Merge pull request #29565 from vespa-engine/balder/add-use-estimate-for-fetch-postings-flag

Balder/add use estimate for fetch postings flag

20 files changed, 94 insertions, 37 deletions

diff --git a/config-model-api/abi-spec.json b/config-model-api/abi-spec.json
index 81834c5e0cb..8f5d0d37c21 100644
--- a/config-model-api/abi-spec.json
+++ b/config-model-api/abi-spec.json
@@ -1288,7 +1288,8 @@
       "public long mergingMaxMemoryUsagePerNode()",
       "public boolean usePerDocumentThrottledDeleteBucket()",
       "public boolean alwaysMarkPhraseExpensive()",
-      "public boolean createPostinglistWhenNonStrict()"
+      "public boolean createPostinglistWhenNonStrict()",
+      "public boolean useEstimateForFetchPostings()"
     ],
     "fields" : [ ]
   },
diff --git a/config-model-api/src/main/java/com/yahoo/config/model/api/ModelContext.java b/config-model-api/src/main/java/com/yahoo/config/model/api/ModelContext.java
index cb394054510..f34f63a0cfc 100644
--- a/config-model-api/src/main/java/com/yahoo/config/model/api/ModelContext.java
+++ b/config-model-api/src/main/java/com/yahoo/config/model/api/ModelContext.java
@@ -117,6 +117,7 @@ public interface ModelContext {
         @ModelFeatureFlag(owners = {"vekterli"}) default boolean usePerDocumentThrottledDeleteBucket() { return false; }
         @ModelFeatureFlag(owners = {"baldersheim"}) default boolean alwaysMarkPhraseExpensive() { return false; }
         @ModelFeatureFlag(owners = {"baldersheim"}) default boolean createPostinglistWhenNonStrict() { return true; }
+        @ModelFeatureFlag(owners = {"baldersheim"}) default boolean useEstimateForFetchPostings() { return false; }
     }
 
     /** Warning: As elsewhere in this package, do not make backwards incompatible changes that will break old config models! */
diff --git a/config-model/src/main/java/com/yahoo/schema/derived/RawRankProfile.java b/config-model/src/main/java/com/yahoo/schema/derived/RawRankProfile.java
index 411e754f3ef..8090344ea8c 100644
--- a/config-model/src/main/java/com/yahoo/schema/derived/RawRankProfile.java
+++ b/config-model/src/main/java/com/yahoo/schema/derived/RawRankProfile.java
@@ -172,6 +172,7 @@ public class RawRankProfile implements RankProfilesConfig.Producer {
         private final double rankScoreDropLimit;
         private final boolean alwaysMarkPhraseExpensive;
         private final boolean createPostinglistWhenNonStrict;
+        private final boolean useEstimateForFetchPostings;
 
         /**
          * The rank type definitions used to derive settings for the native rank features
@@ -215,6 +216,7 @@ public class RawRankProfile implements RankProfilesConfig.Producer {
             termwiseLimit = compiled.getTermwiseLimit().orElse(deployProperties.featureFlags().defaultTermwiseLimit());
             alwaysMarkPhraseExpensive = deployProperties.featureFlags().alwaysMarkPhraseExpensive();
             createPostinglistWhenNonStrict = deployProperties.featureFlags().createPostinglistWhenNonStrict();
+            useEstimateForFetchPostings = deployProperties.featureFlags().useEstimateForFetchPostings();
             postFilterThreshold = compiled.getPostFilterThreshold();
             approximateThreshold = compiled.getApproximateThreshold();
             targetHitsMaxAdjustmentFactor = compiled.getTargetHitsMaxAdjustmentFactor();
@@ -471,6 +473,9 @@ public class RawRankProfile implements RankProfilesConfig.Producer {
             if ( ! createPostinglistWhenNonStrict) {
                 properties.add(new Pair<>("vespa.matching.create_postinglist_when_non_strict", String.valueOf(createPostinglistWhenNonStrict)));
             }
+            if (useEstimateForFetchPostings) {
+                properties.add(new Pair<>("vespa.matching.use_estimate_for_fetch_postings", String.valueOf(useEstimateForFetchPostings)));
+            }
             if (postFilterThreshold.isPresent()) {
                 properties.add(new Pair<>("vespa.matching.global_filter.upper_limit", String.valueOf(postFilterThreshold.getAsDouble())));
             }
diff --git a/configserver/src/main/java/com/yahoo/vespa/config/server/deploy/ModelContextImpl.java b/configserver/src/main/java/com/yahoo/vespa/config/server/deploy/ModelContextImpl.java
index 27c24c5d6ed..2f126cd84d3 100644
--- a/configserver/src/main/java/com/yahoo/vespa/config/server/deploy/ModelContextImpl.java
+++ b/configserver/src/main/java/com/yahoo/vespa/config/server/deploy/ModelContextImpl.java
@@ -203,6 +203,7 @@ public class ModelContextImpl implements ModelContext {
         private final String summaryDecodePolicy;
         private final boolean alwaysMarkPhraseExpensive;
         private final boolean createPostinglistWhenNonStrict;
+        private final boolean useEstimateForFetchPostings;
         private final int contentLayerMetadataFeatureLevel;
         private final boolean dynamicHeapSize;
         private final String unknownConfigDefinition;
@@ -254,6 +255,7 @@ public class ModelContextImpl implements ModelContext {
             this.usePerDocumentThrottledDeleteBucket = flagValue(source, appId, version, Flags.USE_PER_DOCUMENT_THROTTLED_DELETE_BUCKET);
             this.alwaysMarkPhraseExpensive =  flagValue(source, appId, version, Flags.ALWAYS_MARK_PHRASE_EXPENSIVE);
             this.createPostinglistWhenNonStrict = flagValue(source, appId, version, Flags.CREATE_POSTINGLIST_WHEN_NON_STRICT);
+            this.useEstimateForFetchPostings = flagValue(source, appId, version, Flags.USE_ESTIMATE_FOR_FETCH_POSTINGS);
         }
 
         @Override public int heapSizePercentage() { return heapPercentage; }
@@ -301,6 +303,7 @@ public class ModelContextImpl implements ModelContext {
         }
         @Override public boolean alwaysMarkPhraseExpensive() { return alwaysMarkPhraseExpensive; }
         @Override public boolean createPostinglistWhenNonStrict() { return createPostinglistWhenNonStrict; }
+        @Override public boolean useEstimateForFetchPostings() { return useEstimateForFetchPostings; }
         @Override public int contentLayerMetadataFeatureLevel() { return contentLayerMetadataFeatureLevel; }
         @Override public boolean dynamicHeapSize() { return dynamicHeapSize; }
         @Override public String unknownConfigDefinition() { return unknownConfigDefinition; }
diff --git a/flags/src/main/java/com/yahoo/vespa/flags/Flags.java b/flags/src/main/java/com/yahoo/vespa/flags/Flags.java
index 5e395f04956..5af7c82a8c4 100644
--- a/flags/src/main/java/com/yahoo/vespa/flags/Flags.java
+++ b/flags/src/main/java/com/yahoo/vespa/flags/Flags.java
@@ -334,6 +334,13 @@ public class Flags {
             "Takes effect at redeployment",
             INSTANCE_ID);
 
+    public static final UnboundBooleanFlag USE_ESTIMATE_FOR_FETCH_POSTINGS = defineFeatureFlag(
+            "use-estimate-for-fetch-postings", false,
+            List.of("baldersheim"), "2023-12-06", "2024-01-31",
+            "If true an estimate assuming uncorrelated query terms is used in Blueprint::fetchPostings",
+            "Takes effect at redeployment",
+            INSTANCE_ID);
+
     public static final UnboundBooleanFlag WRITE_CONFIG_SERVER_SESSION_DATA_AS_ONE_BLOB = defineFeatureFlag(
             "write-config-server-session-data-as-blob", false,
             List.of("hmusum"), "2023-07-19", "2024-02-01",
diff --git a/searchcore/src/vespa/searchcore/proton/matching/attribute_limiter.cpp b/searchcore/src/vespa/searchcore/proton/matching/attribute_limiter.cpp
index 349d33e03e9..d96d202fd4b 100644
--- a/searchcore/src/vespa/searchcore/proton/matching/attribute_limiter.cpp
+++ b/searchcore/src/vespa/searchcore/proton/matching/attribute_limiter.cpp
@@ -99,7 +99,8 @@ AttributeLimiter::create_match_data(size_t want_hits, size_t max_group_size, dou
         FieldSpecList field; // single field API is protected
         field.add(FieldSpec(_attribute_name, my_field_id, my_handle));
         _blueprint = _searchable_attributes.createBlueprint(_requestContext, field, node);
-        auto execInfo = ExecuteInfo::create(strictSearch, strictSearch ? 1.0F : hit_rate, &_requestContext.getDoom(), true);
+        //TODO use_estimate must be switched to true quite soon
+        auto execInfo = ExecuteInfo::create(strictSearch, strictSearch ? 1.0F : hit_rate, &_requestContext.getDoom(), true, false);
         _blueprint->fetchPostings(execInfo);
         _estimatedHits.store(_blueprint->getState().estimate().estHits, std::memory_order_relaxed);
         _blueprint->freeze();
diff --git a/searchcore/src/vespa/searchcore/proton/matching/match_tools.cpp b/searchcore/src/vespa/searchcore/proton/matching/match_tools.cpp
index ad1388f0407..7c8608985c3 100644
--- a/searchcore/src/vespa/searchcore/proton/matching/match_tools.cpp
+++ b/searchcore/src/vespa/searchcore/proton/matching/match_tools.cpp
@@ -17,6 +17,7 @@ using search::queryeval::IDiversifier;
 using search::attribute::diversity::DiversityFilter;
 using search::attribute::BasicType;
 using search::attribute::AttributeBlueprintParams;
+using search::queryeval::ExecuteInfo;
 using vespalib::Issue;
 
 using namespace search::fef::indexproperties::matchphase;
@@ -205,13 +206,15 @@ MatchToolsFactory(QueryLimiter               & queryLimiter,
         trace.addEvent(4, "Perform dictionary lookups and posting lists initialization");
         float hitRate = std::min(1.0F, float(maxNumHits)/float(searchContext.getDocIdLimit()));
         bool create_postinglist_when_non_strict = CreatePostingListWhenNonStrict::check(_queryEnv.getProperties(), rankSetup.create_postinglist_when_non_strict());
-        _query.fetchPostings(search::queryeval::ExecuteInfo::create(is_search, hitRate, &_requestContext.getDoom(),
-                                                                    create_postinglist_when_non_strict));
+        bool use_estimate_for_fetch_postings = UseEstimateForFetchPostings::check(_queryEnv.getProperties(), rankSetup.use_estimate_for_fetch_postings());
+        _query.fetchPostings(ExecuteInfo::create(is_search, hitRate, &_requestContext.getDoom(),
+                                                 create_postinglist_when_non_strict, use_estimate_for_fetch_postings));
         if (is_search) {
             _query.handle_global_filter(_requestContext.getDoom(), searchContext.getDocIdLimit(),
                                         _attribute_blueprint_params.global_filter_lower_limit,
                                         _attribute_blueprint_params.global_filter_upper_limit,
-                                        thread_bundle, trace, create_postinglist_when_non_strict);
+                                        thread_bundle, trace, create_postinglist_when_non_strict,
+                                        use_estimate_for_fetch_postings);
         }
         _query.freeze();
         trace.addEvent(5, "Prepare shared state for multi-threaded rank executors");
diff --git a/searchcore/src/vespa/searchcore/proton/matching/query.cpp b/searchcore/src/vespa/searchcore/proton/matching/query.cpp
index de0a4846615..d9051ac09e7 100644
--- a/searchcore/src/vespa/searchcore/proton/matching/query.cpp
+++ b/searchcore/src/vespa/searchcore/proton/matching/query.cpp
@@ -249,7 +249,7 @@ void
 Query::handle_global_filter(const vespalib::Doom & doom, uint32_t docid_limit,
                             double global_filter_lower_limit, double global_filter_upper_limit,
                             vespalib::ThreadBundle &thread_bundle, search::engine::Trace& trace,
-                            bool create_postinglist_when_non_strict)
+                            bool create_postinglist_when_non_strict, bool use_estimate_for_fetch_postings)
 {
     if (!handle_global_filter(*_blueprint, docid_limit, global_filter_lower_limit, global_filter_upper_limit, thread_bundle, &trace)) {
         return;
@@ -259,7 +259,7 @@ Query::handle_global_filter(const vespalib::Doom & doom, uint32_t docid_limit,
     _blueprint = Blueprint::optimize(std::move(_blueprint));
     LOG(debug, "blueprint after handle_global_filter:\n%s\n", _blueprint->asString().c_str());
     // strictness may change if optimized order changed:
-    fetchPostings(ExecuteInfo::create(true, 1.0F, &doom, create_postinglist_when_non_strict));
+    fetchPostings(ExecuteInfo::create(true, 1.0F, &doom, create_postinglist_when_non_strict, use_estimate_for_fetch_postings));
 }
 
 bool
diff --git a/searchcore/src/vespa/searchcore/proton/matching/query.h b/searchcore/src/vespa/searchcore/proton/matching/query.h
index 3e2c7686066..c3ea2c5e664 100644
--- a/searchcore/src/vespa/searchcore/proton/matching/query.h
+++ b/searchcore/src/vespa/searchcore/proton/matching/query.h
@@ -107,7 +107,7 @@ public:
     void handle_global_filter(const vespalib::Doom & doom, uint32_t docid_limit,
                               double global_filter_lower_limit, double global_filter_upper_limit,
                               vespalib::ThreadBundle &thread_bundle, search::engine::Trace& trace,
-                              bool create_postinglist_when_non_strict);
+                              bool create_postinglist_when_non_strict, bool use_estimate_for_fetch_postings);
 
     /**
      * Calculates and handles the global filter if needed by the blueprint tree.
diff --git a/searchlib/src/vespa/searchlib/fef/indexproperties.cpp b/searchlib/src/vespa/searchlib/fef/indexproperties.cpp
index d503a955afc..637c197b303 100644
--- a/searchlib/src/vespa/searchlib/fef/indexproperties.cpp
+++ b/searchlib/src/vespa/searchlib/fef/indexproperties.cpp
@@ -467,6 +467,12 @@ bool CreatePostingListWhenNonStrict::check(const Properties &props, bool fallbac
     return lookupBool(props, NAME, fallback);
 }
 
+const vespalib::string UseEstimateForFetchPostings::NAME("vespa.matching.use_estimate_for_fetch_postings");
+const bool UseEstimateForFetchPostings::DEFAULT_VALUE(false);
+bool UseEstimateForFetchPostings::check(const Properties &props, bool fallback) {
+    return lookupBool(props, NAME, fallback);
+}
+
 } // namespace matching
 
 namespace softtimeout {
diff --git a/searchlib/src/vespa/searchlib/fef/indexproperties.h b/searchlib/src/vespa/searchlib/fef/indexproperties.h
index 7262e599235..16046709d7e 100644
--- a/searchlib/src/vespa/searchlib/fef/indexproperties.h
+++ b/searchlib/src/vespa/searchlib/fef/indexproperties.h
@@ -357,6 +357,16 @@ namespace matching {
         static bool check(const Properties &props) { return check(props, DEFAULT_VALUE); }
         static bool check(const Properties &props, bool fallback);
     };
+
+    /**
+     * When enabled posting lists can be created on the fly even if iterator is not strict.
+     **/
+    struct UseEstimateForFetchPostings {
+        static const vespalib::string NAME;
+        static const bool DEFAULT_VALUE;
+        static bool check(const Properties &props) { return check(props, DEFAULT_VALUE); }
+        static bool check(const Properties &props, bool fallback);
+    };
 }
 
 namespace softtimeout {
diff --git a/searchlib/src/vespa/searchlib/fef/ranksetup.cpp b/searchlib/src/vespa/searchlib/fef/ranksetup.cpp
index ed74386b2fa..1f30a3b59e9 100644
--- a/searchlib/src/vespa/searchlib/fef/ranksetup.cpp
+++ b/searchlib/src/vespa/searchlib/fef/ranksetup.cpp
@@ -62,6 +62,7 @@ RankSetup::RankSetup(const BlueprintFactory &factory, const IIndexEnvironment &i
       _degradationAscendingOrder(false),
       _always_mark_phrase_expensive(false),
       _create_postinglist_when_non_strict(true),
+      _use_estimate_for_fetch_postings(false),
       _diversityAttribute(),
       _diversityMinGroups(1),
       _diversityCutoffFactor(10.0),
@@ -137,6 +138,7 @@ RankSetup::configure()
     _mutateAllowQueryOverride = mutate::AllowQueryOverride::check(_indexEnv.getProperties());
     _always_mark_phrase_expensive = matching::AlwaysMarkPhraseExpensive::check(_indexEnv.getProperties());
     _create_postinglist_when_non_strict = matching::CreatePostingListWhenNonStrict::check(_indexEnv.getProperties());
+    _use_estimate_for_fetch_postings = matching::UseEstimateForFetchPostings::check(_indexEnv.getProperties());
 }
 
 void
diff --git a/searchlib/src/vespa/searchlib/fef/ranksetup.h b/searchlib/src/vespa/searchlib/fef/ranksetup.h
index d560614ce39..8e4a6c4246e 100644
--- a/searchlib/src/vespa/searchlib/fef/ranksetup.h
+++ b/searchlib/src/vespa/searchlib/fef/ranksetup.h
@@ -71,6 +71,7 @@ private:
     bool                     _degradationAscendingOrder;
     bool                     _always_mark_phrase_expensive;
     bool                     _create_postinglist_when_non_strict;
+    bool                     _use_estimate_for_fetch_postings;
     vespalib::string         _diversityAttribute;
     uint32_t                 _diversityMinGroups;
     double                   _diversityCutoffFactor;
@@ -224,6 +225,7 @@ public:
     }
     bool always_mark_phrase_expensive() const noexcept { return _always_mark_phrase_expensive; }
     bool create_postinglist_when_non_strict() const noexcept { return _create_postinglist_when_non_strict; }
+    bool use_estimate_for_fetch_postings() const noexcept { return _use_estimate_for_fetch_postings; }
     /** get number of hits to collect during graceful degradation in match phase */
     uint32_t getDegradationMaxHits() const {
         return _degradationMaxHits;
diff --git a/searchlib/src/vespa/searchlib/queryeval/blueprint.cpp b/searchlib/src/vespa/searchlib/queryeval/blueprint.cpp
index 6bc125226de..1088decb8d6 100644
--- a/searchlib/src/vespa/searchlib/queryeval/blueprint.cpp
+++ b/searchlib/src/vespa/searchlib/queryeval/blueprint.cpp
@@ -519,10 +519,11 @@ IntermediateBlueprint::calculateState() const
 }
 
 double
-IntermediateBlueprint::computeNextHitRate(const Blueprint & child, double hitRate) const
+IntermediateBlueprint::computeNextHitRate(const Blueprint & child, double hit_rate, bool use_estimate) const
 {
     (void) child;
-    return hitRate;
+    (void) use_estimate;
+    return hit_rate;
 }
 
 bool
@@ -625,7 +626,7 @@ IntermediateBlueprint::fetchPostings(const ExecuteInfo &execInfo)
     for (size_t i = 0; i < _children.size(); ++i) {
         Blueprint & child = *_children[i];
         child.fetchPostings(ExecuteInfo::create(execInfo.isStrict() && inheritStrict(i), nextHitRate, execInfo));
-        nextHitRate = computeNextHitRate(child, nextHitRate);
+        nextHitRate = computeNextHitRate(child, nextHitRate, execInfo.use_estimate_for_fetch_postings());
     }
 }
 
diff --git a/searchlib/src/vespa/searchlib/queryeval/blueprint.h b/searchlib/src/vespa/searchlib/queryeval/blueprint.h
index a02cb7dd17f..a61d435ac25 100644
--- a/searchlib/src/vespa/searchlib/queryeval/blueprint.h
+++ b/searchlib/src/vespa/searchlib/queryeval/blueprint.h
@@ -113,7 +113,9 @@ public:
             _estimateHits = est.estHits;
             _estimateEmpty = est.empty;
         }
+        //TODO replace use of estimate by using empty/estHits directly and then have a real estimate here
         HitEstimate estimate() const noexcept { return {_estimateHits, _estimateEmpty}; }
+
         double hit_ratio(uint32_t docid_limit) const noexcept {
             uint32_t total_hits = _estimateHits;
             uint32_t total_docs = std::max(total_hits, docid_limit);
@@ -237,6 +239,8 @@ public:
     const Blueprint &root() const;
 
     double hit_ratio() const noexcept { return getState().hit_ratio(_docid_limit); }
+    // TODO Call getState().estimate() when it return a normalized estimate
+    double estimate() const noexcept { return getState().hit_ratio(_docid_limit); }
 
     virtual void fetchPostings(const ExecuteInfo &execInfo) = 0;
     virtual void freeze() = 0;
@@ -318,7 +322,7 @@ private:
     bool infer_want_global_filter() const;
 
     size_t count_termwise_nodes(const UnpackInfo &unpack) const;
-    virtual double computeNextHitRate(const Blueprint & child, double hitRate) const;
+    virtual double computeNextHitRate(const Blueprint & child, double hit_rate, bool use_estimate) const;
 
 protected:
     // returns an empty collection if children have empty or
diff --git a/searchlib/src/vespa/searchlib/queryeval/executeinfo.cpp b/searchlib/src/vespa/searchlib/queryeval/executeinfo.cpp
index 27366a9b924..ac3dfcc3b20 100644
--- a/searchlib/src/vespa/searchlib/queryeval/executeinfo.cpp
+++ b/searchlib/src/vespa/searchlib/queryeval/executeinfo.cpp
@@ -4,7 +4,7 @@
 
 namespace search::queryeval {
 
-const ExecuteInfo ExecuteInfo::TRUE(true, 1.0, nullptr, true);
-const ExecuteInfo ExecuteInfo::FALSE(false, 1.0, nullptr, true);
+const ExecuteInfo ExecuteInfo::TRUE(true, 1.0, nullptr, true, true);
+const ExecuteInfo ExecuteInfo::FALSE(false, 1.0, nullptr, true, true);
 
 }
diff --git a/searchlib/src/vespa/searchlib/queryeval/executeinfo.h b/searchlib/src/vespa/searchlib/queryeval/executeinfo.h
index 0095429e609..1d6cf7281ea 100644
--- a/searchlib/src/vespa/searchlib/queryeval/executeinfo.h
+++ b/searchlib/src/vespa/searchlib/queryeval/executeinfo.h
@@ -12,43 +12,50 @@ namespace search::queryeval {
  */
 class ExecuteInfo {
 public:
-    ExecuteInfo() noexcept : ExecuteInfo(false, 1.0F, nullptr, true) { }
+    ExecuteInfo() noexcept : ExecuteInfo(false, 1.0F, nullptr, true, true) { }
     bool isStrict() const noexcept { return _strict; }
     bool create_postinglist_when_non_strict() const noexcept { return _create_postinglist_when_non_strict; }
+    bool use_estimate_for_fetch_postings() const noexcept { return _use_estimate_for_fetch_postings; }
     float hitRate() const noexcept { return _hitRate; }
     bool soft_doom() const noexcept { return _doom && _doom->soft_doom(); }
     const vespalib::Doom * getDoom() const { return _doom; }
     static const ExecuteInfo TRUE;
     static const ExecuteInfo FALSE;
     static ExecuteInfo create(bool strict, const ExecuteInfo & org) noexcept {
-        return {strict, org._hitRate, org.getDoom(), org.create_postinglist_when_non_strict()};
+        return create(strict, org._hitRate, org);
     }
     static ExecuteInfo create(bool strict, float hitRate, const ExecuteInfo & org) noexcept {
-        return {strict, hitRate, org.getDoom(), org.create_postinglist_when_non_strict()};
+        return {strict, hitRate, org.getDoom(), org.create_postinglist_when_non_strict(), org.use_estimate_for_fetch_postings()};
     }
-    static ExecuteInfo create(bool strict, float hitRate, const vespalib::Doom * doom) noexcept {
-        return create(strict, hitRate, doom, true);
-    }
-    static ExecuteInfo create(bool strict, float hitRate, const vespalib::Doom * doom, bool postinglist_when_non_strict) noexcept {
-        return {strict, hitRate, doom, postinglist_when_non_strict};
+
+    static ExecuteInfo create(bool strict, float hitRate, const vespalib::Doom * doom, bool postinglist_when_non_strict,
+                              bool use_estimate_for_fetch_postings) noexcept
+    {
+         return {strict, hitRate, doom, postinglist_when_non_strict, use_estimate_for_fetch_postings};
     }
     static ExecuteInfo createForTest(bool strict) noexcept {
         return createForTest(strict, 1.0F);
     }
     static ExecuteInfo createForTest(bool strict, float hitRate) noexcept {
-        return create(strict, hitRate, nullptr);
+        return createForTest(strict, hitRate, nullptr);
+    }
+    static ExecuteInfo createForTest(bool strict, float hitRate, const vespalib::Doom * doom) noexcept {
+        return create(strict, hitRate, doom, true, true);
     }
 private:
-    ExecuteInfo(bool strict, float hitRate_in, const vespalib::Doom * doom, bool postinglist_when_non_strict) noexcept
+    ExecuteInfo(bool strict, float hitRate_in, const vespalib::Doom * doom, bool postinglist_when_non_strict,
+                bool use_estimate_for_fetch_postings) noexcept
         : _doom(doom),
           _hitRate(hitRate_in),
           _strict(strict),
-          _create_postinglist_when_non_strict(postinglist_when_non_strict)
+          _create_postinglist_when_non_strict(postinglist_when_non_strict),
+          _use_estimate_for_fetch_postings(use_estimate_for_fetch_postings)
     { }
     const vespalib::Doom * _doom;
     float                  _hitRate;
     bool                   _strict;
     bool                   _create_postinglist_when_non_strict;
+    bool                   _use_estimate_for_fetch_postings;
 };
 
 }
diff --git a/searchlib/src/vespa/searchlib/queryeval/intermediate_blueprints.cpp b/searchlib/src/vespa/searchlib/queryeval/intermediate_blueprints.cpp
index 4d0656b421c..c4044ba3d00 100644
--- a/searchlib/src/vespa/searchlib/queryeval/intermediate_blueprints.cpp
+++ b/searchlib/src/vespa/searchlib/queryeval/intermediate_blueprints.cpp
@@ -270,19 +270,21 @@ AndBlueprint::createFilterSearch(bool strict, FilterConstraint constraint) const
 }
 
 double
-AndBlueprint::computeNextHitRate(const Blueprint & child, double hitRate) const {
-    return hitRate * child.hit_ratio();
+AndBlueprint::computeNextHitRate(const Blueprint & child, double hit_rate, bool use_estimate) const {
+    double estimate = use_estimate ? child.estimate() : child.hit_ratio();
+    return hit_rate * estimate;
 }
 
 double
-OrBlueprint::computeNextHitRate(const Blueprint & child, double hitRate) const {
+OrBlueprint::computeNextHitRate(const Blueprint & child, double hit_rate, bool use_estimate) const {
     // Avoid dropping hitRate to zero when meeting a conservatively high hitrate in a child.
     // Happens at least when using non fast-search attributes, and with AND nodes.
     constexpr double MIN_INVERSE_HIT_RATIO = 0.10;
-    double inverse_child_hit_ratio = 1.0 - child.hit_ratio();
-    return (inverse_child_hit_ratio > MIN_INVERSE_HIT_RATIO)
-        ? hitRate * inverse_child_hit_ratio
-        : hitRate;
+    double estimate = use_estimate ? child.estimate() : child.hit_ratio();
+    double inverse_child_estimate = 1.0 - estimate;
+    return (inverse_child_estimate > MIN_INVERSE_HIT_RATIO)
+        ? hit_rate * inverse_child_estimate
+        : hit_rate;
 }
 
 //-----------------------------------------------------------------------------
diff --git a/searchlib/src/vespa/searchlib/queryeval/intermediate_blueprints.h b/searchlib/src/vespa/searchlib/queryeval/intermediate_blueprints.h
index 6d8082b60f6..1d88b3b21eb 100644
--- a/searchlib/src/vespa/searchlib/queryeval/intermediate_blueprints.h
+++ b/searchlib/src/vespa/searchlib/queryeval/intermediate_blueprints.h
@@ -54,7 +54,7 @@ public:
     SearchIterator::UP
     createFilterSearch(bool strict, FilterConstraint constraint) const override;
 private:
-    double computeNextHitRate(const Blueprint & child, double hitRate) const override;
+    double computeNextHitRate(const Blueprint & child, double hit_rate, bool use_estimate) const override;
 };
 
 //-----------------------------------------------------------------------------
@@ -78,7 +78,7 @@ public:
     SearchIterator::UP
     createFilterSearch(bool strict, FilterConstraint constraint) const override;
 private:
-    double computeNextHitRate(const Blueprint & child, double hitRate) const override;
+    double computeNextHitRate(const Blueprint & child, double hit_rate, bool use_estimate) const override;
     uint8_t calculate_cost_tier() const override;
 };
 
diff --git a/searchlib/src/vespa/searchlib/queryeval/same_element_blueprint.cpp b/searchlib/src/vespa/searchlib/queryeval/same_element_blueprint.cpp
index c93cef47c27..eb1d217ad6a 100644
--- a/searchlib/src/vespa/searchlib/queryeval/same_element_blueprint.cpp
+++ b/searchlib/src/vespa/searchlib/queryeval/same_element_blueprint.cpp
@@ -28,7 +28,7 @@ SameElementBlueprint::~SameElementBlueprint() = default;
 FieldSpec
 SameElementBlueprint::getNextChildField(const vespalib::string &field_name, uint32_t field_id)
 {
-    return FieldSpec(field_name, field_id, _layout.allocTermField(field_id), false);
+    return {field_name, field_id, _layout.allocTermField(field_id), false};
 }
 
 void
@@ -60,11 +60,13 @@ SameElementBlueprint::fetchPostings(const ExecuteInfo &execInfo)
 {
     if (_terms.empty()) return;
     _terms[0]->fetchPostings(execInfo);
-    double hit_rate = execInfo.hitRate() * _terms[0]->hit_ratio();
+    double estimate = execInfo.use_estimate_for_fetch_postings() ? _terms[0]->hit_ratio() : _terms[0]->estimate();
+    double hit_rate = execInfo.hitRate() * estimate;
     for (size_t i = 1; i < _terms.size(); ++i) {
         Blueprint & term = *_terms[i];
         term.fetchPostings(ExecuteInfo::create(false, hit_rate, execInfo));
-        hit_rate = hit_rate * term.hit_ratio();
+        estimate = execInfo.use_estimate_for_fetch_postings() ? _terms[0]->hit_ratio() : _terms[0]->estimate();
+        hit_rate = hit_rate * estimate;
     }
 }