Merge pull request #4949 from vespa-engine/balder/cleanup-softtimeout

Balder/cleanup softtimeout

12 files changed, 90 insertions, 71 deletions

diff --git a/searchcore/src/tests/proton/matching/matching_stats_test.cpp b/searchcore/src/tests/proton/matching/matching_stats_test.cpp
index 46cba2d59c4..b94026e689c 100644
--- a/searchcore/src/tests/proton/matching/matching_stats_test.cpp
+++ b/searchcore/src/tests/proton/matching/matching_stats_test.cpp
@@ -1,13 +1,16 @@
 // Copyright 2017 Yahoo Holdings. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
-#include <vespa/log/log.h>
-LOG_SETUP("matching_stats_test");
+
 #include <vespa/vespalib/testkit/test_kit.h>
 #include <vespa/searchcore/proton/matching/matching_stats.h>
 
+#include <vespa/log/log.h>
+LOG_SETUP("matching_stats_test");
+
 using namespace proton::matching;
 
 TEST("requireThatDocCountsAddUp") {
     MatchingStats stats;
+    EXPECT_EQUAL(0u, stats.docsCovered());
     EXPECT_EQUAL(0u, stats.docsMatched());
     EXPECT_EQUAL(0u, stats.docsRanked());
     EXPECT_EQUAL(0u, stats.docsReRanked());
@@ -15,6 +18,7 @@ TEST("requireThatDocCountsAddUp") {
     EXPECT_EQUAL(0u, stats.limited_queries());
     {
         MatchingStats rhs;
+        EXPECT_EQUAL(&rhs.docsCovered(10000), &rhs);
         EXPECT_EQUAL(&rhs.docsMatched(1000), &rhs);
         EXPECT_EQUAL(&rhs.docsRanked(100), &rhs);
         EXPECT_EQUAL(&rhs.docsReRanked(10), &rhs);
@@ -22,13 +26,15 @@ TEST("requireThatDocCountsAddUp") {
         EXPECT_EQUAL(&rhs.limited_queries(1), &rhs);
         EXPECT_EQUAL(&stats.add(rhs), &stats);
     }
+    EXPECT_EQUAL(10000u, stats.docsCovered());
     EXPECT_EQUAL(1000u, stats.docsMatched());
     EXPECT_EQUAL(100u, stats.docsRanked());
     EXPECT_EQUAL(10u, stats.docsReRanked());
     EXPECT_EQUAL(2u, stats.queries());
     EXPECT_EQUAL(1u, stats.limited_queries());
-    EXPECT_EQUAL(&stats.add(MatchingStats().docsMatched(1000).docsRanked(100)
+    EXPECT_EQUAL(&stats.add(MatchingStats().docsCovered(10000).docsMatched(1000).docsRanked(100)
                             .docsReRanked(10).queries(2).limited_queries(1)), &stats);
+    EXPECT_EQUAL(20000u, stats.docsCovered());
     EXPECT_EQUAL(2000u, stats.docsMatched());
     EXPECT_EQUAL(200u, stats.docsRanked());
     EXPECT_EQUAL(20u, stats.docsReRanked());
@@ -84,12 +90,14 @@ TEST("requireThatAverageTimesAreRecorded") {
 
 TEST("requireThatPartitionsAreAddedCorrectly") {
     MatchingStats all1;
+    EXPECT_EQUAL(0u, all1.docsCovered());
     EXPECT_EQUAL(0u, all1.docsMatched());
     EXPECT_EQUAL(0u, all1.getNumPartitions());
 
     MatchingStats::Partition subPart;
-    subPart.docsMatched(3).docsRanked(2).docsReRanked(1)
+    subPart.docsCovered(7).docsMatched(3).docsRanked(2).docsReRanked(1)
         .active_time(1.0).wait_time(0.5);
+    EXPECT_EQUAL(7u, subPart.docsCovered());
     EXPECT_EQUAL(3u, subPart.docsMatched());
     EXPECT_EQUAL(2u, subPart.docsRanked());
     EXPECT_EQUAL(1u, subPart.docsReRanked());
@@ -99,10 +107,12 @@ TEST("requireThatPartitionsAreAddedCorrectly") {
     EXPECT_EQUAL(1u, subPart.wait_time_count());
 
     all1.merge_partition(subPart, 0);
+    EXPECT_EQUAL(7u, all1.docsCovered());
     EXPECT_EQUAL(3u, all1.docsMatched());
     EXPECT_EQUAL(2u, all1.docsRanked());
     EXPECT_EQUAL(1u, all1.docsReRanked());
     EXPECT_EQUAL(1u, all1.getNumPartitions());
+    EXPECT_EQUAL(7u, all1.getPartition(0).docsCovered());
     EXPECT_EQUAL(3u, all1.getPartition(0).docsMatched());
     EXPECT_EQUAL(2u, all1.getPartition(0).docsRanked());
     EXPECT_EQUAL(1u, all1.getPartition(0).docsReRanked());
@@ -112,6 +122,7 @@ TEST("requireThatPartitionsAreAddedCorrectly") {
     EXPECT_EQUAL(1u, all1.getPartition(0).wait_time_count());
     
     all1.merge_partition(subPart, 1);
+    EXPECT_EQUAL(14u, all1.docsCovered());
     EXPECT_EQUAL(6u, all1.docsMatched());
     EXPECT_EQUAL(4u, all1.docsRanked());
     EXPECT_EQUAL(2u, all1.docsReRanked());
@@ -125,6 +136,7 @@ TEST("requireThatPartitionsAreAddedCorrectly") {
     EXPECT_EQUAL(1u, all1.getPartition(1).wait_time_count());
 
     all1.add(all1);
+    EXPECT_EQUAL(28u, all1.docsCovered());
     EXPECT_EQUAL(12u, all1.docsMatched());
     EXPECT_EQUAL(8u, all1.docsRanked());
     EXPECT_EQUAL(4u, all1.docsReRanked());
diff --git a/searchcore/src/vespa/searchcore/fdispatch/common/search.h b/searchcore/src/vespa/searchcore/fdispatch/common/search.h
index 8ca63838c5f..a1a8eb9f0ba 100644
--- a/searchcore/src/vespa/searchcore/fdispatch/common/search.h
+++ b/searchcore/src/vespa/searchcore/fdispatch/common/search.h
@@ -100,6 +100,8 @@ public:
     uint64_t  _activeDocs;
     uint64_t  _soonActiveDocs;
     uint32_t  _degradeReason;
+    uint16_t  _nodesQueried;
+    uint16_t  _nodesReplied;
 
     FastS_SearchInfo()
         : _searchOffset(0),
@@ -107,9 +109,10 @@ public:
           _coverageDocs(0),
           _activeDocs(0),
           _soonActiveDocs(0),
-          _degradeReason(0)
-    {
-    }
+          _degradeReason(0),
+          _nodesQueried(0),
+          _nodesReplied(0)
+    { }
 };
 
 //----------------------------------------------------------------
diff --git a/searchcore/src/vespa/searchcore/fdispatch/program/searchadapter.cpp b/searchcore/src/vespa/searchcore/fdispatch/program/searchadapter.cpp
index dd4109da5cf..824688a75f6 100644
--- a/searchcore/src/vespa/searchcore/fdispatch/program/searchadapter.cpp
+++ b/searchcore/src/vespa/searchcore/fdispatch/program/searchadapter.cpp
@@ -56,6 +56,8 @@ SearchAdapter::createReply()
     r.coverage = SearchReply::Coverage(_searchInfo->_activeDocs, _searchInfo->_coverageDocs);
     r.coverage.setSoonActive(_searchInfo->_soonActiveDocs);
     r.coverage.setDegradeReason(_searchInfo->_degradeReason);
+    r.coverage.setNodesQueried(_searchInfo->_nodesQueried);
+    r.coverage.setNodesReplied(_searchInfo->_nodesReplied);
 
     FastS_hitresult *hitbuf = _queryResult->_hitbuf;
     r.hits.resize(hitcnt);
diff --git a/searchcore/src/vespa/searchcore/fdispatch/program/searchadapter.h b/searchcore/src/vespa/searchcore/fdispatch/program/searchadapter.h
index d60b39c52be..de941505fc6 100644
--- a/searchcore/src/vespa/searchcore/fdispatch/program/searchadapter.h
+++ b/searchcore/src/vespa/searchcore/fdispatch/program/searchadapter.h
@@ -35,7 +35,7 @@ private:
     void writeLog();
     void cleanup();
 
-    virtual void Run(FastOS_ThreadInterface *, void *) override;
+    void Run(FastOS_ThreadInterface *, void *) override;
 
 public:
     SearchAdapter(FastS_AppContext *appCtx,
diff --git a/searchcore/src/vespa/searchcore/fdispatch/search/fnet_search.cpp b/searchcore/src/vespa/searchcore/fdispatch/search/fnet_search.cpp
index 85599b9e897..98642c6edf6 100644
--- a/searchcore/src/vespa/searchcore/fdispatch/search/fnet_search.cpp
+++ b/searchcore/src/vespa/searchcore/fdispatch/search/fnet_search.cpp
@@ -884,7 +884,7 @@ FastS_FNET_Search::CheckCoverage()
     if ((cntNone > 0) && (cntNone != _nodes.size())) {
         activeDocs += cntNone * activeDocs/(_nodes.size() - cntNone);
     }
-    _util.SetCoverage(covDocs, activeDocs, soonActiveDocs, degradedReason);
+    _util.SetCoverage(covDocs, activeDocs, soonActiveDocs, degradedReason, _nodes.size(), _nodes.size() - cntNone);
 }
 
 
diff --git a/searchcore/src/vespa/searchcore/fdispatch/search/querycacheutil.h b/searchcore/src/vespa/searchcore/fdispatch/search/querycacheutil.h
index 6fdca46530c..442fa3f0710 100644
--- a/searchcore/src/vespa/searchcore/fdispatch/search/querycacheutil.h
+++ b/searchcore/src/vespa/searchcore/fdispatch/search/querycacheutil.h
@@ -80,12 +80,15 @@ public:
             ret = 0.0;
         return ret;
     }
-    void SetCoverage(uint64_t coverageDocs, uint64_t activeDocs, uint64_t soonActiveDocs, uint32_t degradeReason)
+    void SetCoverage(uint64_t coverageDocs, uint64_t activeDocs, uint64_t soonActiveDocs,
+                     uint32_t degradeReason, uint16_t nodesQueried, uint16_t nodesReplied)
     {
         _searchInfo._coverageDocs  = coverageDocs;
         _searchInfo._activeDocs  = activeDocs;
         _searchInfo._soonActiveDocs = soonActiveDocs;
         _searchInfo._degradeReason = degradeReason;
+        _searchInfo._nodesQueried = nodesQueried;
+        _searchInfo._nodesReplied = nodesReplied;
     }
     void SetAlignedHitCount(uint32_t alignedHitCount) {
         if (alignedHitCount > _alignedMaxHits) {
diff --git a/searchcore/src/vespa/searchcore/proton/matching/docid_range_scheduler.h b/searchcore/src/vespa/searchcore/proton/matching/docid_range_scheduler.h
index 67e52cbe8ee..e6fce89e82d 100644
--- a/searchcore/src/vespa/searchcore/proton/matching/docid_range_scheduler.h
+++ b/searchcore/src/vespa/searchcore/proton/matching/docid_range_scheduler.h
@@ -10,8 +10,7 @@
 #include <algorithm>
 #include <vector>
 
-namespace proton {
-namespace matching {
+namespace proton::matching {
 
 /**
  * A range of document ids representing a subset of the search space.
@@ -205,5 +204,4 @@ public:
     DocidRange share_range(size_t, DocidRange todo) override;
 };
 
-} // namespace proton::matching
-} // namespace proton
+}
diff --git a/searchcore/src/vespa/searchcore/proton/matching/match_thread.cpp b/searchcore/src/vespa/searchcore/proton/matching/match_thread.cpp
index bd6a06ac4f1..c1c4387cf41 100644
--- a/searchcore/src/vespa/searchcore/proton/matching/match_thread.cpp
+++ b/searchcore/src/vespa/searchcore/proton/matching/match_thread.cpp
@@ -140,7 +140,7 @@ MatchThread::try_share(DocidRange &docid_range, uint32_t next_docid) {
 }
 
 template <typename Strategy, bool do_rank, bool do_limit, bool do_share_work>
-bool
+uint32_t
 MatchThread::inner_match_loop(Context &context, MatchTools &tools, DocidRange docid_range)
 {
     SearchIterator *search = &tools.search();
@@ -164,7 +164,7 @@ MatchThread::inner_match_loop(Context &context, MatchTools &tools, DocidRange do
             docId = Strategy::seek_next(*search, docId + 1);
         }
     }
-    return (docId < docid_range.end);
+    return docId;
 }
 
 template <typename Strategy, bool do_rank, bool do_limit, bool do_share_work>
@@ -172,12 +172,15 @@ void
 MatchThread::match_loop(MatchTools &tools, HitCollector &hits)
 {
     bool softDoomed = false;
+    uint32_t docsCovered = 0;
     Context context(matchParams.rankDropLimit, tools, hits, num_threads);
     for (DocidRange docid_range = scheduler.first_range(thread_id);
          !docid_range.empty() && ! softDoomed;
          docid_range = scheduler.next_range(thread_id))
     {
-        softDoomed = inner_match_loop<Strategy, do_rank, do_limit, do_share_work>(context, tools, docid_range);
+        uint32_t lastCovered = inner_match_loop<Strategy, do_rank, do_limit, do_share_work>(context, tools, docid_range);
+        softDoomed = (lastCovered < docid_range.end);
+        docsCovered += std::min(lastCovered, docid_range.end) - docid_range.begin;
     }
     uint32_t matches = context.matches;
     if (do_limit && context.isBelowLimit()) {
@@ -187,6 +190,7 @@ MatchThread::match_loop(MatchTools &tools, HitCollector &hits)
         estimate_match_frequency(matches, searchedSoFar);
         tools.match_limiter().updateDocIdSpaceEstimate(searchedSoFar, 0);
     }
+    thread_stats.docsCovered(docsCovered);
     thread_stats.docsMatched(matches);
     thread_stats.softDoomed(softDoomed);
     if (do_rank) {
diff --git a/searchcore/src/vespa/searchcore/proton/matching/match_thread.h b/searchcore/src/vespa/searchcore/proton/matching/match_thread.h
index b08323fa099..b7ecf149001 100644
--- a/searchcore/src/vespa/searchcore/proton/matching/match_thread.h
+++ b/searchcore/src/vespa/searchcore/proton/matching/match_thread.h
@@ -75,7 +75,7 @@ private:
     bool try_share(DocidRange &docid_range, uint32_t next_docid) __attribute__((noinline));
 
     template <typename Strategy, bool do_rank, bool do_limit, bool do_share_work>
-    bool inner_match_loop(Context &context, MatchTools &tools, DocidRange docid_range) __attribute__((noinline));
+    uint32_t inner_match_loop(Context &context, MatchTools &tools, DocidRange docid_range) __attribute__((noinline));
 
     template <typename Strategy, bool do_rank, bool do_limit, bool do_share_work>
     void match_loop(MatchTools &tools, HitCollector &hits) __attribute__((noinline));
diff --git a/searchcore/src/vespa/searchcore/proton/matching/matcher.cpp b/searchcore/src/vespa/searchcore/proton/matching/matcher.cpp
index bbe6f604e4e..f21293299c7 100644
--- a/searchcore/src/vespa/searchcore/proton/matching/matcher.cpp
+++ b/searchcore/src/vespa/searchcore/proton/matching/matcher.cpp
@@ -14,7 +14,6 @@
 #include <vespa/searchlib/engine/searchreply.h>
 #include <vespa/searchlib/features/setup.h>
 #include <vespa/searchlib/fef/test/plugin/setup.h>
-#include <cmath>
 
 #include <vespa/log/log.h>
 LOG_SETUP(".proton.matching.matcher");
@@ -92,11 +91,8 @@ bool willNotNeedRanking(const SearchRequest & request, const GroupingContext & g
 }  // namespace proton::matching::<unnamed>
 
 FeatureSet::SP
-Matcher::getFeatureSet(const DocsumRequest & req,
-                       ISearchContext & searchCtx,
-                       IAttributeContext & attrCtx,
-                       SessionManager & sessionMgr,
-                       bool summaryFeatures)
+Matcher::getFeatureSet(const DocsumRequest & req, ISearchContext & searchCtx, IAttributeContext & attrCtx,
+                       SessionManager & sessionMgr, bool summaryFeatures)
 {
     SessionId sessionId(&req.sessionId[0], req.sessionId.size());
     if (!sessionId.empty()) {
@@ -114,22 +110,18 @@ Matcher::getFeatureSet(const DocsumRequest & req,
     }
 
     StupidMetaStore metaStore;
-    MatchToolsFactory::UP mtf = create_match_tools_factory(req, searchCtx, attrCtx, metaStore, req.propertiesMap.featureOverrides());
+    MatchToolsFactory::UP mtf = create_match_tools_factory(req, searchCtx, attrCtx, metaStore,
+                                                           req.propertiesMap.featureOverrides());
     if (!mtf->valid()) {
-        LOG(warning, "getFeatureSet(%s): query execution failed "
-            "(invalid query). Returning empty feature set",
-            (summaryFeatures ? "summary features" : "rank features"));
+        LOG(warning, "getFeatureSet(%s): query execution failed (invalid query). Returning empty feature set",
+                     (summaryFeatures ? "summary features" : "rank features"));
         return FeatureSet::SP(new FeatureSet());
     }
     return findFeatureSet(req, *mtf, summaryFeatures);
 }
 
-Matcher::Matcher(const search::index::Schema &schema,
-                 const Properties &props,
-                 const vespalib::Clock &clock,
-                 QueryLimiter &queryLimiter,
-                 const IConstantValueRepo &constantValueRepo,
-                 uint32_t distributionKey)
+Matcher::Matcher(const search::index::Schema &schema, const Properties &props, const vespalib::Clock &clock,
+                 QueryLimiter &queryLimiter, const IConstantValueRepo &constantValueRepo, uint32_t distributionKey)
     : _indexEnv(schema, props, constantValueRepo),
       _blueprintFactory(),
       _rankSetup(),
@@ -163,21 +155,21 @@ using search::fef::indexproperties::softtimeout::Enabled;
 using search::fef::indexproperties::softtimeout::Factor;
 
 std::unique_ptr<MatchToolsFactory>
-Matcher::create_match_tools_factory(const search::engine::Request &request,
-                                    ISearchContext &searchContext,
-                                    IAttributeContext &attrContext,
-                                    const search::IDocumentMetaStore &metaStore,
+Matcher::create_match_tools_factory(const search::engine::Request &request, ISearchContext &searchContext,
+                                    IAttributeContext &attrContext, const search::IDocumentMetaStore &metaStore,
                                     const Properties &feature_overrides) const
 {
     const Properties & rankProperties = request.propertiesMap.rankProperties();
     bool softTimeoutEnabled = Enabled::lookup(rankProperties, _rankSetup->getSoftTimeoutEnabled());
-    double factor = 0.95;
+    double factor = softTimeoutEnabled
+                    ? Factor::lookup(rankProperties, _stats.softDoomFactor())
+                    : 0.95;
+    int64_t safeLeft = request.getTimeLeft() * factor;
+    fastos::TimeStamp safeDoom(fastos::ClockSystem::now() + safeLeft);
     if (softTimeoutEnabled) {
-        factor = Factor::lookup(rankProperties, _stats.softDoomFactor());
-        LOG(debug, "Enabling soft-timeout computed factor=%1.3f, used factor=%1.3f", _stats.softDoomFactor(), factor);
+        LOG(debug, "Soft-timeout computed factor=%1.3f, used factor=%1.3f, softTimeout=%lu softDoom=%ld hardDoom=%ld",
+                   _stats.softDoomFactor(), factor, safeLeft, safeDoom.ns(), request.getTimeOfDoom().ns());
     }
-    uint64_t safeLeft = request.getTimeLeft() * factor;
-    fastos::TimeStamp safeDoom(fastos::ClockSystem::now() + safeLeft);
     return std::make_unique<MatchToolsFactory>(_queryLimiter, vespalib::Doom(_clock, safeDoom),
                                                vespalib::Doom(_clock, request.getTimeOfDoom()), searchContext,
                                                attrContext, request.getStackRef(), request.location, _viewResolver,
@@ -185,8 +177,7 @@ Matcher::create_match_tools_factory(const search::engine::Request &request,
 }
 
 SearchReply::UP
-Matcher::handleGroupingSession(SessionManager &sessionMgr,
-                               GroupingContext & groupingContext,
+Matcher::handleGroupingSession(SessionManager &sessionMgr, GroupingContext & groupingContext,
                                GroupingSession::UP groupingSession)
 {
     SearchReply::UP reply = std::make_unique<SearchReply>();
@@ -209,12 +200,9 @@ Matcher::computeNumThreadsPerSearch(Blueprint::HitEstimate hits, const Propertie
 }
 
 SearchReply::UP
-Matcher::match(const SearchRequest &request,
-               vespalib::ThreadBundle &threadBundle,
-               ISearchContext &searchContext,
-               IAttributeContext &attrContext,
-               SessionManager &sessionMgr,
-               const search::IDocumentMetaStore &metaStore,
+Matcher::match(const SearchRequest &request, vespalib::ThreadBundle &threadBundle,
+               ISearchContext &searchContext, IAttributeContext &attrContext,
+               SessionManager &sessionMgr, const search::IDocumentMetaStore &metaStore,
                SearchSession::OwnershipBundle &&owned_objects)
 {
     fastos::StopWatch total_matching_time;
@@ -279,15 +267,7 @@ Matcher::match(const SearchRequest &request,
             sessionMgr.insert(std::move(session));
         }
         reply = std::move(result->_reply);
-        SearchReply::Coverage & coverage = reply->coverage;
-        if (wasLimited) {
-            LOG(debug, "was limited, degraded from match phase");
-            coverage.degradeMatchPhase();
-        }
-        if (my_stats.softDoomed()) {
-            LOG(debug, "soft doomed, degraded from timeout");
-            coverage.degradeTimeout();
-        }
+
         uint32_t numActiveLids = metaStore.getNumActiveLids();
         // note: this is actually totalSpace+1, since 0 is reserved
         uint32_t totalSpace = metaStore.getCommittedDocIdLimit();
@@ -303,10 +283,20 @@ Matcher::match(const SearchRequest &request,
         }
         size_t covered = (spaceEstimate *  numActiveLids) / totalSpace;
         LOG(debug, "covered = %zd", covered);
+
+        SearchReply::Coverage & coverage = reply->coverage;
         coverage.setActive(numActiveLids);
         //TODO this should be calculated with ClusterState calculator.
         coverage.setSoonActive(numActiveLids);
         coverage.setCovered(covered);
+        if (wasLimited) {
+            coverage.degradeMatchPhase();
+            LOG(debug, "was limited, degraded from match phase");
+        }
+        if (my_stats.softDoomed()) {
+            coverage.degradeTimeout();
+            coverage.setCovered(my_stats.docsCovered());
+            LOG(debug, "soft doomed, degraded from timeout covered = %lu", coverage.getCovered()); }
         LOG(debug, "numThreadsPerSearch = %zu. Configured = %d, estimated hits=%d, totalHits=%ld",
             numThreadsPerSearch, _rankSetup->getNumThreadsPerSearch(), estHits, reply->totalHitCount);
     }
@@ -326,19 +316,15 @@ Matcher::match(const SearchRequest &request,
 }
 
 FeatureSet::SP
-Matcher::getSummaryFeatures(const DocsumRequest & req,
-                            ISearchContext & searchCtx,
-                            IAttributeContext & attrCtx,
-                            SessionManager &sessionMgr)
+Matcher::getSummaryFeatures(const DocsumRequest & req, ISearchContext & searchCtx,
+                            IAttributeContext & attrCtx, SessionManager &sessionMgr)
 {
     return getFeatureSet(req, searchCtx, attrCtx, sessionMgr, true);
 }
 
 FeatureSet::SP
-Matcher::getRankFeatures(const DocsumRequest & req,
-                         ISearchContext & searchCtx,
-                         IAttributeContext & attrCtx,
-                         SessionManager &sessionMgr)
+Matcher::getRankFeatures(const DocsumRequest & req, ISearchContext & searchCtx,
+                         IAttributeContext & attrCtx, SessionManager &sessionMgr)
 {
     return getFeatureSet(req, searchCtx, attrCtx, sessionMgr, false);
 }
diff --git a/searchcore/src/vespa/searchcore/proton/matching/matching_stats.cpp b/searchcore/src/vespa/searchcore/proton/matching/matching_stats.cpp
index de46386d6e1..7ea417bb7d2 100644
--- a/searchcore/src/vespa/searchcore/proton/matching/matching_stats.cpp
+++ b/searchcore/src/vespa/searchcore/proton/matching/matching_stats.cpp
@@ -18,6 +18,7 @@ MatchingStats::Partition &get_writable_partition(std::vector<MatchingStats::Part
 MatchingStats::MatchingStats()
     : _queries(0),
       _limited_queries(0),
+      _docsCovered(0),
       _docsMatched(0),
       _docsRanked(0),
       _docsReRanked(0),
@@ -31,13 +32,14 @@ MatchingStats::MatchingStats()
       _partitions()
 { }
 
-MatchingStats::~MatchingStats() { }
+MatchingStats::~MatchingStats() = default;
 
 MatchingStats &
 MatchingStats::merge_partition(const Partition &partition, size_t id)
 {
     get_writable_partition(_partitions, id) = partition;
 
+    _docsCovered += partition.docsCovered();
     _docsMatched += partition.docsMatched();
     _docsRanked += partition.docsRanked();
     _docsReRanked += partition.docsReRanked();
@@ -51,10 +53,10 @@ MatchingStats::merge_partition(const Partition &partition, size_t id)
 MatchingStats &
 MatchingStats::add(const MatchingStats &rhs)
 {
-
     _queries += rhs._queries;
     _limited_queries += rhs._limited_queries;
 
+    _docsCovered += rhs._docsCovered;
     _docsMatched += rhs._docsMatched;
     _docsRanked += rhs._docsRanked;
     _docsReRanked += rhs._docsReRanked;
diff --git a/searchcore/src/vespa/searchcore/proton/matching/matching_stats.h b/searchcore/src/vespa/searchcore/proton/matching/matching_stats.h
index 99084098f6f..e4578547e60 100644
--- a/searchcore/src/vespa/searchcore/proton/matching/matching_stats.h
+++ b/searchcore/src/vespa/searchcore/proton/matching/matching_stats.h
@@ -37,6 +37,7 @@ public:
      * thread.
      **/
     class Partition {
+        size_t _docsCovered;
         size_t _docsMatched;
         size_t _docsRanked;
         size_t _docsReRanked;
@@ -45,13 +46,16 @@ public:
         Avg    _wait_time;
     public:
         Partition()
-            : _docsMatched(0),
+            : _docsCovered(0),
+              _docsMatched(0),
               _docsRanked(0),
               _docsReRanked(0),
               _softDoomed(0),
               _active_time(),
               _wait_time() { }
 
+        Partition &docsCovered(size_t value) { _docsCovered = value; return *this; }
+        size_t docsCovered() const { return _docsCovered; }
         Partition &docsMatched(size_t value) { _docsMatched = value; return *this; }
         size_t docsMatched() const { return _docsMatched; }
         Partition &docsRanked(size_t value) { _docsRanked = value; return *this; }
@@ -69,6 +73,7 @@ public:
         size_t wait_time_count() const { return _wait_time.count(); }
 
         Partition &add(const Partition &rhs) {
+            _docsCovered += rhs.docsCovered();
             _docsMatched += rhs._docsMatched;
             _docsRanked += rhs._docsRanked;
             _docsReRanked += rhs._docsReRanked;
@@ -83,6 +88,7 @@ public:
 private:
     size_t                 _queries;
     size_t                 _limited_queries;
+    size_t                 _docsCovered;
     size_t                 _docsMatched;
     size_t                 _docsRanked;
     size_t                 _docsReRanked;
@@ -109,6 +115,9 @@ public:
     MatchingStats &limited_queries(size_t value) { _limited_queries = value; return *this; }
     size_t limited_queries() const { return _limited_queries; }
 
+    MatchingStats &docsCovered(size_t value) { _docsCovered = value; return *this; }
+    size_t docsCovered() const { return _docsCovered; }
+
     MatchingStats &docsMatched(size_t value) { _docsMatched = value; return *this; }
     size_t docsMatched() const { return _docsMatched; }