Custom Parameters
a9s Search Custom Parameters
As mentioned in Using an a9s Data Service - Custom Parameters as an end user, an Application Developer has the opportunity to customize their Service Instance by using custom parameters.
Tuning
As usage of an a9s Search instance grows you may need to tune the OpenSearch to meet demand.
The following custom parameters are available for tuning the used memory:
| Name | Description | Min | Max | Default |
|---|---|---|---|---|
java_heapspace | The amount of memory (in MB) allocated as heap by the JVM for OpenSearch | 256 | %50 of VM memory (check your plan details) | not set, 46% of available memory will be used |
java_maxmetaspace | The amount of memory (in MB) used by the JVM to store metadata for OpenSearch | 256 | 1024 | 512 |
Additionally there is a custom parameter available to set the used Garbage Collector:
| Name | Description | Default | Available Options |
|---|---|---|---|
java_garbage_collector | The JVM Garbage Collector to be used for OpenSearch. | UseG1GC | UseSerialGC, UseParallelGC, UseParallelOldGC, UseG1GC |
TLS
tls-protocols
You can specify the allowed TLS protocols via the custom parameter tls-protocols.
The custom parameter tls-protocols correlates with OpenSearch's configuration
parameters plugins.security.ssl.http.enabled_protocols and plugins.security.ssl.transport.enabled_protocols, see
Limiting TLS Protocols Used by the Server.
An array with protocol versions is expected. Only Java format is supported.
The allowed protocol version values are TLSv1.3 and TLSv1.2.
tls-ciphers
You can limit the TLS ciphers via the custom parameter tls-ciphers.
The custom parameter tls-ciphers correlates with OpenSearch's configuration
parameters plugins.security.ssl.http.enabled_ciphers and plugins.security.ssl.transport.enabled_ciphers,
see Configuring Cipher Suites.
An array with cipher names is expected. Only Java format is supported.
WARNING: There is no validation enabled for the user provided value and therefore existing instances can break when applying this parameter.
Enable Custom Plugins
You can use the cf update-service command with the -c flag to enable plugins on demand such as the analysis-phonetic plugin which convert tokens to their phonetic representation using Soundex, Metaphone, and a variety of other algorithms.
To enable the analysis phonetic plugin you would use the following command:
cf update-service my-search-service \
-c '{"plugins": ["analysis-phonetic"]}'
The currently available plugins are:
repository-s3(enabled by default, cannot be disabled)repository-azure(enabled by default, cannot be disabled)analysis-phonetic