changefeedccl: periodic pts record updates

[cockroach-teamcity]

Exalate commented:

cockroachdb/cockroach#76605 --- Release note (enterprise change): changefeeds running on tables with a low gcttl will function more reliably due to protected timestamps being maintained for the changefeed targets at the resolved timestamp of the changefeed. The frequency at which the protected timestamp is updated to the resolved timestamp can be configured through the changefeed.protect_timestamp_interval cluster setting. If the changefeed lags too far behind such that storage of old data becomes an issue, cancelling the changefeed will release the protected timestamps and allow garbage collection to resume. If protect_data_from_gc_on_pause is unset, pausing the changefeed will release the existing protected timestamp record.

Jira Issue: DOC-2684

[exalate-issue-sync]

Abbey Russell (amruss) commented:
Before we would only lay a protected timestamp if you paused with gc or during initial scan, now we by default protect changefeed data from being garbage collected

Every 10 minutes it will move the protected timestamp up to the current high water mark

The only way for changefeeds to not protect data is to pause the changefeed without protect_from_gc_on_pause, to cancel the changefeed, or for the changefeed to fail without on_error=pause

We recommend monitoring of storage and of running changefeeds.. now if a changefeed is not advancing and is retrying, it will (without limit) accumulate garbage while it retries to run

• Later work: retry limits