[
https://issues.apache.org/jira/browse/PHOENIX-2221?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=14903381#comment-14903381
]
Alicia Ying Shu commented on PHOENIX-2221:
------------------------------------------
Currently INDEX_RECOVERY_FAILURE_POLICY_KEY is used in Indexer.java. I can add
it to QueryServices.java. Using it as a config parameter to a new class, I need
to create a new class ReadableIndexFailurePolicy.java for this. However, the
only difference between this new class and PhoenixIndexFailurePolicy.java is
writing READABLE index state. I would like to reuse the codes in
PhoenixIndexFailurePolicy.java (there are private methods in
PhoenixIndexFailurePolicy.java I would like to use). Use
INDEX_RECOVERY_FAILURE_POLICY_KEY to a new class that implements the
IndexFailurePolicy interface would add duplicate codes from
PhoenixIndexFailurePolicy.java. Also we may need to change
PhoenixIndexCodec.java and other parts.
My current implementation checks whether INDEX_FAILURE_BLOCK_WRITE_ATTRIB is
set then set READABLE index state. This approach added least amount of codes (a
few lines of codes on this part). Since we reuse INDEX_DISABLE_TIMESTAMP, it
makes sense to reuse PhoenixIndexFailurePolicy.java. I would suggest keep
INDEX_FAILURE_BLOCK_WRITE_ATTRIB and just make the least amount code changes.
[~jamestaylor] What do you think?
> Option to make data regions not writable when index regions are not available
> -----------------------------------------------------------------------------
>
> Key: PHOENIX-2221
> URL: https://issues.apache.org/jira/browse/PHOENIX-2221
> Project: Phoenix
> Issue Type: Improvement
> Reporter: Devaraj Das
> Assignee: Alicia Ying Shu
> Attachments: PHOENIX-2221.patch
>
>
> In one usecase, it was deemed better to not accept writes when the index
> regions are unavailable for any reason (as opposed to disabling the index and
> the queries doing bigger data-table scans).
> The idea is that the index regions are kept consistent with the data regions,
> and when a query runs against the index regions, one can be reasonably sure
> that the query ran with the most recent data in the data regions. When the
> index regions are unavailable, the writes to the data table are rejected.
> Read queries off of the index regions would have deterministic performance
> (and on the other hand if the index is disabled, then the read queries would
> have to go to the data regions until the indexes are rebuilt, and the queries
> would suffer).
--
This message was sent by Atlassian JIRA
(v6.3.4#6332)
