[jira] [Commented] (HIVE-4897) Hive should handle AlreadyExists on retries when creating tables/partitions
[
https://issues.apache.org/jira/browse/HIVE-4897?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel=17087746#comment-17087746
]
David Mollitor commented on HIVE-4897:
--
I think this is often achieved with an 'updated' timestamp value in the
database schema. When a request is generated, the client puts in a timestamp.
If the operation fails and is re-submitted, if the 'updated' timestamp matches
the requests then a success is returned, otherwise, if the timestamp in HMS is
older, than the retry happens again.
> Hive should handle AlreadyExists on retries when creating tables/partitions
> ---
>
> Key: HIVE-4897
> URL: https://issues.apache.org/jira/browse/HIVE-4897
> Project: Hive
> Issue Type: Bug
>Reporter: Sergey Shelukhin
>Assignee: Aihua Xu
>Priority: Major
> Attachments: hive-snippet.log
>
>
> Creating new tables/partitions may fail with an AlreadyExistsException if
> there is an error part way through the creation and the HMS tries again
> without properly cleaning up or checking if this is a retry.
> While partitioning a new table via a script on distributed hive (MetaStore on
> the same machine) there was a long timeout and then:
> {code}
> FAILED: Execution Error, return code 1 from
> org.apache.hadoop.hive.ql.exec.DDLTask.
> AlreadyExistsException(message:Partition already exists:Partition( ...
> {code}
> I am assuming this is due to retry. Perhaps already-exists on retry could be
> handled better.
> A similar error occurred while creating a table through Impala, which issued
> a single createTable call that failed with an AlreadyExistsException. See the
> logs related to table tmp_proc_8_d2b7b0f133be455ca95615818b8a5879_7 in the
> attached hive-snippet.log
--
This message was sent by Atlassian Jira
(v8.3.4#803005)
[jira] [Commented] (HIVE-4897) Hive should handle AlreadyExists on retries when creating tables/partitions
[
https://issues.apache.org/jira/browse/HIVE-4897?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel=15178474#comment-15178474
]
Sergey Shelukhin commented on HIVE-4897:
I think the simplest path of the approach outlined above will work. I've done
similar work in HBase to make increment operation retries idempotent (so the
requirements were more stringent and tokens actually needed to survive restarts
and failover), and it was pretty manageable. With relaxed requirements like no
persistence it should be simpler still.
> Hive should handle AlreadyExists on retries when creating tables/partitions
> ---
>
> Key: HIVE-4897
> URL: https://issues.apache.org/jira/browse/HIVE-4897
> Project: Hive
> Issue Type: Bug
>Reporter: Sergey Shelukhin
>Assignee: Aihua Xu
> Attachments: HIVE-4897.patch, hive-snippet.log
>
>
> Creating new tables/partitions may fail with an AlreadyExistsException if
> there is an error part way through the creation and the HMS tries again
> without properly cleaning up or checking if this is a retry.
> While partitioning a new table via a script on distributed hive (MetaStore on
> the same machine) there was a long timeout and then:
> {code}
> FAILED: Execution Error, return code 1 from
> org.apache.hadoop.hive.ql.exec.DDLTask.
> AlreadyExistsException(message:Partition already exists:Partition( ...
> {code}
> I am assuming this is due to retry. Perhaps already-exists on retry could be
> handled better.
> A similar error occurred while creating a table through Impala, which issued
> a single createTable call that failed with an AlreadyExistsException. See the
> logs related to table tmp_proc_8_d2b7b0f133be455ca95615818b8a5879_7 in the
> attached hive-snippet.log
--
This message was sent by Atlassian JIRA
(v6.3.4#6332)
[jira] [Commented] (HIVE-4897) Hive should handle AlreadyExists on retries when creating tables/partitions
[
https://issues.apache.org/jira/browse/HIVE-4897?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel=15177849#comment-15177849
]
Aihua Xu commented on HIVE-4897:
Yeah. That scenario definitely will cause the issue, but should be rare? What
we have seen seems to be caused by unsafe concurrent HMS access, which seems to
be fixed.
Let me investigate further how to completely fix this issue including the cases
you mentioned.
> Hive should handle AlreadyExists on retries when creating tables/partitions
> ---
>
> Key: HIVE-4897
> URL: https://issues.apache.org/jira/browse/HIVE-4897
> Project: Hive
> Issue Type: Bug
>Reporter: Sergey Shelukhin
>Assignee: Aihua Xu
> Attachments: HIVE-4897.patch, hive-snippet.log
>
>
> Creating new tables/partitions may fail with an AlreadyExistsException if
> there is an error part way through the creation and the HMS tries again
> without properly cleaning up or checking if this is a retry.
> While partitioning a new table via a script on distributed hive (MetaStore on
> the same machine) there was a long timeout and then:
> {code}
> FAILED: Execution Error, return code 1 from
> org.apache.hadoop.hive.ql.exec.DDLTask.
> AlreadyExistsException(message:Partition already exists:Partition( ...
> {code}
> I am assuming this is due to retry. Perhaps already-exists on retry could be
> handled better.
> A similar error occurred while creating a table through Impala, which issued
> a single createTable call that failed with an AlreadyExistsException. See the
> logs related to table tmp_proc_8_d2b7b0f133be455ca95615818b8a5879_7 in the
> attached hive-snippet.log
--
This message was sent by Atlassian JIRA
(v6.3.4#6332)
[jira] [Commented] (HIVE-4897) Hive should handle AlreadyExists on retries when creating tables/partitions
[
https://issues.apache.org/jira/browse/HIVE-4897?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel=15176759#comment-15176759
]
Sergey Shelukhin commented on HIVE-4897:
I've seen this error fairly recently. It happens if the response was not
delivered to client due to a network problem (or theoretically due to timing
issue with retry it can also happen, if the retry is done after timeout but
before the corresponding timeout on the server, and the original request
finishes before the retry is processed.
I've also seen it happen when the connection to underlying DB was lost in
commitTxn, but the commit still happened (that one time was due to BoneCP
connection-closing bug, but it could presumably also happen because of a
connection issue). commitTxn fails, but the table is already created.
> Hive should handle AlreadyExists on retries when creating tables/partitions
> ---
>
> Key: HIVE-4897
> URL: https://issues.apache.org/jira/browse/HIVE-4897
> Project: Hive
> Issue Type: Bug
>Reporter: Sergey Shelukhin
>Assignee: Aihua Xu
> Attachments: HIVE-4897.patch, hive-snippet.log
>
>
> Creating new tables/partitions may fail with an AlreadyExistsException if
> there is an error part way through the creation and the HMS tries again
> without properly cleaning up or checking if this is a retry.
> While partitioning a new table via a script on distributed hive (MetaStore on
> the same machine) there was a long timeout and then:
> {code}
> FAILED: Execution Error, return code 1 from
> org.apache.hadoop.hive.ql.exec.DDLTask.
> AlreadyExistsException(message:Partition already exists:Partition( ...
> {code}
> I am assuming this is due to retry. Perhaps already-exists on retry could be
> handled better.
> A similar error occurred while creating a table through Impala, which issued
> a single createTable call that failed with an AlreadyExistsException. See the
> logs related to table tmp_proc_8_d2b7b0f133be455ca95615818b8a5879_7 in the
> attached hive-snippet.log
--
This message was sent by Atlassian JIRA
(v6.3.4#6332)
[jira] [Commented] (HIVE-4897) Hive should handle AlreadyExists on retries when creating tables/partitions
[
https://issues.apache.org/jira/browse/HIVE-4897?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel=15176132#comment-15176132
]
Aihua Xu commented on HIVE-4897:
[~sershe] Do you still notice the issue happens? I guess we may not have this
issue anymore since before we have unsafe concurrent access to the HMS clients
which could lead to this error.
I went through the code, if some error happens when we create table or
partitions, it should roll back properly. Let me know your thoughts.
> Hive should handle AlreadyExists on retries when creating tables/partitions
> ---
>
> Key: HIVE-4897
> URL: https://issues.apache.org/jira/browse/HIVE-4897
> Project: Hive
> Issue Type: Bug
>Reporter: Sergey Shelukhin
>Assignee: Aihua Xu
> Attachments: HIVE-4897.patch, hive-snippet.log
>
>
> Creating new tables/partitions may fail with an AlreadyExistsException if
> there is an error part way through the creation and the HMS tries again
> without properly cleaning up or checking if this is a retry.
> While partitioning a new table via a script on distributed hive (MetaStore on
> the same machine) there was a long timeout and then:
> {code}
> FAILED: Execution Error, return code 1 from
> org.apache.hadoop.hive.ql.exec.DDLTask.
> AlreadyExistsException(message:Partition already exists:Partition( ...
> {code}
> I am assuming this is due to retry. Perhaps already-exists on retry could be
> handled better.
> A similar error occurred while creating a table through Impala, which issued
> a single createTable call that failed with an AlreadyExistsException. See the
> logs related to table tmp_proc_8_d2b7b0f133be455ca95615818b8a5879_7 in the
> attached hive-snippet.log
--
This message was sent by Atlassian JIRA
(v6.3.4#6332)
[jira] [Commented] (HIVE-4897) Hive should handle AlreadyExists on retries when creating tables/partitions
[
https://issues.apache.org/jira/browse/HIVE-4897?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel=15144740#comment-15144740
]
Aihua Xu commented on HIVE-4897:
[~sershe] I haven't been able to work on that yet. Feel free to work on it if
you have any idea.
> Hive should handle AlreadyExists on retries when creating tables/partitions
> ---
>
> Key: HIVE-4897
> URL: https://issues.apache.org/jira/browse/HIVE-4897
> Project: Hive
> Issue Type: Bug
>Reporter: Sergey Shelukhin
>Assignee: Aihua Xu
> Attachments: HIVE-4897.patch, hive-snippet.log
>
>
> Creating new tables/partitions may fail with an AlreadyExistsException if
> there is an error part way through the creation and the HMS tries again
> without properly cleaning up or checking if this is a retry.
> While partitioning a new table via a script on distributed hive (MetaStore on
> the same machine) there was a long timeout and then:
> {code}
> FAILED: Execution Error, return code 1 from
> org.apache.hadoop.hive.ql.exec.DDLTask.
> AlreadyExistsException(message:Partition already exists:Partition( ...
> {code}
> I am assuming this is due to retry. Perhaps already-exists on retry could be
> handled better.
> A similar error occurred while creating a table through Impala, which issued
> a single createTable call that failed with an AlreadyExistsException. See the
> logs related to table tmp_proc_8_d2b7b0f133be455ca95615818b8a5879_7 in the
> attached hive-snippet.log
--
This message was sent by Atlassian JIRA
(v6.3.4#6332)
[jira] [Commented] (HIVE-4897) Hive should handle AlreadyExists on retries when creating tables/partitions
[
https://issues.apache.org/jira/browse/HIVE-4897?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel=15143569#comment-15143569
]
Sergey Shelukhin commented on HIVE-4897:
I think the simplest solution is actually to have a 2pc-like protocol, where
first the operation will get a token from metastore. The tokens can be stored
in memory and are unique (an incrementing number), they are GCed after a long
period (an hour?). Then each operation with the token would have a
client-maintained sequence number that is not incremented on retries (for
generality; or just one expected operation to start, which would be good enough
for this case) would record success for the token.
If a retry comes with the same token(+seq num in case of multiple ops), it
would be a no-op.
Comparing objects as originally suggested is both difficult and error-prone,
and also not bullet-proof if someone alters the objects in the interim.
This approach is hard to use for ops that return result because it's not clear
what result is to be returned, unless the result of original operation is
saved, which is a PITA. We can either throw a special exception (succeeded, but
cannot return the result), or return the latest state of the object for some
ops; create* do not return any result so we are good here.
Tokens can be stored externally for failover, but I don't think this is really
necessary for the first draft.
For the first draft in-memory, single-operation tokens with no result option
would be easy to implement. [~thejas] should we do that? Opinions? Related to
the timeout issue we were discussing.
> Hive should handle AlreadyExists on retries when creating tables/partitions
> ---
>
> Key: HIVE-4897
> URL: https://issues.apache.org/jira/browse/HIVE-4897
> Project: Hive
> Issue Type: Bug
>Reporter: Sergey Shelukhin
>Assignee: Aihua Xu
> Attachments: HIVE-4897.patch, hive-snippet.log
>
>
> Creating new tables/partitions may fail with an AlreadyExistsException if
> there is an error part way through the creation and the HMS tries again
> without properly cleaning up or checking if this is a retry.
> While partitioning a new table via a script on distributed hive (MetaStore on
> the same machine) there was a long timeout and then:
> {code}
> FAILED: Execution Error, return code 1 from
> org.apache.hadoop.hive.ql.exec.DDLTask.
> AlreadyExistsException(message:Partition already exists:Partition( ...
> {code}
> I am assuming this is due to retry. Perhaps already-exists on retry could be
> handled better.
> A similar error occurred while creating a table through Impala, which issued
> a single createTable call that failed with an AlreadyExistsException. See the
> logs related to table tmp_proc_8_d2b7b0f133be455ca95615818b8a5879_7 in the
> attached hive-snippet.log
--
This message was sent by Atlassian JIRA
(v6.3.4#6332)
[jira] [Commented] (HIVE-4897) Hive should handle AlreadyExists on retries when creating tables/partitions
[
https://issues.apache.org/jira/browse/HIVE-4897?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanelfocusedCommentId=14662705#comment-14662705
]
Sergey Shelukhin commented on HIVE-4897:
Hmm... wouldn't it just retry after the first exception and then ignore the
repeated exception on retry?
I think it may need to check that the object in question exists for each API
and maybe that it matches the request, on retry.
I am not sure there's good way to add repeatable test for this...
Hive should handle AlreadyExists on retries when creating tables/partitions
---
Key: HIVE-4897
URL: https://issues.apache.org/jira/browse/HIVE-4897
Project: Hive
Issue Type: Bug
Reporter: Sergey Shelukhin
Assignee: Aihua Xu
Attachments: HIVE-4897.patch, hive-snippet.log
Creating new tables/partitions may fail with an AlreadyExistsException if
there is an error part way through the creation and the HMS tries again
without properly cleaning up or checking if this is a retry.
While partitioning a new table via a script on distributed hive (MetaStore on
the same machine) there was a long timeout and then:
{code}
FAILED: Execution Error, return code 1 from
org.apache.hadoop.hive.ql.exec.DDLTask.
AlreadyExistsException(message:Partition already exists:Partition( ...
{code}
I am assuming this is due to retry. Perhaps already-exists on retry could be
handled better.
A similar error occurred while creating a table through Impala, which issued
a single createTable call that failed with an AlreadyExistsException. See the
logs related to table tmp_proc_8_d2b7b0f133be455ca95615818b8a5879_7 in the
attached hive-snippet.log
--
This message was sent by Atlassian JIRA
(v6.3.4#6332)
[jira] [Commented] (HIVE-4897) Hive should handle AlreadyExists on retries when creating tables/partitions
[
https://issues.apache.org/jira/browse/HIVE-4897?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanelfocusedCommentId=14661883#comment-14661883
]
Hive QA commented on HIVE-4897:
---
{color:red}Overall{color}: -1 no tests executed
Here are the results of testing the latest attachment:
https://issues.apache.org/jira/secure/attachment/12749104/HIVE-4897.patch
Test results:
http://ec2-174-129-184-35.compute-1.amazonaws.com/jenkins/job/PreCommit-HIVE-TRUNK-Build/4859/testReport
Console output:
http://ec2-174-129-184-35.compute-1.amazonaws.com/jenkins/job/PreCommit-HIVE-TRUNK-Build/4859/console
Test logs:
http://ec2-174-129-184-35.compute-1.amazonaws.com/logs/PreCommit-HIVE-TRUNK-Build-4859/
Messages:
{noformat}
Executing org.apache.hive.ptest.execution.PrepPhase
Executing org.apache.hive.ptest.execution.ExecutionPhase
Tests exited with: ExecutionException: java.util.concurrent.ExecutionException:
java.io.IOException: Error writing to
/data/hive-ptest/working/scratch/hiveptest-TestErrorMsg.sh
{noformat}
This message is automatically generated.
ATTACHMENT ID: 12749104 - PreCommit-HIVE-TRUNK-Build
Hive should handle AlreadyExists on retries when creating tables/partitions
---
Key: HIVE-4897
URL: https://issues.apache.org/jira/browse/HIVE-4897
Project: Hive
Issue Type: Bug
Reporter: Sergey Shelukhin
Assignee: Aihua Xu
Attachments: HIVE-4897.patch, hive-snippet.log
Creating new tables/partitions may fail with an AlreadyExistsException if
there is an error part way through the creation and the HMS tries again
without properly cleaning up or checking if this is a retry.
While partitioning a new table via a script on distributed hive (MetaStore on
the same machine) there was a long timeout and then:
{code}
FAILED: Execution Error, return code 1 from
org.apache.hadoop.hive.ql.exec.DDLTask.
AlreadyExistsException(message:Partition already exists:Partition( ...
{code}
I am assuming this is due to retry. Perhaps already-exists on retry could be
handled better.
A similar error occurred while creating a table through Impala, which issued
a single createTable call that failed with an AlreadyExistsException. See the
logs related to table tmp_proc_8_d2b7b0f133be455ca95615818b8a5879_7 in the
attached hive-snippet.log
--
This message was sent by Atlassian JIRA
(v6.3.4#6332)
