刷新。

num.recovery.threads.per.data.dir=1

############################# Log Flush Policy #############################

# Messages are immediately written to the filesystem but by default we only fsync() to sync

# the OS cache lazily. The following configurations control the flush of data to disk.

# 消息直接被写入文件系统，但是默认情况下我们仅仅调用fsync()以延迟的同步系统缓存

# There are a few important trade-offs here:

# 这些有一些重要的权衡

#    1. Durability: Unflushed data may be lost if you are not using replication.

#    2. Latency: Very large flush intervals may lead to latency spikes when the flush does occur as there will be a lot of data to flush.

#    3. Throughput: The flush is generally the most expensive operation, and a small flush interval may lead to exceessive seeks.

#    1. 持久性:如果不使用复制，未刷新的数据可能会丢失。

#    2. 延迟:非常大的刷新间隔可能会在刷新时导致延迟，因为将会有大量数据刷新。

#    3. 吞吐量:刷新通常是最昂贵的操作，而一个小的刷新间隔可能会导致过多的搜索。

# The settings below allow one to configure the flush policy to flush data after a period of time or

# every N messages (or both). This can be done globally and overridden on a per-topic basis.

# 下面的设置允许你去配置刷新策略，每隔一段时间刷新或者一次N个消息（或者两个都配置）。这可以在全局范围内完成，并在每个主题的基础上重写。

# The number of messages to accept before forcing a flush of data to disk

# 在强制刷新数据到磁盘执勤啊允许接收消息的数量

#log.flush.interval.messages=10000

# The maximum amount of time a message can sit in a log before we force a flush

# 在强制刷新之前，消息可以在日志中停留的最长时间

#log.flush.interval.ms=1000

############################# Log Retention Policy #############################

# The following configurations control the disposal of log segments. The policy can

# be set to delete segments after a period of time, or after a given size has accumulated.

# 以下的配置控制了日志段的处理。策略可以配置为每隔一段时间删除片段或者到达一定大小之后。

# A segment will be deleted whenever *either* of these criteria are met. Deletion always happens

# from the end of the log.

# 当满足这些条件时，将会删除一个片段。删除总是发生在日志的末尾。

# The minimum age of a log file to be eligible for deletion

# 一个日志的最小存活时间，可以被删除

log.retention.hours=168

# A size-based retention policy for logs. Segments are pruned from the log as long as the remaining

# segments don't drop below log.retention.bytes.

# 一个基于大小的日志保留策略。段将被从日志中删除只要剩下的部分段不低于log.retention.bytes。

#log.retention.bytes=1073741824

# The maximum size of a log segment file. When this size is reached a new log segment will be created.

# 每一个日志段大小的最大值。当到达这个大小时，会生成一个新的片段。

log.segment.bytes=1073741824

# The interval at which log segments are checked to see if they can be deleted according

# to the retention policies

# 检查日志段的时间间隔，看是否可以根据保留策略删除它们

log.retention.check.interval.ms=300000

############################# Zookeeper #############################

# Zookeeper connection string (see zookeeper docs for details).

# Zookeeper连接字符串（具体见Zookeeper文档）

# This is a comma separated host:port pairs, each corresponding to a zk

# 这是一个以逗号为分割的部分，每一个都匹配一个Zookeeper

# server. e.g. "127.0.0.1:3000,127.0.0.1:3001,127.0.0.1:3002".

# You can also append an optional chroot string to the urls to specify the

# root directory for all kafka znodes.

# 您还可以将一个可选的chroot字符串附加到url，以指定所有kafka znode的根目录。

zookeeper.connect=localhost:2181

# Timeout in ms for connecting to zookeeper

# 连接到Zookeeper的超时时间

zookeeper.connection.timeout.ms=6000

# 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.

# see kafka.server.KafkaConfig for additional details and defaults

############################# Server Basics #############################

# The id of the broker. This must be set to a unique integer for each broker.

# 节点的ID，必须与其它节点不同

broker.id=0

# Switch to enable topic deletion or not, default value is false

# 选择启用删除主题功能，默认false

#delete.topic.enable=true

############################# Socket Server Settings #############################

# The address the socket server listens on. It will get the value returned from

# java.net.InetAddress.getCanonicalHostName() if not configured.

# 套接字服务器坚挺的地址。如果没有配置，就使用java.net.InetAddress.getCanonicalHostName()的返回值

#   FORMAT:格式：

#     listeners = security_protocol://host_name:port

#   EXAMPLE:例子：

#     listeners = PLAINTEXT://your.host.name:9092

#listeners=PLAINTEXT://:9092

# Hostname and port the broker will advertise to producers and consumers. If not set,

# it uses the value for "listeners" if configured.  Otherwise, it will use the value

# returned from java.net.InetAddress.getCanonicalHostName().

# 节点的主机名会通知给生产者和消费者。如果没有设置，如果配置了"listeners"就使用"listeners"的值。

# 否则就使用java.net.InetAddress.getCanonicalHostName()的返回值

#advertised.listeners=PLAINTEXT://your.host.name:9092

# The number of threads handling network requests

# 接受网络请求的线程数

num.network.threads=3

# The number of threads doing disk I/O

# 进行磁盘IO的线程数

num.io.threads=8

# The send buffer (SO_SNDBUF) used by the socket server

# 套接字服务器使用的发送缓冲区大小

socket.send.buffer.bytes=102400

# The receive buffer (SO_RCVBUF) used by the socket server

# 套接字服务器使用的接收缓冲区大小

socket.receive.buffer.bytes=102400

# The maximum size of a request that the socket server will accept (protection against OOM)

# 单个请求最大能接收的数据量

socket.request.max.bytes=104857600

############################# Log Basics #############################

# A comma seperated list of directories under which to store log files

# 一个逗号分隔的目录列表，用来存储日志文件

log.dirs=/tmp/kafka-logs

# The default number of log partitions per topic. More partitions allow greater

# parallelism for consumption, but this will also result in more files across

# the brokers.

# 每个主题的日志分区的默认数量。更多的分区允许更大的并行操作，但是它会导致节点产生更多的文件

num.partitions=1

# The number of threads per data directory to be used for log recovery at startup and flushing at shutdown.

# This value is recommended to be increased for installations with data dirs located in RAID array.

# 每个数据目录中的线程数，用于在启动时日志恢复，并在关闭时刷新。

num.recovery.threads.per.data.dir=1

############################# Log Flush Policy #############################

# Messages are immediately written to the filesystem but by default we only fsync() to sync

# the OS cache lazily. The following configurations control the flush of data to disk.

# 消息直接被写入文件系统，但是默认情况下我们仅仅调用fsync()以延迟的同步系统缓存

# There are a few important trade-offs here:

# 这些有一些重要的权衡

#    1. Durability: Unflushed data may be lost if you are not using replication.

#    2. Latency: Very large flush intervals may lead to latency spikes when the flush does occur as there will be a lot of data to flush.

#    3. Throughput: The flush is generally the most expensive operation, and a small flush interval may lead to exceessive seeks.

#    1. 持久性:如果不使用复制，未刷新的数据可能会丢失。

#    2. 延迟:非常大的刷新间隔可能会在刷新时导致延迟，因为将会有大量数据刷新。

#    3. 吞吐量:刷新通常是最昂贵的操作，而一个小的刷新间隔可能会导致过多的搜索。

# The settings below allow one to configure the flush policy to flush data after a period of time or

# every N messages (or both). This can be done globally and overridden on a per-topic basis.

# 下面的设置允许你去配置刷新策略，每隔一段时间刷新或者一次N个消息（或者两个都配置）。这可以在全局范围内完成，并在每个主题的基础上重写。

# The number of messages to accept before forcing a flush of data to disk

# 在强制刷新数据到磁盘之前允许接收消息的数量

#log.flush.interval.messages=10000

# The maximum amount of time a message can sit in a log before we force a flush

# 在强制刷新之前，消息可以在日志中停留的最长时间

#log.flush.interval.ms=1000

############################# Log Retention Policy #############################

# The following configurations control the disposal of log segments. The policy can

# be set to delete segments after a period of time, or after a given size has accumulated.

# 以下的配置控制了日志段的处理。策略可以配置为每隔一段时间删除片段或者到达一定大小之后。

# A segment will be deleted whenever *either* of these criteria are met. Deletion always happens

# from the end of the log.

# 当满足这些条件时，将会删除一个片段。删除总是发生在日志的末尾。

# The minimum age of a log file to be eligible for deletion

# 一个日志的最小存活时间，可以被删除

log.retention.hours=168

# A size-based retention policy for logs. Segments are pruned from the log as long as the remaining

# segments don't drop below log.retention.bytes.

# 一个基于大小的日志保留策略。段将被从日志中删除只要剩下的部分段不低于log.retention.bytes。

#log.retention.bytes=1073741824

# The maximum size of a log segment file. When this size is reached a new log segment will be created.

# 每一个日志段大小的最大值。当到达这个大小时，会生成一个新的片段。

log.segment.bytes=1073741824

# The interval at which log segments are checked to see if they can be deleted according

# to the retention policies

# 检查日志段的时间间隔，看是否可以根据保留策略删除它们

log.retention.check.interval.ms=300000

############################# Zookeeper #############################

# Zookeeper connection string (see zookeeper docs for details).

# Zookeeper连接字符串（具体见Zookeeper文档）

# This is a comma separated host:port pairs, each corresponding to a zk

# 这是一个以逗号为分割的部分，每一个都匹配一个Zookeeper

# server. e.g. "127.0.0.1:3000,127.0.0.1:3001,127.0.0.1:3002".

# You can also append an optional chroot string to the urls to specify the

# root directory for all kafka znodes.

# 您还可以将一个可选的chroot字符串附加到url，以指定所有kafka znode的根目录。

zookeeper.connect=localhost:2181

# Timeout in ms for connecting to zookeeper

# 连接到Zookeeper的超时时间

zookeeper.connection.timeout.ms=6000

# 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.

# see kafka.server.KafkaConfig for additional details and defaults

############################# Server Basics #############################

# The id of the broker. This must be set to a unique integer for each broker.

# 节点的ID，必须与其它节点不同

broker.id=0

# Switch to enable topic deletion or not, default value is false

# 选择启用删除主题功能，默认false

#delete.topic.enable=true

############################# Socket Server Settings #############################

# The address the socket server listens on. It will get the value returned from

# java.net.InetAddress.getCanonicalHostName() if not configured.

# 套接字服务器坚挺的地址。如果没有配置，就使用java.net.InetAddress.getCanonicalHostName()的返回值

#   FORMAT:

#     listeners = listener_name://host_name:port

#   EXAMPLE:

#     listeners = PLAINTEXT://your.host.name:9092

#listeners=PLAINTEXT://:9092

# Hostname and port the broker will advertise to producers and consumers. If not set,

# it uses the value for "listeners" if configured.  Otherwise, it will use the value

# returned from java.net.InetAddress.getCanonicalHostName().

# 节点的主机名会通知给生产者和消费者。如果没有设置，如果配置了"listeners"就使用"listeners"的值。

# 否则就使用java.net.InetAddress.getCanonicalHostName()的返回值

#advertised.listeners=PLAINTEXT://your.host.name:9092

# Maps listener names to security protocols, the default is for them to be the same. See the config documentation for more details

# 将侦听器的名称映射到安全协议，默认情况下它们是相同的。有关详细信息，请参阅配置文档

#listener.security.protocol.map=PLAINTEXT:PLAINTEXT,SSL:SSL,SASL_PLAINTEXT:SASL_PLAINTEXT,SASL_SSL:SASL_SSL

# The number of threads that the server uses for receiving requests from the network and sending responses to the network

# 服务器用来接受请求或者发送响应的线程数

num.network.threads=3

# The number of threads that the server uses for processing requests, which may include disk I/O

# 服务器用来处理请求的线程数，可能包括磁盘IO

num.io.threads=8

# The send buffer (SO_SNDBUF) used by the socket server

# 套接字服务器使用的发送缓冲区大小

socket.send.buffer.bytes=102400

# The receive buffer (SO_RCVBUF) used by the socket server

# 套接字服务器使用的接收缓冲区大小

socket.receive.buffer.bytes=102400

# The maximum size of a request that the socket server will accept (protection against OOM)

# 单个请求最大能接收的数据量

socket.request.max.bytes=104857600

############################# Log Basics #############################

# A comma seperated list of directories under which to store log files

# 一个逗号分隔的目录列表，用来存储日志文件

log.dirs=/tmp/kafka-logs

# The default number of log partitions per topic. More partitions allow greater

# parallelism for consumption, but this will also result in more files across

# the brokers.

# 每个主题的日志分区的默认数量。更多的分区允许更大的并行操作，但是它会导致节点产生更多的文件

num.partitions=1

# The number of threads per data directory to be used for log recovery at startup and flushing at shutdown.

# This value is recommended to be increased for installations with data dirs located in RAID array.

# 每个数据目录中的线程数，用于在启动时日志恢复，并在关闭时刷新。

num.recovery.threads.per.data.dir=1

############################# Internal Topic Settings  #############################

# 内部主题设置

# The replication factor for the group metadata internal topics "__consumer_offsets" and "__transaction_state"

# For anything other than development testing, a value greater than 1 is recommended for to ensure availability such as 3.

# 对于除了开发测试之外的其他任何东西，group元数据内部主题的复制因子“__consumer_offsets”和“__transaction_state”，建议值大于1，以确保可用性(如3)。

offsets.topic.replication.factor=1

transaction.state.log.replication.factor=1

transaction.state.log.min.isr=1

############################# Log Flush Policy #############################

# Messages are immediately written to the filesystem but by default we only fsync() to sync

# the OS cache lazily. The following configurations control the flush of data to disk.

# 消息直接被写入文件系统，但是默认情况下我们仅仅调用fsync()以延迟的同步系统缓存

# There are a few important trade-offs here:

# 这些有一些重要的权衡

#    1. Durability: Unflushed data may be lost if you are not using replication.

#    2. Latency: Very large flush intervals may lead to latency spikes when the flush does occur as there will be a lot of data to flush.

#    3. Throughput: The flush is generally the most expensive operation, and a small flush interval may lead to exceessive seeks.

#    1. 持久性:如果不使用复制，未刷新的数据可能会丢失。

#    2. 延迟:非常大的刷新间隔可能会在刷新时导致延迟，因为将会有大量数据刷新。

#    3. 吞吐量:刷新通常是最昂贵的操作，而一个小的刷新间隔可能会导致过多的搜索。

# The settings below allow one to configure the flush policy to flush data after a period of time or

# every N messages (or both). This can be done globally and overridden on a per-topic basis.

# 下面的设置允许你去配置刷新策略，每隔一段时间刷新或者一次N个消息（或者两个都配置）。这可以在全局范围内完成，并在每个主题的基础上重写。

# The number of messages to accept before forcing a flush of data to disk

# 在强制刷新数据到磁盘之前允许接收消息的数量

#log.flush.interval.messages=10000

# The maximum amount of time a message can sit in a log before we force a flush

# 在强制刷新之前，消息可以在日志中停留的最长时间

#log.flush.interval.ms=1000

############################# Log Retention Policy #############################

# The following configurations control the disposal of log segments. The policy can

# be set to delete segments after a period of time, or after a given size has accumulated.

# 以下的配置控制了日志段的处理。策略可以配置为每隔一段时间删除片段或者到达一定大小之后。

# A segment will be deleted whenever *either* of these criteria are met. Deletion always happens

# from the end of the log.

# 当满足这些条件时，将会删除一个片段。删除总是发生在日志的末尾。

# The minimum age of a log file to be eligible for deletion

# 一个日志的最小存活时间，可以被删除

log.retention.hours=168

# A size-based retention policy for logs. Segments are pruned from the log as long as the remaining

# segments don't drop below log.retention.bytes.

# 一个基于大小的日志保留策略。段将被从日志中删除只要剩下的部分段不低于log.retention.bytes。

#log.retention.bytes=1073741824

# The maximum size of a log segment file. When this size is reached a new log segment will be created.

# 每一个日志段大小的最大值。当到达这个大小时，会生成一个新的片段。

log.segment.bytes=1073741824

# The interval at which log segments are checked to see if they can be deleted according

# to the retention policies

# 检查日志段的时间间隔，看是否可以根据保留策略删除它们

log.retention.check.interval.ms=300000

############################# Zookeeper #############################

# Zookeeper connection string (see zookeeper docs for details).

# Zookeeper连接字符串（具体见Zookeeper文档）

# This is a comma separated host:port pairs, each corresponding to a zk

# 这是一个以逗号为分割的部分，每一个都匹配一个Zookeeper

# server. e.g. "127.0.0.1:3000,127.0.0.1:3001,127.0.0.1:3002".

# You can also append an optional chroot string to the urls to specify the

# root directory for all kafka znodes.

# 您还可以将一个可选的chroot字符串附加到url，以指定所有kafka znode的根目录。

zookeeper.connect=localhost:2181

# Timeout in ms for connecting to zookeeper

# 连接到Zookeeper的超时时间

zookeeper.connection.timeout.ms=6000

############################# Group Coordinator Settings #############################

# The following configuration specifies the time, in milliseconds, that the GroupCoordinator will delay the initial consumer rebalance.

# The rebalance will be further delayed by the value of group.initial.rebalance.delay.ms as new members join the group, up to a maximum of max.poll.interval.ms.

# The default value for this is 3 seconds.

# We override this to 0 here as it makes for a better out-of-the-box experience for development and testing.

# However, in production environments the default value of 3 seconds is more suitable as this will help to avoid unnecessary, and potentially expensive, rebalances during application startup.

group.initial.rebalance.delay.ms=0

#port=9092

#host.name=localhost

#advertised.host.name=<hostname routable by clients>

#advertised.port=<port accessible by clients>

#listeners=PLAINTEXT://:9092

#advertised.listeners=PLAINTEXT://your.host.name:9092

# 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.

# see kafka.server.KafkaConfig for additional details and defaults

############################# Server Basics #############################

# The id of the broker. This must be set to a unique integer for each broker.

# 节点的ID，必须与其它节点不同

broker.id=0

############################# Socket Server Settings #############################

# The address the socket server listens on. It will get the value returned from

# java.net.InetAddress.getCanonicalHostName() if not configured.

#   FORMAT:

#     listeners = listener_name://host_name:port

#   EXAMPLE:

#     listeners = PLAINTEXT://your.host.name:9092

# 套接字服务器监听的地址。如果没有配置，就使用java.net.InetAddress.getCanonicalHostName()的返回值

#listeners=PLAINTEXT://:9092

# Hostname and port the broker will advertise to producers and consumers. If not set,

# it uses the value for "listeners" if configured.  Otherwise, it will use the value

# returned from java.net.InetAddress.getCanonicalHostName().

#advertised.listeners=PLAINTEXT://your.host.name:9092

# Maps listener names to security protocols, the default is for them to be the same. See the config documentation for more details

#listener.security.protocol.map=PLAINTEXT:PLAINTEXT,SSL:SSL,SASL_PLAINTEXT:SASL_PLAINTEXT,SASL_SSL:SASL_SSL

# The number of threads that the server uses for receiving requests from the network and sending responses to the network

# 接受网络请求的线程数

num.network.threads=3

# The number of threads that the server uses for processing requests, which may include disk I/O

# 进行磁盘IO的线程数

num.io.threads=8

# The send buffer (SO_SNDBUF) used by the socket server

# 套接字服务器使用的发送缓冲区大小

socket.send.buffer.bytes=102400

# The receive buffer (SO_RCVBUF) used by the socket server

# 套接字服务器使用的接收缓冲区大小

socket.receive.buffer.bytes=102400

# The maximum size of a request that the socket server will accept (protection against OOM)

# 单个请求最大能接收的数据量

socket.request.max.bytes=104857600

############################# Log Basics #############################

# A comma separated list of directories under which to store log files

# 一个逗号分隔的目录列表，用来存储日志文件

log.dirs=/tmp/kafka-logs

# The default number of log partitions per topic. More partitions allow greater

# parallelism for consumption, but this will also result in more files across

# the brokers.

# 每个主题的日志分区的默认数量。更多的分区允许更大的并行操作，但是它会导致节点产生更多的文件

num.partitions=1

# The number of threads per data directory to be used for log recovery at startup and flushing at shutdown.

# This value is recommended to be increased for installations with data dirs located in RAID array.

# 每个数据目录中的线程数，用于在启动时日志恢复，并在关闭时刷新。

num.recovery.threads.per.data.dir=1

############################# Internal Topic Settings  #############################

# The replication factor for the group metadata internal topics "__consumer_offsets" and "__transaction_state"

# 内部主题“_consumer_offsets”和“_transaction_state”的复制因子

# For anything other than development testing, a value greater than 1 is recommended for to ensure availability such as 3.

# 对于开发测试以外的任何情况，建议使用大于1的值来确保可用性，比如3。

offsets.topic.replication.factor=1

transaction.state.log.replication.factor=1

transaction.state.log.min.isr=1

############################# Log Flush Policy #############################

# Messages are immediately written to the filesystem but by default we only fsync() to sync

# the OS cache lazily. The following configurations control the flush of data to disk.

# 消息直接被写入文件系统，但是默认情况下我们仅仅调用fsync()以延迟的同步系统缓存

# There are a few important trade-offs here:

# 这些有一些重要的权衡

#    1. Durability: Unflushed data may be lost if you are not using replication.

#    2. Latency: Very large flush intervals may lead to latency spikes when the flush does occur as there will be a lot of data to flush.

#    3. Throughput: The flush is generally the most expensive operation, and a small flush interval may lead to excessive seeks.

#    1. 持久性:如果不使用复制，未刷新的数据可能会丢失。

#    2. 延迟:非常大的刷新间隔可能会在刷新时导致延迟，因为将会有大量数据刷新。

#    3. 吞吐量:刷新通常是最昂贵的操作，而一个小的刷新间隔可能会导致过多的搜索。

# The settings below allow one to configure the flush policy to flush data after a period of time or

# every N messages (or both). This can be done globally and overridden on a per-topic basis.

# 下面的设置允许你去配置刷新策略，每隔一段时间刷新或者一次N个消息（或者两个都配置）。这可以在全局范围内完成，并在每个主题的基础上重写。

# The number of messages to accept before forcing a flush of data to disk

# 在强制刷新数据到磁盘之前允许接收消息的数量

#log.flush.interval.messages=10000

# The maximum amount of time a message can sit in a log before we force a flush

# 在强制刷新之前，消息可以在日志中停留的最长时间

#log.flush.interval.ms=1000

############################# Log Retention Policy #############################

# The following configurations control the disposal of log segments. The policy can

# be set to delete segments after a period of time, or after a given size has accumulated.

# 以下的配置控制了日志段的处理。策略可以配置为每隔一段时间删除片段或者到达一定大小之后。

# A segment will be deleted whenever *either* of these criteria are met. Deletion always happens

# from the end of the log.

# 当满足这些条件时，将会删除一个片段。删除总是发生在日志的末尾。

# The minimum age of a log file to be eligible for deletion due to age

# 一个日志的最小存活时间

log.retention.hours=168

# A size-based retention policy for logs. Segments are pruned from the log unless the remaining

# segments drop below log.retention.bytes. Functions independently of log.retention.hours.

# 一个基于大小的日志保留策略。只要剩下的部分不低于log.retention.bytes，段将从日志中删除。

#log.retention.bytes=1073741824

# The maximum size of a log segment file. When this size is reached a new log segment will be created.

# 每一个日志段大小的最大值。当到达这个大小时，会生成一个新的片段。

log.segment.bytes=1073741824

# The interval at which log segments are checked to see if they can be deleted according

# to the retention policies

# 检查日志段的时间间隔，看是否可以根据保留策略删除它们

log.retention.check.interval.ms=300000

############################# Zookeeper #############################

# Zookeeper connection string (see zookeeper docs for details).

# This is a comma separated host:port pairs, each corresponding to a zk

# server. e.g. "127.0.0.1:3000,127.0.0.1:3001,127.0.0.1:3002".

# You can also append an optional chroot string to the urls to specify the

# root directory for all kafka znodes.

# 配置zookeeper地址，多个以逗号分隔，还可以在最后指定kafka存储的namespace：eg："127.0.0.1:3000,127.0.0.1:3001,127.0.0.1:3002/kafka"

zookeeper.connect=localhost:2181

# Timeout in ms for connecting to zookeeper

# 连接到Zookeeper的超时时间

zookeeper.connection.timeout.ms=6000

############################# Group Coordinator Settings #############################

# The following configuration specifies the time, in milliseconds, that the GroupCoordinator will delay the initial consumer rebalance.

# 指定GroupCoordinator延迟初始消费者再平衡的时间(以毫秒为单位)

# The rebalance will be further delayed by the value of group.initial.rebalance.delay.ms as new members join the group, up to a maximum of max.poll.interval.ms.

# The default value for this is 3 seconds.

# 默认值是3秒

# We override this to 0 here as it makes for a better out-of-the-box experience for development and testing.

# However, in production environments the default value of 3 seconds is more suitable as this will help to avoid unnecessary, and potentially expensive, rebalances during application startup.

# 在生产环境中，3秒的默认值更合适

group.initial.rebalance.delay.ms=0

# 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.

# see org.apache.kafka.clients.producer.ProducerConfig for more details

############################# Producer Basics #############################

# list of brokers used for bootstrapping knowledge about the rest of the cluster

# format: host1:port1,host2:port2 ...

bootstrap.servers=localhost:9092

# 指定数据压缩格式：none、gzip、snappy、lz4、zstd

compression.type=none

# name of the partitioner class for partitioning events; default partition spreads data randomly

# 分区策略，默认随机

#partitioner.class=

# the maximum amount of time the client will wait for the response of a request

# 客户端等待请求响应的最大时间，即在向 producer 发送 ack 之前，broker允许等待的最大时间

#request.timeout.ms=

# how long `KafkaProducer.send` and `KafkaProducer.partitionsFor` will block for

# `KafkaProducer.send` and `KafkaProducer.partitionsFor`阻塞的时间

#max.block.ms=

# the producer will wait for up to the given delay to allow other records to be sent so that the sends can be batched together

# 生产者将等待一个延迟，以便和其他的消息组合成一个批次发出，减少发送的请求数

#linger.ms=

# the maximum size of a request in bytes

# 请求的最大字节数

#max.request.size=

# the default batch size in bytes when batching multiple records sent to a partition

# 在批处理消息发送到一个分区的多个记录时的批处理大小，默认16k

#batch.size=

# the total bytes of memory the producer can use to buffer records waiting to be sent to the server

# 生产者可以用来缓存消息的缓冲区大小

#buffer.memory=

# 以下是默认配置文件没有的：更多 http://kafka.apache.org/documentation/#producerconfigs

# 在请求完成之前，生产者要求leader已收到确认消息的数量。

# 0：生产者不会等待服务器的ack响应，不保证服务器收到消息，返回的偏移量总是-1

# 1：leader将消息写入本地日志，但不会管其他follower是否写入。

# all：leader和所有的follower都成功同步消息才会返回ack，保证消息不会丢失。all等价于-1.

acks=