IMPALA-8818: Replace deque with spillable queue in BufferedPRS

Replaces DequeRowBatchQueue with SpillableRowBatchQueue in
BufferedPlanRootSink. A few changes to BufferedPlanRootSink were
necessary for it to work with the spillable queue, however, all the
synchronization logic is the same.

SpillableRowBatchQueue is a wrapper around a BufferedTupleStream and
a ReservationManager. It takes in a TBackendResourceProfile that
specifies the max / min memory reservation the BufferedTupleStream can
use to buffer rows. The 'max_unpinned_bytes' parameter limits the max
number of bytes that can be unpinned in the BufferedTupleStream. The
limit is a 'soft' limit because calls to AddBatch may push the amount of
unpinned memory over the limit. The queue is non-blocking and not thread
safe. It provides AddBatch and GetBatch methods. Calls to AddBatch spill
if the BufferedTupleStream does not have enough reservation to fit the
entire RowBatch.

Adds two new query options: 'MAX_PINNED_RESULT_SPOOLING_MEMORY' and
'MAX_UNPINNED_RESULT_SPOOLING_MEMORY', which bound the amount of pinned
and unpinned memory that a query can use for spooling, respectively.
MAX_PINNED_RESULT_SPOOLING_MEMORY must be <=
MAX_UNPINNED_RESULT_SPOOLING_MEMORY in order to allow all the pinned
data in the BufferedTupleStream to be unpinned. This is enforced in a
new method in QueryOptions called 'ValidateQueryOptions'.

Planner Changes:

PlanRootSink.java now computes a full ResourceProfile if result spooling
is enabled. The min mem reservation is bounded by the size of the read and
write pages used by the BufferedTupleStream. The max mem reservation is
bounded by 'MAX_PINNED_RESULT_SPOOLING_MEMORY'. The mem estimate is
computed by estimating the size of the result set using stats.

BufferedTupleStream Re-Factoring:

For the most part, using a BufferedTupleStream outside an ExecNode works
properly. However, some changes were necessary:
* The message for the MAX_ROW_SIZE error is ExecNode specific. In order to
fix this, this patch introduces the concept of an ExecNode 'label' which
is a more generic version of an ExecNode 'id'.
* The definition of TBackendResourceProfile lived in PlanNodes.thrift,
it was moved to its own file so it can be used by DataSinks.thrift.
* Modified BufferedTupleStream so it internally tracks how many bytes
are unpinned (necessary for 'MAX_UNPINNED_RESULT_SPOOLING_MEMORY').

Metrics:
* Added a few of the metrics mentioned in IMPALA-8825 to
BufferedPlanRootSink. Specifically, added timers to track how much time
is spent waiting in the BufferedPlanRootSink 'Send' and 'GetNext'
methods.
* The BufferedTupleStream in the SpillableRowBatchQueue exposes several
BufferPool metrics such as number of reserved and unpinned bytes.

Bug Fixes:
* Fixed a bug in BufferedPlanRootSink where the MemPool used by the
expression evaluators was not being cleared incrementally.
* Fixed a bug where the inactive timer was not being properly updated in
BufferedPlanRootSink.
* Fixed a bug where RowBatch memory was not freed if
BufferedPlanRootSink::GetNext terminated early because it could not
handle requests where num_results < BATCH_SIZE.

Testing:
* Added new tests to test_result_spooling.py.
* Updated errors thrown in spilling-large-rows.test.
* Ran exhaustive tests.

Change-Id: I10f9e72374cdf9501c0e5e2c5b39c13688ae65a9
Reviewed-on: http://gerrit.cloudera.org:8080/14039
Reviewed-by: Sahil Takiar <stakiar@cloudera.com>
Tested-by: Impala Public Jenkins <impala-public-jenkins@cloudera.com>
This commit is contained in:
Sahil Takiar
2019-07-30 08:56:00 -07:00
committed by Impala Public Jenkins
parent af0e04f33b
commit d037ac8304
46 changed files with 995 additions and 268 deletions

View File

@@ -320,8 +320,8 @@ error_codes = (
"Kudu table '$0' column '$1' contains an out of range timestamp. "
"The valid date range is 1400-01-01..9999-12-31."),
("MAX_ROW_SIZE", 104, "Row of size $0 could not be materialized in plan node with "
"id $1. Increase the max_row_size query option (currently $2) to process larger rows."),
("MAX_ROW_SIZE", 104, "Row of size $0 could not be materialized by $1. Increase the "
"max_row_size query option (currently $2) to process larger rows."),
("IR_VERIFY_FAILED", 105,
"Failed to verify generated IR function $0, see log for more details."),