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9.4.41. TimeDelayMsFilter (delayInMS) Filter

The TimeDelayMsFilter delays writing events to the THL and should be used only on Appliers in the remote-to-thl stage. This delays writing the transactions into the THL files, but allows the application of the data to the database to continue without further intervention.

This filter allows delay precision in milliseconds. If you wish to delay to second precision, then the TimeDelay filter would also be appropriate. See Section 9.4.40, “TimeDelay (delay) Filter” for more detail.

Pre-configured filter name delayInMs
Classname com.continuent.tungsten.replicator.filter.TimeDelayMsFilter
Property prefix replicator.filter.delayInMs
Stage compatibility remote-to-thl
tpm Option compatibility --repl-svc-thl-filters
Data compatibility Any event
Parameters
Parameter Type Default Description
delay numeric 60000 Number of milliseconds to delay transaction processing row

The TimeDelayMsFilter delays the application of transactions recorded in the THL. The delay can be used to allow point-in-time recovery of DML operations before the transaction has been applied to the Target, or where data may need to be audited or checked before transactions are committed.

Note

For effective operation, Source and Targets should be synchronized using NTP or a similar protocol.

To enable the TimeDelayMsFilter, update the tungsten.ini configuration file to enable the filter. For example, to enable the delay for 120000 milliseconds:

shell> vi /etc/tungsten/tungsten.ini
[serviceName]
...
svc-applier-filters=delayInMs
property=replicator.filter.delayInMs.delay=120000
...

shel> tpm update

Time delay of transaction events should be performed with care, since the delay will prevent an Target from being up to date compared to the Source. In the event of a node failure, an up to date Target is required to ensure that data is safe.