This was cross-posted to
https://community.cloudera.com/t5/Interactive-Short-cycle-SQL/inconsistent-metadata-between-impala-daemons-in-5-15/m-p/91573#M5712%3Feid=1&aid=1

On Wed, Jun 12, 2019 at 3:48 PM Sunil Parmar <[email protected]> wrote:

> Thanks, SYNC_DDL should help! Is there a way to check if one node has out
> of sync metadata ?
>
> Sunil Parmar
>
>
> On Wed, Jun 12, 2019 at 7:49 AM Csaba Ringhofer <[email protected]>
> wrote:
>
>> >We tried invalidating metadata ( followed by 'describe table' to fix
>> metadata) but it didn't help. Even re-running refresh doesn't help all the
>> time. We need some help/points to figure out the issue.
>> Did you to this on the node with the stale metadata, or on another one?
>>
>> It is normal that some nodes have stale metadata for some time after
>> REFRESH was run on another node, unless query option SYNC_DDL=1.
>> SYNC_DDL was introduced to force DDL/DML operations to wait until the
>> metadata changes are broadcast to all nodes (by statestored). If SYNC_DDL=0
>> (default), then REFRESH TABLE can return before all nodes are updated.
>>
>> Can you try SET SYNC_DDL=1; before REFRESH TABLE?
>>
>>
>>
>> On Wed, Jun 12, 2019 at 7:37 AM Sunil Parmar <[email protected]>
>> wrote:
>>
>>> Impala version : impalad version 2.12.0
>>> OS: Centos 6.10
>>> Table size : 88TB
>>> Partitions : 7K
>>> Type : Parquet, file size compacted 256MB
>>>
>>>
>>> We ingest data every minute to the table partition and run the refresh
>>> table to load the data. There is a separate compaction process that runs
>>> every hour and merges smaller files into big. The set up was working fine
>>> for months until recently we are running into a strange issue of
>>> inconsistent behavior between few nodes. Randomly some nodes appear to have
>>> inconsistent metadata i.e. even though refresh table command ran
>>> successfully some nodes still didn't have correct files so they referred
>>> older files for those partitions.
>>>
>>> We tried invalidating metadata ( followed by 'describe table' to fix
>>> metadata) but it didn't help. Even re-running refresh doesn't help all the
>>> time. We need some help/points to figure out the issue.
>>>
>>> * Is there a way to check if all Impala nodes have stale metadata?
>>> * How to fix metadata for individual node? Is there a command?
>>> * Anyone has faced similar issue? Can you share your experience and fix?
>>>
>>> Sunil Parmar
>>>
>>

Reply via email to