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https://issues.apache.org/jira/browse/IGNITE-17261?page=com.atlassian.jira.plugin.system.issuetabpanels:all-tabpanel
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Alexander Lapin updated IGNITE-17261:
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Attachment: Screenshot from 2022-07-06 17-00-26.png
> Implement write intent resolution logic for RO reads
> ----------------------------------------------------
>
> Key: IGNITE-17261
> URL: https://issues.apache.org/jira/browse/IGNITE-17261
> Project: Ignite
> Issue Type: Improvement
> Reporter: Alexander Lapin
> Priority: Major
> Labels: ignite-3, transaction3_ro
> Attachments: Screenshot from 2022-07-06 17-00-26.png
>
>
> Because of lock-free nature, RO reads might interact with writeIntents,
> meaning that such intents should be either evaluated as committed, aborted or
> pending. In order to perform writeIntent resolution it's required to check
> [txnState|https://issues.apache.org/jira/browse/IGNITE-16882] along with
> [adjusting HLC timestamp|https://issues.apache.org/jira/browse/IGNITE-17222]
> on txnStates group. If transaction occurred to be
> * pending (there is no explicit txnState for given txnId specified in
> writeIntent) or txnState is ABORTED - writeIntent ignored.
> * COMMITTED - writeInent returned as RO read response.
> Please pay attention that, as was mentioned above, besides writeIntent
> resolution itself, it's required to adjust HLC timestamp on txnState
> partition in order to guarantee RO reads and tx commit linearizability,
> meaning that it's illegal to commit transaction with commitTimestamp less or
> equal to RO timestamp that already resolved corresponding writeInent as
> pending. It's not only required to perform timestamp adjustment but it's also
> important to do it atomically to txnState switch.
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