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Kinetica provides a SQL interface for managing system properties, which control everything from GPUs, hostnames, storage, graph server, and more. The ability to manage system properties is available through SQL, using the following commands:

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ALTER SYSTEM SET PROPERTIES

Only a small subset of the system properties can be altered at runtime. See the /alter/system/properties endpoint documentation for the full list. Only users with the system_admin permission can issue this command.
ALTER SYSTEM SET PROPERTIES Syntax
ALTER SYSTEM SET PROPERTIES ('<property key>' = '<property value>'[,...])
[WITH OPTIONS ('persist' = < 'true' | 'false' >)]
Use the WITH OPTIONS clause to specify whether the setting should be saved to the system configuration to be used after future database restarts. Set the persist option to false to only change the property temporarily, until the database is restarted. By default, the change will be persisted.

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Alterable Properties

Not all system properties can be modified while the system is running. The following is a list of those that can be modified.

enable_audit

Enable or disable auditing.

audit_headers

Enable or disable auditing of request headers.

audit_body

Enable or disable auditing of request bodies.

audit_data

Enable or disable auditing of request data.

audit_response

Enable or disable auditing of response information.

tps_per_tom

Size of the worker rank data processing thread pool. This includes operations such as inserts, updates, & deletes on table data. Multi-head inserts are not affected by this limit. The minimum allowed value is 2. The maximum allowed value is 8192.

tcs_per_tom

Size of the worker rank data calculation thread pool. This is primarily used for computation-based operations such as aggregates and record retrieval. The minimum allowed value is 2. The maximum allowed value is 8192.

subtask_concurrency_limit

Maximum number of simultaneous threads allocated to a given request, per rank. Note that thread allocation may also be limited by resource group limits and/or system load.

concurrent_kernel_execution

Enable or disable concurrent kernel execution.

max_concurrent_kernels

Maximum number of kernels that can be running at the same time on a given GPU. Set to 0 for no limit. Only takes effect if concurrent_kernel_execution is true. The maximum allowed value is 256.

max_get_records_size

The maximum number of records the database will serve for a given data retrieval call. The maximum allowed value is 1000000.

request_timeout

Number of minutes after which filtering (e.g., /filter) and aggregating (e.g., /aggregate/groupby) queries will time out. The maximum allowed value is 1440.

enable_overlapped_equi_join

Enable or disable the overlapped-equi-join filter.

chunk_size

Number of records per chunk, applied to all new tables. To disable chunking, use 0.

chunk_column_max_memory

Maximum data size, in bytes, for each column in a chunk, applied to all new tables. Use 0 for no maximum.

chunk_max_memory

Maximum data size for all columns in a chunk, applied to all new tables. Use 0 for no maximum; use -1 to use the default, based on RAM tier limits or host memory per rank.

execution_mode

Scheme to use for kernel executions. Possible values:
ModeDescription
hostExecute kernels only on the host (CPU)
deviceExecute kernels only on the device (GPU)
defaultExecution engine decides whether to execute kernels on the host or the device
<rows>Execute kernels on the host if the chunked column contains the given number of rows or fewer; otherwise, execute on the device

shadow_agg_size

Maximum number of bytes in the shadow aggregate chunk cache. The maximum allowed value is 2147483647.

shadow_filter_size

Maximum number of bytes in the shadow filter chunk cache. The maximum allowed value is 2147483647.

telm_persist_query_metrics

Enable or disable persisting of query metrics in a table. If disabled, metrics will still be available for point-in-time export.

postgres_proxy_idle_connection_timeout

PostgreSQL Wire Protocol service idle connection timeout, in seconds

postgres_proxy_keep_alive

Enable or disable PostgreSQL Wire Protocol service’s keep alive.

ai_enable_rag

Enable or disable SQL-GPT RAG.

ai_api_provider

AI API provider type

ai_api_url

AI API URL

ai_api_key

AI API key

ai_api_embeddings_model

AI API embeddings model name

ai_api_connection_timeout

AI API connection timeout, in seconds

external_files_directory

Root directory path, on the head node of the cluster, from where external table data files are accessed.

egress_single_file_max_size

Maximum file size, in MB, to allow saving to a single file. May be overridden by target limitations. The maximum allowed value is 200000.

egress_parquet_compression

Parquet file compression type. The supported values are:
  • uncompressed
  • snappy
  • gzip

kafka_batch_size

Maximum number of Kafka records to be ingested in a single batch. The maximum allowed value is 10000000.

kafka_wait_time

Maximum time, in seconds, to buffer records received from Kafka before ingestion. The maximum allowed value is 120.

kafka_poll_timeout

Maximum time, in milliseconds, for each poll to get records from Kafka. The maximum allowed value is 1000.

system_metadata_retention_period

For persistent metadata tables, the time, in seconds, to retain rows prior to deletion. Note that records are deleted periodically, so this retention period is the minimum lifetime of a given metadata record.

kifs_directory_data_limit

Default maximum capacity to apply to a newly-created KiFS directory, in bytes. Use -1 for no limit.

enable_one_step_compound_equi_join

Enable or disable the one-step compound equi-join algorithm.

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Examples

To increase the request timeout and the maximum /get/records size permanently (in the startup configuration):
ALTER SYSTEM SET PROPERTIES Example
ALTER SYSTEM SET PROPERTIES (
    'request_timeout' = '25',
    'max_get_records_size' = '25000'
)
To set the default embeddings model until the database is restarted:
ALTER SYSTEM SET Default Embedding Model Temporarily Example
ALTER SYSTEM SET PROPERTIES ('ai_enable_rag' = 'true')
WITH OPTIONS ('persist' = 'false')

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SHOW SYSTEM PROPERTIES

System properties can be shown by any user.
SHOW SYSTEM PROPERTIES Syntax
SHOW SYSTEM PROPERTIES
[WITH OPTIONS ('properties' = '<config parameter name>[,...]')]

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Examples

To show all system properties:
SHOW SYSTEM PROPERTIES Example
SHOW SYSTEM PROPERTIES
To show the internal & external cluster node URLs:
SHOW SYSTEM PROPERTIES Individually Example
SHOW SYSTEM PROPERTIES
WITH OPTIONS ('properties' = 'conf.worker_http_server_urls,conf.worker_http_server_urls_private')
To show all RAM tier properties:
SHOW RAM Tier Properties Example
SHOW SYSTEM PROPERTIES
WITH OPTIONS
(
    'properties' =
    '
        conf.tier.ram.default.high_watermark,
        conf.tier.ram.default.limit,
        conf.tier.ram.default.low_watermark,
        conf.tier.ram.rank0.high_watermark,
        conf.tier.ram.rank0.limit,
        conf.tier.ram.rank0.low_watermark,
        conf.tier.ram.rank1.high_watermark,
        conf.tier.ram.rank1.limit,
        conf.tier.ram.rank1.low_watermark,
        conf.tier.ram.rank2.high_watermark,
        conf.tier.ram.rank2.limit,
        conf.tier.ram.rank2.low_watermark
    '
)