Configuration Parameters
This topic describes configuration parameters that are either specific to MapR Event Store For Apache Kafka or supported from Apache Kafka.
Parameter | Description |
---|---|
streams.admin.default.stream |
This parameter, when set during creation of the AdminClient instance,
ensures that the specified stream is using the the AdminClient instance for all
administrative
operations. Syntax:
|
streams.rpc.timeout.ms |
Specifies the length of time in milliseconds to wait for a response from
the MapR Event Store For Apache Kafka server if soft mount is
configured (fs.mapr.hardmount is set to false). Default: 120000 Minimum: 30000
NOTE Applicable as of MapR 6.0.1, is used instead of
fs.mapr.rpc.timeout
For producer and consumer applications, make sure the
|
Parameter | Description |
---|---|
streams.consumer.buffer.memory |
Specifies how much memory to use for caching pre-fetched messages. Messages that are in subscribed topics and partitions are pre-fetched and cached to improve performance. Default 64MB |
streams.consumer.default.stream |
Specifies the path and name of the stream that the consumer subscribes to if, when
subscribing to a topic, the consumer does not specify a stream.
This default value is
also used for the |
streams.rpc.timeout.ms |
Specifies the length of time in milliseconds to wait for a response from the MapR Event Store For Apache Kafka server if a soft mount is configured (fs.mapr.hardmount is set to false). Default: 305000 Minimum: 300000 For producer and consumer applications, make sure the
|
Parameter | Description |
---|---|
auto.commit.interval.ms |
The frequency in milliseconds that the offsets are committed. Default: 1000ms |
auto.offset.reset |
Specifies what MapR Event Store For Apache Kafka should do when there is no initial offset, such as
when a consumer starts reading from a partition. Default: latest
|
enable.auto.commit |
If true, periodically commits the highest offsets of the messages fetched by the consumer in all of the partitions for the topics that the consumer is subscribed to. Default: true |
fetch.min.bytes |
The minimum amount of data the server should return for a fetch request. If
insufficient data is available, the server will wait for this minimum amount of data to
accumulate before answering the request. This minimum applies to the totality of what a consumer has subscribed to. Works in conjunction with the timeout interval that is specified in the poll function. If the minimum number of bytes is not reached by the time that the interval expires, the poll returns with nothing. For example, suppose the value is set to 6 bytes and the timeout on a poll is set to 100ms. If there are 5 bytes available and no further bytes come in before the 100ms expire, the poll returns with nothing. Default: 1 byte |
fetch.max.bytes |
The maximum amount of data the server should return for a fetch request. If the first record
batch in the first non-empty partition of the fetch is larger than this
configuration, the record batch is still returned to ensure that the consumer
can make progress. NOTE This parameter is new as of MapR 6.0.1. |
fetch.max.wait.ms |
The maximum amount of time the MapR Event Store For Apache Kafka server will block before answering the
fetch request if there isn't sufficient data to satisfy the requirement given by
fetch.min.bytes . |
group.id |
A string 2457 up to bytes long that uniquely identifies the group of consumer
processes to which this consumer belongs. By setting the same group ID, multiple
consumer processes indicate that they are all part of the same consumer group. Putting
consumers into groups provides benefits that are described in Consumer Groups. It is possible for a single consumer to be in a group. |
key.deserializer |
The class that implements the Deserializer interface for
deserializing keys. |
max.poll.records |
Places an upper bound on the number of records returned from each call.
NOTE This parameter is new as of MapR 6.0.1. |
max.partition.fetch.bytes |
The number of bytes of message data to attempt to fetch for each partition
in each poll request. These bytes will be read into memory for each partition,
so this parameter helps control the memory that the consumer uses. Default: 64KB
The size of the poll request must be at least as large as the maximum message size that the server allows or else it is possible for producers to send messages that are larger than the consumer can fetch. If the first record batch in the first non-empty partition of the fetch is
larger than this configuration, the record batch is still returned to ensure
that the consumer can make progress.
NOTE This is a behavior change as of
MapR 6.0.1. |
value.deserializer |
The name of the appropriate deserialization class in the org.apache.kafka.common.serialization package or a class that
implements the Deserializer interface for
deserializing values. |
Parameter | Description |
---|---|
streams.buffer.max.time.ms |
Messages are buffered in the producer for at most the specified time. A thread will flush all the messages that have been buffered for more than the time specified. Default: 3 * 1000 msec create default stream |
streams.parallel.flushers.per.partition |
If enabled, producer may have multiple parallel send requests to the server for each topic partition. If this setting is set to true, it is possible for messages to be sent out of order. Default: true create default stream |
streams.partitioner.class |
The class that implements the StreamsPartitioner interface.
This interface lets you write custom algorithms for determining which topic and
partition to use for messages that match specific criteria. Use this configuration
parameter only for producers that are written in Java. create default stream |
streams.producer.default.stream |
Specifies the stream that the
producer will use by default if the producer does not provide the name of a
stream when specifying a topic to write to. Syntax:
create default stream
|
fs.mapr.hardmount |
Specifies whether to use a hard mount or a soft mount for connections to the MapR
Streams server. The default is to use a hard mount and the value is
If a value for this parameter
is set in the |
fs.mapr.rpc.timeout |
Specifies the length of time in seconds to wait for a response from the
MapR Event Store For Apache Kafka server if the configuration
parameter fs.mapr.hardmount is set to false. Default: 300.
Minimum value: 30.NOTE Applicable to MapR 6.0.0 and earlier. As of MapR 6.0.1,
use streams.mapr.timeout.ms .If a soft mount is
used, the time expires while a producer waits for a response from the MapR Event Store For Apache Kafka server, and the producer used the
|
streams.rpc.timeout.ms |
Specifies the length of time in milliseconds to wait for a response from the MapR Event Store For Apache Kafka server if soft mount is configured (fs.mapr.hardmount is set to false). Default: 30000 Minimum: 30000 For producer and consumer applications, make sure the
|
Parameter | Description |
---|---|
buffer.memory |
The total bytes of memory the producer can use to buffer records waiting to be sent to the server. If records are generated faster than they can be delivered to the server the producer will block. Default: 33554432 |
client.id |
Producers can tag records with a client ID that identifies the producer. Consumers can then be aware of which producer sent a message or set of messages. Apache Drill or other analytic tools querying messages can include this ID in the filters for their queries. Default: No client ID. |
key.serializer |
The name of the appropriate serialization class in the org.apache.kafka.common.serialization package or a class
that implements the Serializer interface for
serializing keys. |
metadata.max.age.ms |
The producer generally refreshes the topic metadata from the server when there is a failure. It will also poll for this data regularly. Default: 300 * 1000 msec |
value.serializer |
The class that implements the Serializer interface for
serializing values. |