Hi,
we have a very very slow DML Metastore update on simple insert queries into HDFS table (select constant queries). I am not sure if we are hitting https://issues.apache.org/jira/browse/IMPALA-1480, because the table is not partitioned, however I suspect that the number of files under the table can cause the issue (100k+)
After rebuilding the table the DML queries are running fine, is this a known limitation of Impala or a bug?
Thanks
----------------
Max Per-Host Resource Reservation: Memory=0B
Per-Host Resource Estimates: Memory=10.00MB
Codegen disabled by planner
F00:PLAN FRAGMENT [UNPARTITIONED] hosts=1 instances=1
| Per-Host Resources: mem-estimate=48B mem-reservation=0B
WRITE TO HDFS [base.import_processed, OVERWRITE=false]
| partitions=1
| mem-estimate=48B mem-reservation=0B
|
00:UNION
constant-operands=1
mem-estimate=0B mem-reservation=0B
tuple-ids=0 row-size=48B cardinality=1
----------------
Query Timeline
- Query submitted: 0ns (0ns)
- Planning finished: 1ms (1ms)
- Submit for admission: 2ms (1ms)
- Queued: 2ms (0ns)
- Completed admission: 28.64s (28.64s)
- Ready to start on 1 backends: 28.64s (1ms)
- All 1 execution backends (1 fragment instances) started: 28.66s (12ms)
- DML data written: 28.88s (221ms)
- DML Metastore update finished: 3.8m (3.3m)
- Request finished: 3.8m (0ns)
- Unregister query: 3.8m (28ms)