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Merged
gridnevvvit merged 1 commit into from
Dec 2, 2025
Merged

quicker result rows release to avoid potential overload #29362

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139 changes: 81 additions & 58 deletions ydb/core/kqp/runtime/kqp_stream_lookup_worker.cpp
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Original file line number Diff line number Diff line change
Expand Up @@ -572,17 +572,23 @@ class TKqpJoinRows : public TKqpStreamLookupWorker {
row.ComputeSize = NYql::NDq::TDqDataSerializer::EstimateSize(row.Data, GetLeftRowType());
ui64 joinKeyId = JoinKeySeqNo++;
TOwnedCellVec cellVec(std::move(joinKeyCells));
ResultRowsBySeqNo[rowSeqNo].AcceptLeftRow(std::move(row), rowSeqNo, firstRow, lastRow);
auto [resIt, _] = ResultRowsBySeqNo.emplace(
rowSeqNo, TResultBatch(KeepRowsOrder() ? nullptr : &FlushedResultRows, HolderFactory, rowSeqNo, std::move(row)));
resIt->second.AcceptLeftRow(firstRow, lastRow);
if (!IsKeyAllowed(cellVec)) {
ResultRowsBySeqNo[rowSeqNo].AddJoinKey(joinKeyId);
ResultRowsBySeqNo[rowSeqNo].OnJoinKeyFinished(HolderFactory, joinKeyId);
resIt->second.AddJoinKey(joinKeyId);
resIt->second.OnJoinKeyFinished(joinKeyId);
if (resIt->second.Completed()) {
ResultRowsBySeqNo.erase(resIt);
}

} else {
auto [it, success] = PendingLeftRowsByKey.emplace(cellVec, TJoinKeyInfo(joinKeyId));
if (success) {
UnprocessedRows.emplace_back(TUnprocessedLeftRow(cellVec));
}
it->second.ResultSeqNos.push_back(rowSeqNo);
ResultRowsBySeqNo[rowSeqNo].AddJoinKey(it->second.JoinKeyId);
resIt->second.AddJoinKey(it->second.JoinKeyId);
}
}

Expand Down Expand Up @@ -764,7 +770,12 @@ class TKqpJoinRows : public TKqpStreamLookupWorker {
auto it = PendingLeftRowsByKey.find(unprocessedRow.JoinKey);
YQL_ENSURE(it != PendingLeftRowsByKey.end());
for(ui64 seqNo : it->second.ResultSeqNos) {
ResultRowsBySeqNo.at(seqNo).OnJoinKeyFinished(HolderFactory, it->second.JoinKeyId);
auto resultRowsIt = ResultRowsBySeqNo.find(seqNo);
YQL_ENSURE(resultRowsIt != ResultRowsBySeqNo.end());
resultRowsIt->second.OnJoinKeyFinished(it->second.JoinKeyId);
if (resultRowsIt->second.Completed()) {
ResultRowsBySeqNo.erase(resultRowsIt);
}
}
PendingLeftRowsByKey.erase(it);
}
Expand Down Expand Up @@ -813,13 +824,9 @@ class TKqpJoinRows : public TKqpStreamLookupWorker {
}

bool HasPendingResults() final {
auto nextSeqNo = KeepRowsOrder() ? ResultRowsBySeqNo.find(CurrentResultSeqNo) : ResultRowsBySeqNo.begin();

if (nextSeqNo != ResultRowsBySeqNo.end() && !nextSeqNo->second.Rows.empty()) {
return true;
}
OrderedFlushRows();

return false;
return !FlushedResultRows.empty();
}

void AddResult(TShardReadResult result) final {
Expand All @@ -846,8 +853,7 @@ class TKqpJoinRows : public TKqpStreamLookupWorker {
auto rightRow = leftRowIt->second.AttachRightRow(HolderFactory, Settings, ReadColumns, row);
for(auto seqNo: leftRowIt->second.ResultSeqNos) {
auto& resultRows = ResultRowsBySeqNo.at(seqNo);
resultRows.TryBuildResultRow(HolderFactory, rightRow);
YQL_ENSURE(IsRowSeqNoValid(seqNo));
resultRows.TryBuildResultRow(rightRow);
}
}

Expand All @@ -861,7 +867,12 @@ class TKqpJoinRows : public TKqpStreamLookupWorker {
YQL_ENSURE(leftRowIt != PendingLeftRowsByKey.end());
if (leftRowIt->second.FinishReadId(record.GetReadId())) {
for(ui64 seqNo : leftRowIt->second.ResultSeqNos) {
ResultRowsBySeqNo.at(seqNo).OnJoinKeyFinished(HolderFactory, leftRowIt->second.JoinKeyId);
auto resultRowsIt = ResultRowsBySeqNo.find(seqNo);
YQL_ENSURE(resultRowsIt != ResultRowsBySeqNo.end());
resultRowsIt->second.OnJoinKeyFinished(leftRowIt->second.JoinKeyId);
if (resultRowsIt->second.Completed()) {
ResultRowsBySeqNo.erase(resultRowsIt);
}
}

PendingLeftRowsByKey.erase(leftRowIt);
Expand All @@ -878,7 +889,8 @@ class TKqpJoinRows : public TKqpStreamLookupWorker {
&& UnprocessedKeys.empty()
&& ReadStateByReadId.empty()
&& ResultRowsBySeqNo.empty()
&& PendingLeftRowsByKey.empty();
&& PendingLeftRowsByKey.empty()
&& FlushedResultRows.empty();
}

void ResetRowsProcessing(ui64 readId) final {
Expand Down Expand Up @@ -919,45 +931,46 @@ class TKqpJoinRows : public TKqpStreamLookupWorker {
ReadStateByReadId.erase(readIt);
}

TReadResultStats ReplyResult(NKikimr::NMiniKQL::TUnboxedValueBatch& batch, i64 freeSpace) final {
TReadResultStats resultStats;
batch.clear();
void OrderedFlushRows() {
if (!KeepRowsOrder()) {
return;
}

auto getNextResult = [&]() {
if (!KeepRowsOrder()) {
return ResultRowsBySeqNo.begin();
while(true) {
auto it = ResultRowsBySeqNo.find(CurrentResultSeqNo);
if (it == ResultRowsBySeqNo.end()) {
break;
}

return ResultRowsBySeqNo.find(CurrentResultSeqNo);
};

while (!resultStats.SizeLimitExceeded) {
auto resultIt = getNextResult();
if (resultIt == ResultRowsBySeqNo.end()) {
it->second.FlushRows(FlushedResultRows);
if (!it->second.Completed()) {
break;
}

auto& result = resultIt->second;
++CurrentResultSeqNo;
ResultRowsBySeqNo.erase(it);
}

while(!result.Rows.empty()) {
TResultBatch::TResultRow& row = result.Rows.front();
return;
}

if (resultStats.ResultRowsCount && resultStats.ResultBytesCount + row.Stats.ResultBytesCount > (ui64)freeSpace) {
resultStats.SizeLimitExceeded = true;
break;
}
TReadResultStats ReplyResult(NKikimr::NMiniKQL::TUnboxedValueBatch& batch, i64 freeSpace) final {
TReadResultStats resultStats;
batch.clear();

batch.emplace_back(std::move(row.Data));
result.Rows.pop_front();
resultStats.Add(row.Stats);
}
OrderedFlushRows();

if (result.Completed()) {
ResultRowsBySeqNo.erase(resultIt);
++CurrentResultSeqNo;
} else {
while (!resultStats.SizeLimitExceeded && !FlushedResultRows.empty()) {
TResultBatch::TResultRow& row = FlushedResultRows.front();

if (resultStats.ResultRowsCount && resultStats.ResultBytesCount + row.Stats.ResultBytesCount > (ui64)freeSpace) {
resultStats.SizeLimitExceeded = true;
break;
}

batch.emplace_back(std::move(row.Data));
FlushedResultRows.pop_front();
resultStats.Add(row.Stats);
}

return resultStats;
Expand All @@ -971,6 +984,7 @@ class TKqpJoinRows : public TKqpStreamLookupWorker {
UnprocessedRows.clear();
PendingLeftRowsByKey.clear();
ResultRowsBySeqNo.clear();
FlushedResultRows.clear();
}
private:
struct TJoinKeyInfo {
Expand Down Expand Up @@ -1033,6 +1047,16 @@ class TKqpJoinRows : public TKqpStreamLookupWorker {
TReadResultStats Stats;
};

explicit TResultBatch(std::deque<TResultRow>* result, const NMiniKQL::THolderFactory& holderFactory, ui64 seqNo, TSizedUnboxedValue&& leftRow)
: Result(result)
, HolderFactory(holderFactory)
, RowSeqNo(seqNo)
, LeftRow(std::move(leftRow))
{
}

std::deque<TResultRow>* Result;
const NMiniKQL::THolderFactory& HolderFactory;
std::deque<TResultRow> Rows;
std::unordered_set<ui64> PendingJoinKeys;
ui32 FirstUnprocessedRow = 0;
Expand All @@ -1048,21 +1072,19 @@ class TKqpJoinRows : public TKqpStreamLookupWorker {
return LastRow && PendingJoinKeys.empty();
}

void OnJoinKeyFinished(const NMiniKQL::THolderFactory& HolderFactory, ui64 joinKeyId) {
void OnJoinKeyFinished(ui64 joinKeyId) {
auto it = PendingJoinKeys.find(joinKeyId);
if (it != PendingJoinKeys.end()) {
PendingJoinKeys.erase(joinKeyId);
TryBuildResultRow(HolderFactory);
TryBuildResultRow();
}
}

void AddJoinKey(ui64 joinKeyId) {
PendingJoinKeys.emplace(joinKeyId);
}

void AcceptLeftRow(TSizedUnboxedValue&& leftRow, ui64 seqNo, bool firstRow, bool lastRow) {
RowSeqNo = seqNo;
LeftRow = std::move(leftRow);
void AcceptLeftRow(bool firstRow, bool lastRow) {
if (firstRow)
FirstRow = true;

Expand All @@ -1074,7 +1096,12 @@ class TKqpJoinRows : public TKqpStreamLookupWorker {
return Rows.empty() && FirstRow && LastRow && PendingJoinKeys.empty();
}

void TryBuildResultRow(const NMiniKQL::THolderFactory& HolderFactory, std::optional<TSizedUnboxedValue> row = {}) {
void FlushRows(std::deque<TResultRow>& externalStorage) {
externalStorage.insert(externalStorage.end(), Rows.begin(), Rows.end());
Rows.clear();
}

void TryBuildResultRow(std::optional<TSizedUnboxedValue> row = {}) {
if (RightRow.Data.HasValue() || ProcessedAllJoinKeys()) {
TReadResultStats rowStats;
NUdf::TUnboxedValue resultRow;
Expand All @@ -1094,7 +1121,11 @@ class TKqpJoinRows : public TKqpStreamLookupWorker {
rowStats.ResultBytesCount += LeftRow.ComputeSize + RightRow.ComputeSize;

++ProcessedRows;
Rows.emplace_back(std::move(resultRow), std::move(rowStats));
if (Result) {
Result->emplace_back(std::move(resultRow), std::move(rowStats));
} else {
Rows.emplace_back(std::move(resultRow), std::move(rowStats));
}
}

if (row.has_value()) {
Expand All @@ -1111,15 +1142,6 @@ class TKqpJoinRows : public TKqpStreamLookupWorker {
return Settings.KeepRowsOrder;
}

bool IsRowSeqNoValid(const ui64& seqNo) const {
if (!KeepRowsOrder()) {
return true;
}

// we should check row seqNo only if we need to keep the order
return seqNo >= CurrentResultSeqNo;
}

void FillReadRequest(ui64 readId, THolder<TEvDataShard::TEvRead>& request, const std::vector<TOwnedTableRange>& ranges) {
auto& record = request->Record;

Expand Down Expand Up @@ -1210,6 +1232,7 @@ class TKqpJoinRows : public TKqpStreamLookupWorker {
std::unordered_map<ui64, TReadState> ReadStateByReadId;
absl::flat_hash_map<TOwnedCellVec, TJoinKeyInfo, NKikimr::TCellVectorsHash, NKikimr::TCellVectorsEquals> PendingLeftRowsByKey;
std::unordered_map<ui64, TResultBatch> ResultRowsBySeqNo;
std::deque<TResultBatch::TResultRow> FlushedResultRows;
ui64 InputRowSeqNo = 0;
ui64 InputRowSeqNoLast = 0;
ui64 JoinKeySeqNo = 0;
Expand Down
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