Node-specific configurations

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Setting up node-specific configurations

Node-specific configurations can be set in the risingwave.toml configuration file. Here’s the steps on how to set them up:

1. Create or locate your risingwave.toml file. This file will contain all your node-specific configurations. If it doesn’t exist, create a new one.
2. Edit the risingwave.toml file. Open the file in a text editor. Each configuration item should be specified in the format config_name = value. For example:

[storage.data_file_cache]
dir = "/risingwave/foyer/meta"
capacity_mb = 20480

3. Save your changes. After editing, save the risingwave.toml file.
4. Provide the configuration file to the node. You can do this via the --config-path command-line argument when starting the node. For example:

risingwave --config-path=/path/to/risingwave.toml

Alternatively, you can set the RW_CONFIG_PATH environment variable to the path of your risingwave.toml file. For example, in a Kubernetes environment, you can copy the configuration file into the Docker container, or mount a path containing the configuration file into the pod. Then, specify the path to the configuration file using the RW_CONFIG_PATH environment variable or the --config-path command-line argument. 5. Restart the node. For the changes to take effect, you must restart the node.

Any items present in risingwave.toml will override the default values in the source code. If no configuration file is specified, the default values in /risingwave/src/common/src/config.rs will be used.

For more details about the parameters in the configuration file, see RisingWave configuration files directory. There you’ll find information like the definitions and default values of these parameters.

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Node-specific configurations

Configurations for different components lie under different TOML sections. Here’s an example:

[system]
barrier_interval_ms = 1000
checkpoint_frequency = 1
state_store = "hummock+minio://hummockadmin:hummockadmin@127.0.0.1:9301/hummock001"
data_directory = "hummock_001"
backup_storage_url = "minio://hummockadmin:hummockadmin@127.0.0.1:9301/hummock001"
backup_storage_directory = "hummock_001/backup"

[storage.cache_refill]
data_refill_levels = []
timeout_ms = 6000
concurrency = 10
unit = 64
threshold = 0.5
recent_filter_layers = 6
recent_filter_rotate_interval_ms = 10000

When setting up configurations, please be extra careful with those items prefixed by unsafe_. Typically these configurations can cause system or data damage if wrongly configured. You may want to contact our technical support before changing the unsafe_ prefixed configurations.

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System configurations

System configurations are used to initialize the system parameters at the first startup. Once the system has started, the system parameters are managed by Meta service and can be altered using the ALTER SYSTEM SET command.

Example for the system configuration section:

[system]
barrier_interval_ms = 1000
checkpoint_frequency = 1
state_store = "hummock+minio://hummockadmin:hummockadmin@127.0.0.1:9301/hummock001"
data_directory = "hummock_001"
backup_storage_url = "minio://hummockadmin:hummockadmin@127.0.0.1:9301/hummock001"
backup_storage_directory = "hummock_001/backup"

For more information on system parameters, please refer to View and configure system parameters.

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Streaming configurations

Streaming configurations can be set in [streaming] section in the configuration file. For example:

[streaming]
unsafe_enable_strict_consistency = true

RisingWave now supports the following configurations:

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Storage configurations

Storage configurations can be set in [storage] and [storage.xxx] sections.

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File cache and block cache

In RisingWave, several node-specific configurations are provided to control the refilling process of file cache and block cache.

For now, the file cache and cache refilling features are still in technical preview. The configuration items might change in future versions.

The configuration of the file cache and the block cache refilling is separated into 3 parts:

1. Data file cache config: [storage.data_file_cache]
2. Meta file cache config: [storage.meta_file_cache]
3. Cache refill config: [storage.cache_refill]

Below is an example of the data file cache configuration for your reference. Please be aware that the data file cache configuration and the meta file cache configuration share the same options.

The cache refill configuration is responsible for managing the behavior of LSM-tree data block cache refilling after compaction. The data blocks are refilling at the unit level, where a unit refers to a range of continuous data blocks that are batched and refilled together in one request.

RisingWave uses a recent filter to decide whether to fill a block or unit. The recent filter is a multi-layer hash set. The first layer records the accessed block IDs within a time window. When each time window passes, the recent filter will add a new layer to record and evict the last layer. Blocks whose IDs appear in the recent filter will be treated as “recently used”. When the “recently used” block ratio exceeds a threshold, the unit will be refilled.

Below is an example of the cache refill configuration for your reference.

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Other storage configurations

Except for the above, RisingWave also provides some other storage configurations to help control the overall buffer and cache limits. Please see Dedicated compute node for more.