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Client protocol properties

The following sections provide a reference for all properties related to the client protocol.

Spooling protocol properties​

The following properties are related to the Client protocol.

protocol.spooling.enabled​

Enable the support for the client Client protocol. The protocol is used if client drivers and applications request usage, otherwise the direct protocol is used automatically.

protocol.spooling.shared-secret-key​

A required 256 bit, base64-encoded secret key used to secure spooled metadata exchanged with the client. Create a suitable value with the following command:

openssl rand -base64 32

protocol.spooling.retrieval-mode​

Determines how the client retrieves the segment. Following are possible values:

  • STORAGE - client accesses the storage directly with the pre-signed URI. Uses one client HTTP request per data segment.
  • COORDINATOR_STORAGE_REDIRECT - client first accesses the coordinator, which redirects the client to the storage with the pre-signed URI. Uses two client HTTP requests per data segment.
  • COORDINATOR_PROXY - client accesses the coordinator and gets data segment through it. Uses one client HTTP request per data segment, but requires a coordinator HTTP request to the storage.
  • WORKER_PROXY - client accesses the coordinator, which redirects to an available worker node. It fetches the data from the storage and provides it to the client. Uses two client HTTP requests, and requires a worker request to the storage.

protocol.spooling.encoding.json.enabled​

Activate support for using uncompressed JSON encoding for spooled segments.

protocol.spooling.encoding.json+zstd.enabled​

Activate support for using JSON encoding with Zstandard compression for spooled segments.

protocol.spooling.encoding.json+lz4.enabled​

Activate support for using JSON encoding with LZ4 compression for spooled segments.

protocol.spooling.encoding.compression.threshold​

Threshold for enabling compression with larger segments.

protocol.spooling.initial-segment-size​

  • Type: Properties reference
  • Default value: 8MB
  • Minimum value: 1kB
  • Maximum value: 128MB
  • Session property: spooling_initial_segment_size

Initial size of the spooled segments.

protocol.spooling.max-segment-size​

  • Type: Properties reference
  • Default value: 16MB
  • Minimum value: 1kB
  • Maximum value: 128MB
  • Session property: spooling_max_segment_size

Maximum size for each spooled segment.

protocol.spooling.inlining.enabled​

Allow spooled protocol to inline initial rows to decrease time to return the first row.

protocol.spooling.inlining.max-rows​

  • Type: Properties reference
  • Default value: 1000
  • Minimum value: 1
  • Maximum value: 1000000
  • Session property: spooling_inlining_max_rows

Maximum number of rows to inline per worker.

protocol.spooling.inlining.max-size​

  • Type: Properties reference
  • Default value: 128kB
  • Minimum value: 1kB
  • Maximum value: 1MB
  • Session property: spooling_inlining_max_size

Maximum size of rows to inline per worker.

Spooling file system properties​

The following properties are used to configure the object storage used with the Client protocol.

fs.azure.enabled​

Activate Azure Storage file system support for spooling segments.

fs.s3.enabled​

Activate S3 file system support for spooling segments.

fs.gcs.enabled​

Activate Google Cloud Storage file system support for spooling segments.

fs.location​

The object storage location to use for spooling segments. Must be accessible by the coordinator and all workers. With the protocol.spooling.retrieval-mode retrieval modes STORAGE and COORDINATOR_STORAGE_REDIRECT the location must also be accessible by all clients. Valid location values vary by object storage type, and follow these patterns:

Examples:

  • S3: s3://my-spooling-bucket/my-segments/
  • Azure Storage: abfss://my-spooling-container@account.dfs.core.windows.net/my-segments/
  • Google Cloud Storage: gs://my-spooling-bucket/my-segments/
note

For Azure Storage, use the ABFS format with hierarchical namespace enabled. The legacy WASB format (wasbs:// or wasb://) is also supported but deprecated.

warning

The specified object storage location must not be used for spooling for another Trino cluster or any object storage catalog. When using the same object storage for multiple services, you must use separate locations for each one. For example:

  • s3://my-spooling-bucket/my-segments/cluster1-spooling/
  • s3://my-spooling-bucket/my-segments/cluster2-spooling/
  • s3://my-spooling-bucket/my-segments/iceberg-catalog/

fs.segment.ttl​

Maximum available time for the client to retrieve spooled segment before it expires and is pruned.

fs.segment.direct.ttl​

Maximum available time for the client to retrieve spooled segment using the pre-signed URI.

fs.segment.encryption​

Encrypt segments with ephemeral keys using Server-Side Encryption with Customer key (SSE-C).

fs.segment.explicit-ack​

Activate pruning of segments on client acknowledgment of a successful read of each segment.

fs.segment.pruning.enabled​

Activate periodic pruning of expired segments.

fs.segment.pruning.interval​

Interval to prune expired segments.

fs.segment.pruning.batch-size​

Number of expired segments to prune as a single batch operation.

Shared protocol properties​

The following properties are related to the Client protocol and the Client protocol, formerly named the V1 protocol.

protocol.v1.prepared-statement-compression.length-threshold​

Prepared statements that are submitted to Trino for processing, and are longer than the value of this property, are compressed for transport via the HTTP header to improve handling, and to avoid failures due to hitting HTTP header size limits.

protocol.v1.prepared-statement-compression.min-gain​

Prepared statement compression is not applied if the size gain is less than the configured value. Smaller statements do not benefit from compression, and are left uncompressed.