MAX_HEAP_SIZE

The maximum heap memory size that IoTDB can use at startup.

String

On Linux or MacOS, the default is one quarter of the memory. On Windows, the default value for 32-bit systems is 512M, and the default for 64-bit systems is 2G.

HEAP_NEWSIZE

The minimum heap memory size that IoTDB can use at startup.

String

On Linux or MacOS, the default is min{cores * 100M, one quarter of MAX_HEAP_SIZE}. On Windows, the default value for 32-bit systems is 512M, and the default for 64-bit systems is 2G.

JMX_LOCAL

JMX monitoring mode, configured as yes to allow only local monitoring, no to allow remote monitoring

Enum String: “true”, “false”

true

JMX_PORT

JMX listening port. Please confirm that the port is not a system reserved port and is not occupied

Short Int: [0,65535]

31999

JMX_IP

JMX listening address. Only take effect if JMX_LOCAL=false. 0.0.0.0 is never allowed

String

127.0.0.1

compressor

Data compression method

Enum String : “UNCOMPRESSED”, “SNAPPY”

UNCOMPRESSED

group_size_in_byte

The data size written to the disk per time

Int32

134217728

page_size_in_byte

The maximum size of a single page written in memory when each column in memory is written (in bytes)

Int32

65536

max_number_of_points_in_page

The maximum number of data points (timestamps - valued groups) contained in a page

Int32

1048576

max_degree_of_index_node

The maximum degree of the metadata index tree (that is, the max number of each node’s children)

Int32

1024

max_string_length

The maximum length of a single string (number of character)

Int32

128

time_series_data_type

Timestamp data type

Enum String: “INT32”, “INT64”

Int64

time_encoder

Encoding type of time column

Enum String: “TS_2DIFF”,“PLAIN”,“RLE”

TS_2DIFF

value_encoder

Encoding type of value column

Enum String: “TS_2DIFF”,“PLAIN”,“RLE”

PLAIN

float_precision

The precision of the floating point number.(The number of digits after the decimal point)

Int32

The default is 2 digits. Note: The 32-bit floating point number has a decimal precision of 7 bits, and the 64-bit floating point number has a decimal precision of 15 bits. If the setting is out of the range, it will have no practical significance.

bloomFilterErrorRate

The false positive rate of bloom filter in each TsFile. Bloom filter checks whether a given time series is in the tsfile before loading metadata. This can improve the performance of loading metadata and skip the tsfile that doesn’t contain specified time series. If you want to learn more about its mechanism, you can refer to: wiki page of bloom filter。

float, (0, 1)

0.05

rpc_address

The jdbc service listens on the address.

String

“0.0.0.0”

rpc_port

The jdbc service listens on the port. Please confirm that the port is not a system reserved port and is not occupied.

Short Int : [0,65535]

6667

time_zone

The time zone in which the server is located, the default is Beijing time (+8)

Time Zone String

+08:00

base_dir

The IoTDB system folder. It is recommended to use an absolute path.

String

data

data_dirs

The directories of data files. Multiple directories are separated by comma. The starting directory of the relative path is related to the operating system. It is recommended to use an absolute path. If the path does not exist, the system will automatically create it.

String[]

data/data

wal_dir

Write Ahead Log storage path. It is recommended to use an absolute path.

String

data/wal

enable_wal

Whether to enable the pre-write log. The default value is true(enabled), and false means closed.

Bool

true

enable_parameter_adapter

enable dynamically adjusting system to avoid OOM

Bool

true

memtable_size_threshold

max memtable size

Long

1073741824

avg_series_point_number_threshold

max average number of point of each series in memtable

Int32

10000

tsfile_size_threshold

max tsfile size

Long

536870912

enable_partition

Whether enable time partition for data, if disabled, all data belongs to partition 0

Bool

false

partition_interval

Time range for dividing storage group, time series data will be divided into groups by this time range

Int64

604800

concurrent_writing_time_partition

This config decides how many time partitions in a storage group can be inserted concurrently

For example, your partitionInterval is 86400 and you want to insert data in 5 different days,

Int32

1

multi_dir_strategy

IoTDB’s strategy for selecting directories for TsFile in tsfile_dir. You can use a simple class name or a full name of the class. The system provides the following three strategies:

1. SequenceStrategy: IoTDB selects the directory from tsfile_dir in order, traverses all the directories in tsfile_dir in turn, and keeps counting;

2. MaxDiskUsableSpaceFirstStrategy: IoTDB first selects the directory with the largest free disk space in tsfile_dir;

3. MinFolderOccupiedSpaceFirstStrategy: IoTDB prefers the directory with the least space used in tsfile_dir;

4. UserDfineStrategyPackage (user-defined policy)

You can complete a user-defined policy in the following ways:

1. Inherit the cn.edu.tsinghua.iotdb.conf.directories.strategy.DirectoryStrategy class and implement its own Strategy method;

2. Fill in the configuration class with the full class name of the implemented class (package name plus class name, UserDfineStrategyPackage);

3. Add the jar file to the project.

String

MaxDiskUsableSpaceFirstStrategy

tsfile_size_threshold

When a TsFile size on the disk exceeds this threshold, the TsFile is closed and open a new TsFile to accept data writes. The unit is byte and the default value is 2G.

Int64

536870912

tag_attribute_total_size

The maximum persistence size of tags and attributes of each time series.

Int32

700

enable_partial_insert

Whether continue to write other measurements if some measurements are failed in one insertion.

Bool

true

flush_wal_threshold

After the WAL reaches this value, it is flushed to disk, and it is possible to lose at most flush_wal_threshold operations.

Int32

10000

force_wal_period_in_ms

The period during which the log is periodically forced to flush to disk(in milliseconds)

Int32

10

fetch_size

The amount of data read each time in batch (the number of data strips, that is, the number of different timestamps.)

Int32

10000

merge_concurrent_threads

THe max threads which can be used when unsequence data is merged. The larger it is, the more IO and CPU cost. The smaller the value, the more the disk is occupied when the unsequence data is too large, the reading will be slower.

Int32

0

enable_stat_monitor

Whether to enable background statistics

Boolean

false

back_loop_period_in_second

The frequency at which the system statistic module triggers(in seconds).

Int32

5

concurrent_flush_thread

The thread number used to perform the operation when IoTDB writes data in memory to disk. If the value is less than or equal to 0, then the number of CPU cores installed on the machine is used. The default is 0.

Int32

0

stat_monitor_detect_freq_in_second

The time interval which the system check whether the current record statistic time range exceeds stat_monitor_retain_interval every time (in seconds) and perform regular cleaning

Int32

600

stat_monitor_retain_interval_in_second

The retention time of system statistics data(in seconds). Statistics data over the retention time range will be cleaned regularly.

Int32

600

tsfile_storage_fs

The storage file system of Tsfile and related data files. Currently LOCAL file system and HDFS are supported.

String

LOCAL

core_site_path

Absolute file path of core-site.xml if Tsfile and related data files are stored in HDFS.

String

/etc/hadoop/conf/core-site.xml

hdfs_site_path

Absolute file path of hdfs-site.xml if Tsfile and related data files are stored in HDFS.

String

/etc/hadoop/conf/hdfs-site.xml

hdfs_nameservices

Nameservices of HDFS HA if using Hadoop HA

String

hdfsnamespace

hdfs_ha_namenodes

Namenodes under DFS nameservices of HDFS HA if using Hadoop HA

String

nn1,nn2

dfs_ha_automatic_failover_enabled

Whether using automatic failover if using Hadoop HA

Boolean

true

dfs_client_failover_proxy_provider

Proxy provider if using Hadoop HA and enabling automatic failover

String

org.apache.hadoop.hdfs.server.namenode.ha.ConfiguredFailoverProxyProvider

hdfs_use_kerberos

Whether use kerberos to authenticate hdfs

String

false

kerberos_keytab_file_path

Full path of kerberos keytab file

String

/path

kerberos_principal

Kerberos pricipal

String

your principal

authorizer_provider_class

the class name of the authorization service

String

org.apache.iotdb.db.auth.authorizer.LocalFileAuthorizer

After restart system

openID_url

the openID server if OpenIdAuthorizer is enabled

String (a http url)

no

enable_auto_create_schema

whether auto create the time series when a non-existed time series data comes

true or false

true

default_storage_group_level

Storage group level when creating schema automatically is enabled. For example, if we receives a data point from root.sg0.d1.s2, we will set root.sg0 as the storage group if storage group level is 1. (root is level 0)

integer

1

boolean_string_infer_type

To which type the values “true” and “false” should be reslved

BOOLEAN or TEXT

BOOLEAN

integer_string_infer_type

To which type an integer string like “67” in a query should be resolved

INT32, INT64, DOUBLE, FLOAT or TEXT

DOUBLE

nan_string_infer_type

To which type the value NaN in a query should be resolved

DOUBLE, FLOAT or TEXT

FLOAT

floating_string_infer_type

To which type a floating number string like “6.7” in a query should be resolved

DOUBLE, FLOAT or TEXT

FLOAT