From 5b0abbf48af01c8df831c2968c05d9a4df31a791 Mon Sep 17 00:00:00 2001 From: happenlee Date: Tue, 22 Sep 2026 15:45:27 +0800 Subject: [PATCH] [improvement](fe) Adjust scanner defaults for branch-4.2 ### What problem does this PR solve? Issue Number: None Related PR: #68374, #63389, #65263 Problem Summary: On branch-4.2, sessions currently default to `min_scanners_concurrency = 1` and `enable_expr_zonemap_filter = false`. Set these defaults to `4` and `true`, respectively, and update the English and Chinese session-variable descriptions. This enables the existing expression ZoneMap filtering path by default and raises the minimum scanner concurrency under the existing scanner-count, concurrency and memory limits. Serial scans continue to use one scanner. Both variables remain configurable through the existing session/global settings and are already forwarded to BE. ### Release note Enable expression ZoneMap filtering by default and increase the default `min_scanners_concurrency` from `1` to `4`. ### Check List (For Author) - Test: FE unit tests and Checkstyle passed. - `MAVEN_ARGS='-T 48' bash run-fe-ut.sh --run org.apache.doris.qe.SessionVariablesTest,org.apache.doris.qe.VariableMgrTest`: 29 tests, 0 failures/errors/skips. - `mvn -T 48 checkstyle:check -pl fe-core` (from `fe/`): 0 violations. - `git diff --check`: passed. - Behavior changed: Yes. The two session defaults change as described above. - Does this need documentation: No. Both session-variable descriptions are updated. --- .../main/java/org/apache/doris/qe/SessionVariable.java | 10 +++++----- 1 file changed, 5 insertions(+), 5 deletions(-) diff --git a/fe/fe-core/src/main/java/org/apache/doris/qe/SessionVariable.java b/fe/fe-core/src/main/java/org/apache/doris/qe/SessionVariable.java index 0c099760736e5c..2c97642435b2d2 100644 --- a/fe/fe-core/src/main/java/org/apache/doris/qe/SessionVariable.java +++ b/fe/fe-core/src/main/java/org/apache/doris/qe/SessionVariable.java @@ -1156,9 +1156,9 @@ public static double getHotValueThreshold() { public int localExchangeFreeBlocksLimit = 4; @VariableMgr.VarAttr(name = MIN_SCANNERS_CONCURRENCY, needForward = true, description = { - "Scanner 的最小并发度，默认为 1", "The min concurrency of Scanner, default 1" + "Scanner 的最小并发度，默认为 4", "The min concurrency of Scanner, default 4" }) - public int minScannersConcurrency = 1; + public int minScannersConcurrency = 4; @VariableMgr.VarAttr(name = MIN_FILE_SCANNERS_CONCURRENCY, needForward = true, description = { "外表 Scanner 的最小并发度，默认为 1", "The min concurrency of Remote Scanner, default 1" @@ -2779,12 +2779,12 @@ public Map getForceEagerAggHintMap() { name = ENABLE_EXPR_ZONEMAP_FILTER, fuzzy = true, description = {"控制支持该变量的 scanner 是否启用表达式 ZoneMap 过滤。" - + "File Scanner V2 始终启用安全的表达式 ZoneMap 过滤。默认为 false。", + + "File Scanner V2 始终启用安全的表达式 ZoneMap 过滤。默认为 true。", "Controls expression ZoneMap filtering in scanners that honor this variable. " + "File Scanner V2 always enables safe expression ZoneMap filtering. " - + "The default value is false."}, + + "The default value is true."}, needForward = true) - public boolean enableExprZonemapFilter = false; + public boolean enableExprZonemapFilter = true; @VariableMgr.VarAttr( name = CHECK_ORC_INIT_SARGS_SUCCESS,