Basic Parameters for Parallel Replicat

The following table lists the basic parallel Replicat parameters and their description.

Parameter Description
MAP_PARALLELISM

Configures number of mappers. This controls the number of threads used to read the trail file. The minimum value is 1, maximum value is 100 and the default value is 2.

APPLY_PARALLELISM

Configures number of appliers. This controls the number of connections in the target database used to apply the changes. The default value is four.

MIN_APPLY_PARALLELISM

MAX_APPLY_PARALLELISM

The Apply parallelism is auto-tuned. You can set a minimum and maximum value to define the ranges in which the Replicat automatically adjusts its parallelism. There are no defaults. Do not use with APPLY_PARALLELISM at same time.

SPLIT_TRANS_REC

Specifies that large transactions should be broken into pieces of specified size and applied in parallel. Dependencies between pieces are still honored. Disabled by default.

COMMIT_SERIALIZATION

Enables commit FULL serialization mode, which forces transactions to be committed in trail order.

Advanced Parameters

 
LOOK_AHEAD_TRANSACTIONS

Controls how far ahead the Scheduler looks when batching transactions. The default value is 10000.

CHUNK_SIZE

Controls how large a transaction must be for parallel Replicat to consider it as large. When parallel Replicat encounters a transaction larger than this size, it will serialize it, resulting in decreased performance. However, increasing this value will also increase the amount of memory consumed by parallel Replicat.

Example Parameter File

Replicat repe
USERID ggadmin, PASSWORD ***
MAP_PARALLELISM 3
MIN_APPLY_PARALLELISM 2
MAX_APPLY_PARALLELISM 10
SPLIT_TRANS_RECS 60000
MAP *.*, TARGET *.*;