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 11.4.45, “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.
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.