sre_server.conf

This file controls settings related to the speech server.

It is located by default in /etc/lumenvox/ on Linux and in C:\Program Files\LumenVox\Engine\config\ on Windows. See Configuration Files for more information about other configuration files.

The following parameters can be set. The format to use within the configuration file is PROPERTY_NAME = VALUE

 

SRE_PORTNUM

Description: The port number that the speech server will use to listen for incoming speech requests.

Possible Values: A port number.

Default Value: 5730

ENABLE_CACHE

Description: Whether grammar caching should be turned on or off. Grammar caching allows the server to automatically cache all loaded grammars to disk. This can save a lot of time when loading larger grammars, as they must be compiled before use, and this can take a while for big grammars.

Possible Values: 0 (disabled) or 1 (enabled).

Default Value: 1

CACHE_EXPIRATION

Description: The amount of time, in seconds, the Engine will use a cached grammars on disk. If a cached grammar on disk is older than this value, the Engine will disregard the cached copy. If you are making extensive use of caching to preload very large grammars, you may want to set this very high.

Possible Values: An integer. If it is set to 0, the Engine will never used cached grammars.

Default Value: 1440

CACHE_MAX_NUMBER

Description: The maximum number of grammars to be kept in cache. The higher the number of grammars kept in memory, the more memory gets used in storing them.

Possible Values: An integer. If it is set to 0, the Engine will not cache any grammars.

Default Value: 1000

CACHE_MAX_MEMORY

Description: The maximum amount of memory, in bytes, that can be used to cache grammars

Possible Values: An integer. If it is set to 0, the Engine will not cache any grammars.

Default Value: 268435456 (256 MB)

NUM_DECODE_THREADS

Description: The maximum number of processing threads for decoding audio. This parameter should NOT be modified at all, unless instructed by LumenVox support.

Possible Values: An integer. If it is set to 0, the Engine will not perform any decodes.

Default Value: 4

LOAD_XXX_RES_MODEL

Description: Determines which of the three resolution levels (LOW, MED, HIGH) of acoustic model are loaded. Combinations (LOW and HIGH) can be enabled, but the lower resolution will be defaulted to. These are currently experimental and we recommend that users leave only the LOAD_LOW_RES_MODEL enabled (the default).

Possible Values: 0 (disabled) or 1 (enabled)

Default Value: LOW enabled
LOAD_LOW_RES_MODEL = 1
LOAD_MED_RES_MODEL = 0
LOAD_HIGH_RES_MODEL = 0

FRAME_TRACK_MODE

Description: Controls speed and memory use as they relate to quality of confidence scores.

Possible Values: If set to 0, confidence scores will be poor but memory use will be lowered and decode speed will be increased. If set to 1, confidence scores will be good, memory use will be medium, but decode speeds will be slow. If set to 2, confidence scores will be good, memory use will be high, and decode speeds will be medium. In most cases, you should set this to either 1 or 2 depending on how you value speed versus memory use.

Default Value: 2

CRITICAL_MEMORY_THRESHOLD

Description: When the system running the speech server falls below this many available MB of memory, the speech server will enter a critical resource mode. This causes it to serialize all decode tasks, attempt to free up pooled memory and grammars, and disables frame tracking (resulting in worse confidence scores).

Possible Values: An integer representing the minimum amount of free system memory (in MB) you wish to have before the system enters critical resource mode.

Default Value: 100

LOW_MEMORY_THRESHOLD

Description: When the system running the speech server falls below this many available MB of memory, the speech server will enter low resource mode. This causes it to reduce the number of decode tasks it will handle in parallel.

Possible Values: An integer representing the minimum amount of free system memory (in MB) you wish to have before the system enters low resource mode.

Default Value: 250

LIMITED_MEMORY_THRESHOLD

Description: When the system running the speech server falls below this many available MB of memory, the speech server will enter limited resource mode. This causes it to reduce the number of decode tasks it will handle in parallel and limit frame track mode to 0 or 1.

Possible Values: An integer representing the minimum amount of free system memory (in MB) you wish to have before the system enters limited resource mode.

Default Value: 750

FST_DETERMINIZE_SUBSET_LIMIT

Description: The maximum size a subset list can grow during FST determinization before it gives up. This value is a safeguard against determinization operations that can recurse infinitely or take an unreasonable amount of time and resources to complete.

Possible Values: A positive integer.

Default Value: 50000

LOGGING_VERBOSITY

Description: Controls the verbosity of event logging. This can be used to increase or decrease the amount of information logged by the application. Note that increasing the logging verbosity causes increase in CPU usage, and should therefore be avoided wherever possible in a production environment where optimal performance is critical.

Possible Values: 1 - 3
1 = Minimal logging. Logs only errors and critical issues.
2 = Medium logging. Logs all non-debug inofrmation, includes types covered in Minimal logging as well.
3 = Maximum logging. Logs all types of events. This will include any and all informational and debugging activity.

Default Value: 1