[
https://issues.apache.org/jira/browse/HBASE-13262?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=14378559#comment-14378559
]
Jonathan Lawlor commented on HBASE-13262:
-----------------------------------------
[~elserj] Nice patch, some review below
Nice tests, I especially like the new TestClientScanner
bq. // TODO Use the server's response about more results
Not sure what this line means, do we need to check the more results flag here?
I like the idea of using moreResults flag but I believe we need to actually
introduce a new flag into the ScanResponse. Unfortunately, the name moreResults
is a little misleading as it seems perfect for what we are trying to achieve.
Looking into RSRpcServices to see when this moreResults flag is set to false,
it looks like this happens only when scanner.isFilterDone() is true. Looking
closer, RegionScannerImpl#isFilterDone is only true when the RegionScanner
wants to indicate that the entire scan should stop (i.e. the client shouldn't
even try to change regions, the whole scan is done).
So to be clear, it looks as though the moreResults flag is false ONLY when the
entire scan needs to stop, NOT when a region is exhausted. The net effect is
that moreResults will always appear to be true client side, even when the
region is exhausted. Thus, I think we will still end up making that extra RPC
that Lars mentioned above in order to see that the Result[] is empty and thus
the region is exhausted, before the region change occurs.
Since moreResults is a flag that is used for global scan logic (logic not
specific to a particular region), I think we need to introduce a new flag that
is specific to the region's results. If the result size limit or caching limit
is reached inside RSRpcServices, return true, else false.
bq. // Server didn't respond whether it has more results or not.
Is it possible here that we may inadvertently interpret the missing flag as
meaning the region is exhausted? Probably fine because the limit logic is still
in the ClientScanner while condition, just wondering.
> ResultScanner doesn't return all rows in Scan
> ---------------------------------------------
>
> Key: HBASE-13262
> URL: https://issues.apache.org/jira/browse/HBASE-13262
> Project: HBase
> Issue Type: Bug
> Components: Client
> Affects Versions: 2.0.0, 1.1.0
> Environment: Single node, pseduo-distributed 1.1.0-SNAPSHOT
> Reporter: Josh Elser
> Assignee: Josh Elser
> Priority: Blocker
> Fix For: 2.0.0, 1.1.0, 0.98.13
>
> Attachments: 13262-0.98-testpatch.txt, HBASE-13262-branch-1-v2.patch,
> HBASE-13262-branch-1.patch, HBASE-13262-v1.patch, HBASE-13262-v2.patch,
> HBASE-13262.patch, regionserver-logging.diff, testrun_0.98.txt,
> testrun_branch1.0.txt
>
>
> Tried to write a simple Java client again 1.1.0-SNAPSHOT.
> * Write 1M rows, each row with 1 family, and 10 qualifiers (values [0-9]),
> for a total of 10M cells written
> * Read back the data from the table, ensure I saw 10M cells
> Running it against {{04ac1891}} (and earlier) yesterday, I would get ~20% of
> the actual rows. Running against 1.0.0, returns all 10M records as expected.
> [Code I was
> running|https://github.com/joshelser/hbase-hwhat/blob/master/src/main/java/hbase/HBaseTest.java]
> for the curious.
--
This message was sent by Atlassian JIRA
(v6.3.4#6332)
