[
https://issues.apache.org/jira/browse/IMPALA-4233?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=16840840#comment-16840840
]
Tim Armstrong commented on IMPALA-4233:
---------------------------------------
I think the below commit solved some subset of these issues (or at least moved
around the problem):
commit d4648e87b4bc0c05203f6af0f4448dc2017bda80
Author: Tim Armstrong <[email protected]>
Date: Fri Mar 15 09:58:39 2019 -0700
IMPALA-4356,IMPALA-7331: codegen all ScalarExprs
Based on initial draft patch by Pooja Nilangekar.
Codegen'd expressions can be executed in two ways - either by
being called directly from a fully codegend function, or from
interpreted code via a function pointer (previously
ScalarFnCall::scalar_fn_wrapper_).
This change moves the function pointer from ScalarFnCall to its
base class ScalarExpr, so the full expr tree can be codegen'd, not
just the ScalarFnCall subtrees. The key refactoring and improvements
are:
* ScalarExpr::Get*Val() switches between interpreted and the codegen'd
function pointer code paths in an inline function, avoiding a
virtual function call to ScalarFnCal::Get*Val().
* Boilerplate logic is moved to ScalarExpr::GetCodegendComputeFn(),
which calls a virtual function GetCodegenComputeFnImpl().
* ScalarFnCall's logic for deciding whether to interpret or codegen is
better abstracted and exposed to ScalarExpr as IsInterpretable()
and ShouldCodegen() methods.
* The ScalarExpr::codegend_compute_fn_ function pointer is only
populated for expressions that are "codegen entry points". These
include the roots of expr trees and non-root expressions
where the parent expression calls Get*Val() from the
pseudo-codegend GetCodegendComputeFnWrapper().
* ScalarFnCall is always initialised for interpreted execution.
Otherwise the function pointer is needed for non-root expressions,
e.g. to support ScalarExprEvaluator::GetConstantVal().
* Latent bugs/gaps for codegen of CollectionVal are fixed. CollectionVal
is modified to use the StringVal memory layout to allow code sharing
with StringVal. These fixes allowed simplification of
IsNotEmptyPredicate codegen (from IMPALA-7657).
I chose to tackle two problems in one change - adding support for
generating codegen'd function pointers for all ScalarExprs, and adding
the "entry point" concept - to avoid a blow-up in the number of
codegen'd entry points that could lead to longer codegen times and/or
worse code because of inlining changes.
IMPALA-7331 (CHAR codegen support functions) is also fixed because
it was simpler to enable CHAR codegen within ScalarExpr than to carry
forward the exiting CHAR workarounds from ScalarFnCall. The
CHAR-specific codegen support required in the scalar expr subsystem is
very limited. StringVal intermediates are used everywhere. Only
SlotRef actually operates on the different tuple layout, and the
required codegen support for SlotRef already exists for UDA
intermediates anyway.
Testing:
* Ran exhaustive tests.
Perf:
* Ran a basic insert benchmark, which went from 10.1s to 7.6s
create table foo stored as parquet as
select case when l_orderkey % 2 = 0 then 'aaa' else 'bbb' end
from tpch30_parquet.lineitem;
* Ran a basic CHAR expr test:
set num_nodes=1;
set mt_dop=1;
select count(*) from lineitem
where cast(l_linestatus as CHAR(2)) = 'O ' and
cast(l_returnflag as CHAR(2)) = 'N '
The time spent in the scan went from 520ms to 220ms.
* Added perf regression test to tpcds-insert, similar to the manual
benchmark.
* Ran single-node TPC-H with large and small scale factors, to estimate
impact on execution perf and query startup time, respectively.
+----------+-----------------------+---------+------------+------------+----------------+
| Workload | File Format | Avg (s) | Delta(Avg) | GeoMean(s) |
Delta(GeoMean) |
+----------+-----------------------+---------+------------+------------+----------------+
| TPCH(30) | parquet / none / none | 6.84 | -0.18% | 4.49 |
-0.31% |
+----------+-----------------------+---------+------------+------------+----------------+
+----------+----------+-----------------------+--------+-------------+------------+-----------+----------------+-------+----------------+---------+--------+
| Workload | Query | File Format | Avg(s) | Base Avg(s) |
Delta(Avg) | StdDev(%) | Base StdDev(%) | Iters | Median Diff(%) | MW Zval |
Tval |
+----------+----------+-----------------------+--------+-------------+------------+-----------+----------------+-------+----------------+---------+--------+
| TPCH(30) | TPCH-Q20 | parquet / none / none | 2.58 | 2.47 |
+4.18% | 1.29% | 0.88% | 5 | +4.12% | 2.31 | 5.81
|
| TPCH(30) | TPCH-Q17 | parquet / none / none | 4.81 | 4.61 |
+4.33% | 2.18% | 2.15% | 5 | +3.91% | 1.73 | 3.09
|
| TPCH(30) | TPCH-Q21 | parquet / none / none | 26.45 | 26.16 |
+1.09% | 0.37% | 0.50% | 5 | +1.36% | 2.02 | 3.94
|
| TPCH(30) | TPCH-Q9 | parquet / none / none | 15.92 | 15.75 |
+1.09% | 2.87% | 1.65% | 5 | +0.88% | 0.29 | 0.73
|
| TPCH(30) | TPCH-Q12 | parquet / none / none | 2.38 | 2.35 |
+1.12% | 1.64% | 1.11% | 5 | +0.80% | 1.15 | 1.26
|
| TPCH(30) | TPCH-Q14 | parquet / none / none | 2.94 | 2.91 |
+1.13% | 7.68% | 5.37% | 5 | -0.34% | -0.29 | 0.27
|
| TPCH(30) | TPCH-Q18 | parquet / none / none | 18.10 | 18.02 |
+0.42% | 2.70% | 0.56% | 5 | +0.28% | 0.29 | 0.34
|
| TPCH(30) | TPCH-Q8 | parquet / none / none | 4.72 | 4.72 |
-0.04% | 1.20% | 1.65% | 5 | +0.05% | 0.00 |
-0.04 |
| TPCH(30) | TPCH-Q19 | parquet / none / none | 3.92 | 3.93 |
-0.26% | 1.08% | 2.36% | 5 | +0.20% | 0.58 |
-0.23 |
| TPCH(30) | TPCH-Q6 | parquet / none / none | 1.27 | 1.27 |
-0.28% | 0.22% | 0.88% | 5 | +0.09% | 0.29 |
-0.68 |
| TPCH(30) | TPCH-Q16 | parquet / none / none | 2.64 | 2.65 |
-0.45% | 1.65% | 0.65% | 5 | -0.24% | -0.58 |
-0.57 |
| TPCH(30) | TPCH-Q22 | parquet / none / none | 3.10 | 3.13 |
-0.76% | 1.47% | 1.12% | 5 | -0.21% | -0.29 |
-0.93 |
| TPCH(30) | TPCH-Q2 | parquet / none / none | 1.20 | 1.21 |
-0.80% | 2.26% | 2.47% | 5 | -0.82% | -1.15 |
-0.53 |
| TPCH(30) | TPCH-Q4 | parquet / none / none | 1.97 | 1.99 |
-1.37% | 1.84% | 3.21% | 5 | -0.47% | -0.58 |
-0.83 |
| TPCH(30) | TPCH-Q13 | parquet / none / none | 11.53 | 11.63 |
-0.91% | 0.46% | 0.49% | 5 | -0.95% | -2.02 |
-3.08 |
| TPCH(30) | TPCH-Q10 | parquet / none / none | 5.13 | 5.21 |
-1.51% | 2.24% | 4.05% | 5 | -0.94% | -0.58 |
-0.73 |
| TPCH(30) | TPCH-Q5 | parquet / none / none | 3.61 | 3.66 |
-1.40% | 0.66% | 0.79% | 5 | -1.33% | -1.73 |
-3.05 |
| TPCH(30) | TPCH-Q7 | parquet / none / none | 19.42 | 19.71 |
-1.52% | 1.34% | 1.39% | 5 | -1.22% | -1.44 |
-1.76 |
| TPCH(30) | TPCH-Q3 | parquet / none / none | 5.08 | 5.15 |
-1.49% | 1.34% | 0.73% | 5 | -1.35% | -1.44 |
-2.20 |
| TPCH(30) | TPCH-Q15 | parquet / none / none | 3.42 | 3.49 |
-1.92% | 0.93% | 1.47% | 5 | -1.53% | -1.15 |
-2.49 |
| TPCH(30) | TPCH-Q11 | parquet / none / none | 1.15 | 1.19 |
-3.17% | 2.27% | 1.95% | 5 | -4.21% | -1.15 |
-2.41 |
| TPCH(30) | TPCH-Q1 | parquet / none / none | 9.26 | 9.63 |
-3.85% | 0.62% | 0.59% | 5 | -3.78% | -2.31 |
-10.25 |
+----------+----------+-----------------------+--------+-------------+------------+-----------+----------------+-------+----------------+---------+--------+
Cluster Name: UNKNOWN
Lab Run Info: UNKNOWN
Impala Version: impalad version 3.2.0-SNAPSHOT RELEASE ()
Baseline Impala Version: impalad version 3.2.0-SNAPSHOT RELEASE (2019-03-19)
+----------+-----------------------+---------+------------+------------+----------------+
| Workload | File Format | Avg (s) | Delta(Avg) | GeoMean(s) |
Delta(GeoMean) |
+----------+-----------------------+---------+------------+------------+----------------+
| TPCH(2) | parquet / none / none | 0.90 | -0.08% | 0.80 |
-0.05% |
+----------+-----------------------+---------+------------+------------+----------------+
+----------+----------+-----------------------+--------+-------------+------------+-----------+----------------+-------+----------------+---------+-------+
| Workload | Query | File Format | Avg(s) | Base Avg(s) |
Delta(Avg) | StdDev(%) | Base StdDev(%) | Iters | Median Diff(%) | MW Zval |
Tval |
+----------+----------+-----------------------+--------+-------------+------------+-----------+----------------+-------+----------------+---------+-------+
| TPCH(2) | TPCH-Q18 | parquet / none / none | 1.22 | 1.19 |
+1.93% | 3.81% | 4.46% | 20 | +3.34% | 1.62 | 1.46
|
| TPCH(2) | TPCH-Q10 | parquet / none / none | 0.74 | 0.73 |
+1.97% | 3.36% | 2.94% | 20 | +0.97% | 1.88 | 1.95
|
| TPCH(2) | TPCH-Q11 | parquet / none / none | 0.49 | 0.48 |
+1.91% | 6.19% | 4.64% | 20 | +0.25% | 0.95 | 1.09
|
| TPCH(2) | TPCH-Q4 | parquet / none / none | 0.43 | 0.43 |
+1.99% | 6.26% | 5.86% | 20 | +0.15% | 0.92 | 1.03
|
| TPCH(2) | TPCH-Q15 | parquet / none / none | 0.50 | 0.49 |
+1.82% | 7.32% | 6.35% | 20 | +0.26% | 1.01 | 0.83
|
| TPCH(2) | TPCH-Q1 | parquet / none / none | 0.98 | 0.97 |
+0.79% | 4.64% | 2.73% | 20 | +0.36% | 0.77 | 0.65
|
| TPCH(2) | TPCH-Q19 | parquet / none / none | 0.83 | 0.83 |
+0.65% | 3.33% | 2.80% | 20 | +0.44% | 2.18 | 0.67
|
| TPCH(2) | TPCH-Q14 | parquet / none / none | 0.62 | 0.62 |
+0.97% | 2.86% | 1.00% | 20 | +0.04% | 0.13 | 1.42
|
| TPCH(2) | TPCH-Q3 | parquet / none / none | 0.88 | 0.87 |
+0.57% | 2.17% | 1.74% | 20 | +0.29% | 1.15 | 0.92
|
| TPCH(2) | TPCH-Q12 | parquet / none / none | 0.53 | 0.53 |
+0.27% | 4.58% | 5.78% | 20 | +0.46% | 1.47 | 0.16
|
| TPCH(2) | TPCH-Q17 | parquet / none / none | 0.72 | 0.72 |
+0.15% | 3.64% | 5.55% | 20 | +0.21% | 0.86 | 0.10
|
| TPCH(2) | TPCH-Q21 | parquet / none / none | 2.05 | 2.05 |
+0.21% | 1.99% | 2.37% | 20 | +0.01% | 0.25 | 0.30
|
| TPCH(2) | TPCH-Q5 | parquet / none / none | 1.28 | 1.27 |
+0.24% | 1.61% | 1.80% | 20 | -0.02% | -0.57 | 0.44
|
| TPCH(2) | TPCH-Q13 | parquet / none / none | 1.27 | 1.27 |
-0.34% | 1.69% | 1.83% | 20 | -0.20% | -1.65 |
-0.61 |
| TPCH(2) | TPCH-Q7 | parquet / none / none | 1.72 | 1.73 |
-0.55% | 2.40% | 1.69% | 20 | -0.03% | -0.42 |
-0.83 |
| TPCH(2) | TPCH-Q8 | parquet / none / none | 1.27 | 1.28 |
-0.68% | 3.10% | 3.89% | 20 | -0.06% | -0.54 |
-0.62 |
| TPCH(2) | TPCH-Q6 | parquet / none / none | 0.36 | 0.36 |
-0.84% | 0.79% | 3.51% | 20 | -0.07% | -0.36 |
-1.04 |
| TPCH(2) | TPCH-Q2 | parquet / none / none | 0.65 | 0.65 |
-1.17% | 4.76% | 5.99% | 20 | -0.05% | -0.25 |
-0.69 |
| TPCH(2) | TPCH-Q9 | parquet / none / none | 1.59 | 1.62 |
-2.01% | 1.45% | 5.12% | 20 | -0.16% | -1.24 |
-1.69 |
| TPCH(2) | TPCH-Q20 | parquet / none / none | 0.68 | 0.69 |
-1.73% | 4.35% | 4.43% | 20 | -0.49% | -1.74 |
-1.25 |
| TPCH(2) | TPCH-Q22 | parquet / none / none | 0.38 | 0.40 |
-2.89% | 7.42% | 6.39% | 20 | -0.21% | -0.66 |
-1.34 |
| TPCH(2) | TPCH-Q16 | parquet / none / none | 0.59 | 0.62 |
-4.01% | 6.33% | 5.83% | 20 | -4.72% | -1.39 |
-2.13 |
+----------+----------+-----------------------+--------+-------------+------------+-----------+----------------+-------+----------------+---------+-------+
Change-Id: I839d7a3a2f5e1309c33a1f66013ef11628c5dc11
Reviewed-on: http://gerrit.cloudera.org:8080/12797
Reviewed-by: Impala Public Jenkins <[email protected]>
Tested-by: Impala Public Jenkins <[email protected]>
commit 8c5d4e25708356ea84d504d8b0286bd5f165f2e9
Author: Alex Rodoni <[email protected]>
Date: Fri May 10 14:53:57 2019 -0700
IMPALA-8424: [DOCS] Support for column-level permissions on views
Change-Id: I7f95b37891b618b71460cd2ad444a422371455a6
Reviewed-on: http://gerrit.cloudera.org:8080/13310
Reviewed-by: Fredy Wijaya <[email protected]>
Tested-by: Impala Public Jenkins <[email protected]>
> Revisit handling of expr codegen failures
> -----------------------------------------
>
> Key: IMPALA-4233
> URL: https://issues.apache.org/jira/browse/IMPALA-4233
> Project: IMPALA
> Issue Type: Improvement
> Components: Backend
> Affects Versions: Impala 2.8.0
> Reporter: bharath v
> Assignee: Michael Ho
> Priority: Minor
> Labels: codegen
>
> FragmentInstanceState::Open() can fail if codegen of expressions fails:
> {code}
> // It shouldn't be fatal to fail codegen. However, until IMPALA-4233 is
> fixed,
> // ScalarFnCall has no fall back to interpretation when codegen fails
> so propagates
> // the error status for now.
> RETURN_IF_ERROR(runtime_state_->CodegenScalarFns());
> {code}
> In principle many functions can be executed without codegen
--
This message was sent by Atlassian JIRA
(v7.6.3#76005)
---------------------------------------------------------------------
To unsubscribe, e-mail: [email protected]
For additional commands, e-mail: [email protected]
