The TimeDelayFilter 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.
From version 6.1.4 the delayInMs Filter was also added which allows delay prescion in milliseconds. See Section 10.4.45, “TimeDelayMsFilter (delayInMS) Filter” for more detail.
| Pre-configured filter name |
delay
| ||
| Classname |
com.continuent.tungsten.replicator.filter.TimeDelayFilter
| ||
| Property prefix |
replicator.filter.delay
| ||
| Stage compatibility | remote-to-thl | ||
| tpm Option compatibility |
--repl-svc-thl-filters
| ||
| Data compatibility | Any event | ||
| Parameters | |||
| Parameter | Type | Default | Description |
delay
| numeric | 300 | Number of seconds to delay transaction processing row |
The TimeDelayFilter 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.
For effective operation, Source and Targets should be synchronized using NTP or a similar protocol.
To enable the TimeDelayFilter, update the
tungsten.ini configuration file to enable the filter.
For example, to enable the delay for 600 seconds:
shell>vi /etc/tungsten/tungsten.ini[serviceName] ... svc-applier-filters=delay property=replicator.filter.delay.delay=600 ... shel>tpm update
Time delay of transaction events should be performed with care, since the delay will prevent a 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.