You are viewing a plain text version of this content. The canonical link for it is here.
Posted to commits@hbase.apache.org by gi...@apache.org on 2017/05/16 14:59:27 UTC
[13/42] hbase-site git commit: Published site at
82d554e3783372cc6b05489452c815b57c06f6cd.
http://git-wip-us.apache.org/repos/asf/hbase-site/blob/de34004c/devapidocs/src-html/org/apache/hadoop/hbase/regionserver/StoreScanner.StoreScannerCompactionRace.html
----------------------------------------------------------------------
diff --git a/devapidocs/src-html/org/apache/hadoop/hbase/regionserver/StoreScanner.StoreScannerCompactionRace.html b/devapidocs/src-html/org/apache/hadoop/hbase/regionserver/StoreScanner.StoreScannerCompactionRace.html
index 1639da5..14c7dd6 100644
--- a/devapidocs/src-html/org/apache/hadoop/hbase/regionserver/StoreScanner.StoreScannerCompactionRace.html
+++ b/devapidocs/src-html/org/apache/hadoop/hbase/regionserver/StoreScanner.StoreScannerCompactionRace.html
@@ -154,7 +154,7 @@
<span class="sourceLineNo">146</span> private volatile boolean flushed = false;<a name="line.146"></a>
<span class="sourceLineNo">147</span> // generally we get one file from a flush<a name="line.147"></a>
<span class="sourceLineNo">148</span> private final List<StoreFile> flushedStoreFiles = new ArrayList<>(1);<a name="line.148"></a>
-<span class="sourceLineNo">149</span> // generally we get one memstroe scanner from a flush<a name="line.149"></a>
+<span class="sourceLineNo">149</span> // generally we get one memstore scanner from a flush<a name="line.149"></a>
<span class="sourceLineNo">150</span> private final List<KeyValueScanner> memStoreScannersAfterFlush = new ArrayList<>(1);<a name="line.150"></a>
<span class="sourceLineNo">151</span> // The current list of scanners<a name="line.151"></a>
<span class="sourceLineNo">152</span> private final List<KeyValueScanner> currentScanners = new ArrayList<>();<a name="line.152"></a>
@@ -547,476 +547,476 @@
<span class="sourceLineNo">539</span> if (scannerContext == null) {<a name="line.539"></a>
<span class="sourceLineNo">540</span> throw new IllegalArgumentException("Scanner context cannot be null");<a name="line.540"></a>
<span class="sourceLineNo">541</span> }<a name="line.541"></a>
-<span class="sourceLineNo">542</span> trySwitchToStreamRead();<a name="line.542"></a>
-<span class="sourceLineNo">543</span> if (checkFlushed() && reopenAfterFlush()) {<a name="line.543"></a>
-<span class="sourceLineNo">544</span> return scannerContext.setScannerState(NextState.MORE_VALUES).hasMoreValues();<a name="line.544"></a>
-<span class="sourceLineNo">545</span> }<a name="line.545"></a>
-<span class="sourceLineNo">546</span><a name="line.546"></a>
-<span class="sourceLineNo">547</span> // if the heap was left null, then the scanners had previously run out anyways, close and<a name="line.547"></a>
-<span class="sourceLineNo">548</span> // return.<a name="line.548"></a>
-<span class="sourceLineNo">549</span> if (this.heap == null) {<a name="line.549"></a>
-<span class="sourceLineNo">550</span> // By this time partial close should happened because already heap is null<a name="line.550"></a>
-<span class="sourceLineNo">551</span> close(false);// Do all cleanup except heap.close()<a name="line.551"></a>
-<span class="sourceLineNo">552</span> return scannerContext.setScannerState(NextState.NO_MORE_VALUES).hasMoreValues();<a name="line.552"></a>
-<span class="sourceLineNo">553</span> }<a name="line.553"></a>
-<span class="sourceLineNo">554</span><a name="line.554"></a>
-<span class="sourceLineNo">555</span> Cell cell = this.heap.peek();<a name="line.555"></a>
-<span class="sourceLineNo">556</span> if (cell == null) {<a name="line.556"></a>
-<span class="sourceLineNo">557</span> close(false);// Do all cleanup except heap.close()<a name="line.557"></a>
-<span class="sourceLineNo">558</span> return scannerContext.setScannerState(NextState.NO_MORE_VALUES).hasMoreValues();<a name="line.558"></a>
-<span class="sourceLineNo">559</span> }<a name="line.559"></a>
-<span class="sourceLineNo">560</span><a name="line.560"></a>
-<span class="sourceLineNo">561</span> // only call setRow if the row changes; avoids confusing the query matcher<a name="line.561"></a>
-<span class="sourceLineNo">562</span> // if scanning intra-row<a name="line.562"></a>
-<span class="sourceLineNo">563</span><a name="line.563"></a>
-<span class="sourceLineNo">564</span> // If no limits exists in the scope LimitScope.Between_Cells then we are sure we are changing<a name="line.564"></a>
-<span class="sourceLineNo">565</span> // rows. Else it is possible we are still traversing the same row so we must perform the row<a name="line.565"></a>
-<span class="sourceLineNo">566</span> // comparison.<a name="line.566"></a>
-<span class="sourceLineNo">567</span> if (!scannerContext.hasAnyLimit(LimitScope.BETWEEN_CELLS) || matcher.currentRow() == null) {<a name="line.567"></a>
-<span class="sourceLineNo">568</span> this.countPerRow = 0;<a name="line.568"></a>
-<span class="sourceLineNo">569</span> matcher.setToNewRow(cell);<a name="line.569"></a>
-<span class="sourceLineNo">570</span> }<a name="line.570"></a>
-<span class="sourceLineNo">571</span><a name="line.571"></a>
-<span class="sourceLineNo">572</span> // Clear progress away unless invoker has indicated it should be kept.<a name="line.572"></a>
-<span class="sourceLineNo">573</span> if (!scannerContext.getKeepProgress()) {<a name="line.573"></a>
-<span class="sourceLineNo">574</span> scannerContext.clearProgress();<a name="line.574"></a>
-<span class="sourceLineNo">575</span> }<a name="line.575"></a>
-<span class="sourceLineNo">576</span><a name="line.576"></a>
-<span class="sourceLineNo">577</span> // Only do a sanity-check if store and comparator are available.<a name="line.577"></a>
-<span class="sourceLineNo">578</span> CellComparator comparator = store != null ? store.getComparator() : null;<a name="line.578"></a>
-<span class="sourceLineNo">579</span><a name="line.579"></a>
-<span class="sourceLineNo">580</span> int count = 0;<a name="line.580"></a>
-<span class="sourceLineNo">581</span> long totalBytesRead = 0;<a name="line.581"></a>
-<span class="sourceLineNo">582</span><a name="line.582"></a>
-<span class="sourceLineNo">583</span> LOOP: do {<a name="line.583"></a>
-<span class="sourceLineNo">584</span> // Update and check the time limit based on the configured value of cellsPerTimeoutCheck<a name="line.584"></a>
-<span class="sourceLineNo">585</span> if ((kvsScanned % cellsPerHeartbeatCheck == 0)) {<a name="line.585"></a>
-<span class="sourceLineNo">586</span> scannerContext.updateTimeProgress();<a name="line.586"></a>
-<span class="sourceLineNo">587</span> if (scannerContext.checkTimeLimit(LimitScope.BETWEEN_CELLS)) {<a name="line.587"></a>
-<span class="sourceLineNo">588</span> return scannerContext.setScannerState(NextState.TIME_LIMIT_REACHED).hasMoreValues();<a name="line.588"></a>
-<span class="sourceLineNo">589</span> }<a name="line.589"></a>
-<span class="sourceLineNo">590</span> }<a name="line.590"></a>
-<span class="sourceLineNo">591</span> // Do object compare - we set prevKV from the same heap.<a name="line.591"></a>
-<span class="sourceLineNo">592</span> if (prevCell != cell) {<a name="line.592"></a>
-<span class="sourceLineNo">593</span> ++kvsScanned;<a name="line.593"></a>
-<span class="sourceLineNo">594</span> }<a name="line.594"></a>
-<span class="sourceLineNo">595</span> checkScanOrder(prevCell, cell, comparator);<a name="line.595"></a>
-<span class="sourceLineNo">596</span> int cellSize = CellUtil.estimatedSerializedSizeOf(cell);<a name="line.596"></a>
-<span class="sourceLineNo">597</span> bytesRead += cellSize;<a name="line.597"></a>
-<span class="sourceLineNo">598</span> prevCell = cell;<a name="line.598"></a>
-<span class="sourceLineNo">599</span> ScanQueryMatcher.MatchCode qcode = matcher.match(cell);<a name="line.599"></a>
-<span class="sourceLineNo">600</span> switch (qcode) {<a name="line.600"></a>
-<span class="sourceLineNo">601</span> case INCLUDE:<a name="line.601"></a>
-<span class="sourceLineNo">602</span> case INCLUDE_AND_SEEK_NEXT_ROW:<a name="line.602"></a>
-<span class="sourceLineNo">603</span> case INCLUDE_AND_SEEK_NEXT_COL:<a name="line.603"></a>
-<span class="sourceLineNo">604</span><a name="line.604"></a>
-<span class="sourceLineNo">605</span> Filter f = matcher.getFilter();<a name="line.605"></a>
-<span class="sourceLineNo">606</span> if (f != null) {<a name="line.606"></a>
-<span class="sourceLineNo">607</span> cell = f.transformCell(cell);<a name="line.607"></a>
-<span class="sourceLineNo">608</span> }<a name="line.608"></a>
-<span class="sourceLineNo">609</span><a name="line.609"></a>
-<span class="sourceLineNo">610</span> this.countPerRow++;<a name="line.610"></a>
-<span class="sourceLineNo">611</span> if (storeLimit > -1 && this.countPerRow > (storeLimit + storeOffset)) {<a name="line.611"></a>
-<span class="sourceLineNo">612</span> // do what SEEK_NEXT_ROW does.<a name="line.612"></a>
-<span class="sourceLineNo">613</span> if (!matcher.moreRowsMayExistAfter(cell)) {<a name="line.613"></a>
-<span class="sourceLineNo">614</span> close(false);// Do all cleanup except heap.close()<a name="line.614"></a>
-<span class="sourceLineNo">615</span> return scannerContext.setScannerState(NextState.NO_MORE_VALUES).hasMoreValues();<a name="line.615"></a>
-<span class="sourceLineNo">616</span> }<a name="line.616"></a>
-<span class="sourceLineNo">617</span> matcher.clearCurrentRow();<a name="line.617"></a>
-<span class="sourceLineNo">618</span> seekToNextRow(cell);<a name="line.618"></a>
-<span class="sourceLineNo">619</span> break LOOP;<a name="line.619"></a>
-<span class="sourceLineNo">620</span> }<a name="line.620"></a>
-<span class="sourceLineNo">621</span><a name="line.621"></a>
-<span class="sourceLineNo">622</span> // add to results only if we have skipped #storeOffset kvs<a name="line.622"></a>
-<span class="sourceLineNo">623</span> // also update metric accordingly<a name="line.623"></a>
-<span class="sourceLineNo">624</span> if (this.countPerRow > storeOffset) {<a name="line.624"></a>
-<span class="sourceLineNo">625</span> outResult.add(cell);<a name="line.625"></a>
-<span class="sourceLineNo">626</span><a name="line.626"></a>
-<span class="sourceLineNo">627</span> // Update local tracking information<a name="line.627"></a>
-<span class="sourceLineNo">628</span> count++;<a name="line.628"></a>
-<span class="sourceLineNo">629</span> totalBytesRead += cellSize;<a name="line.629"></a>
-<span class="sourceLineNo">630</span><a name="line.630"></a>
-<span class="sourceLineNo">631</span> // Update the progress of the scanner context<a name="line.631"></a>
-<span class="sourceLineNo">632</span> scannerContext.incrementSizeProgress(cellSize, CellUtil.estimatedHeapSizeOf(cell));<a name="line.632"></a>
-<span class="sourceLineNo">633</span> scannerContext.incrementBatchProgress(1);<a name="line.633"></a>
-<span class="sourceLineNo">634</span><a name="line.634"></a>
-<span class="sourceLineNo">635</span> if (matcher.isUserScan() && totalBytesRead > maxRowSize) {<a name="line.635"></a>
-<span class="sourceLineNo">636</span> throw new RowTooBigException(<a name="line.636"></a>
-<span class="sourceLineNo">637</span> "Max row size allowed: " + maxRowSize + ", but the row is bigger than that.");<a name="line.637"></a>
-<span class="sourceLineNo">638</span> }<a name="line.638"></a>
-<span class="sourceLineNo">639</span> }<a name="line.639"></a>
-<span class="sourceLineNo">640</span><a name="line.640"></a>
-<span class="sourceLineNo">641</span> if (qcode == ScanQueryMatcher.MatchCode.INCLUDE_AND_SEEK_NEXT_ROW) {<a name="line.641"></a>
-<span class="sourceLineNo">642</span> if (!matcher.moreRowsMayExistAfter(cell)) {<a name="line.642"></a>
-<span class="sourceLineNo">643</span> close(false);// Do all cleanup except heap.close()<a name="line.643"></a>
-<span class="sourceLineNo">644</span> return scannerContext.setScannerState(NextState.NO_MORE_VALUES).hasMoreValues();<a name="line.644"></a>
-<span class="sourceLineNo">645</span> }<a name="line.645"></a>
-<span class="sourceLineNo">646</span> matcher.clearCurrentRow();<a name="line.646"></a>
-<span class="sourceLineNo">647</span> seekOrSkipToNextRow(cell);<a name="line.647"></a>
-<span class="sourceLineNo">648</span> } else if (qcode == ScanQueryMatcher.MatchCode.INCLUDE_AND_SEEK_NEXT_COL) {<a name="line.648"></a>
-<span class="sourceLineNo">649</span> seekOrSkipToNextColumn(cell);<a name="line.649"></a>
-<span class="sourceLineNo">650</span> } else {<a name="line.650"></a>
-<span class="sourceLineNo">651</span> this.heap.next();<a name="line.651"></a>
-<span class="sourceLineNo">652</span> }<a name="line.652"></a>
-<span class="sourceLineNo">653</span><a name="line.653"></a>
-<span class="sourceLineNo">654</span> if (scannerContext.checkBatchLimit(LimitScope.BETWEEN_CELLS)) {<a name="line.654"></a>
-<span class="sourceLineNo">655</span> break LOOP;<a name="line.655"></a>
-<span class="sourceLineNo">656</span> }<a name="line.656"></a>
-<span class="sourceLineNo">657</span> if (scannerContext.checkSizeLimit(LimitScope.BETWEEN_CELLS)) {<a name="line.657"></a>
-<span class="sourceLineNo">658</span> break LOOP;<a name="line.658"></a>
-<span class="sourceLineNo">659</span> }<a name="line.659"></a>
-<span class="sourceLineNo">660</span> continue;<a name="line.660"></a>
-<span class="sourceLineNo">661</span><a name="line.661"></a>
-<span class="sourceLineNo">662</span> case DONE:<a name="line.662"></a>
-<span class="sourceLineNo">663</span> // Optimization for Gets! If DONE, no more to get on this row, early exit!<a name="line.663"></a>
-<span class="sourceLineNo">664</span> if (get) {<a name="line.664"></a>
-<span class="sourceLineNo">665</span> // Then no more to this row... exit.<a name="line.665"></a>
-<span class="sourceLineNo">666</span> close(false);// Do all cleanup except heap.close()<a name="line.666"></a>
-<span class="sourceLineNo">667</span> return scannerContext.setScannerState(NextState.NO_MORE_VALUES).hasMoreValues();<a name="line.667"></a>
-<span class="sourceLineNo">668</span> }<a name="line.668"></a>
-<span class="sourceLineNo">669</span> matcher.clearCurrentRow();<a name="line.669"></a>
-<span class="sourceLineNo">670</span> return scannerContext.setScannerState(NextState.MORE_VALUES).hasMoreValues();<a name="line.670"></a>
-<span class="sourceLineNo">671</span><a name="line.671"></a>
-<span class="sourceLineNo">672</span> case DONE_SCAN:<a name="line.672"></a>
-<span class="sourceLineNo">673</span> close(false);// Do all cleanup except heap.close()<a name="line.673"></a>
-<span class="sourceLineNo">674</span> return scannerContext.setScannerState(NextState.NO_MORE_VALUES).hasMoreValues();<a name="line.674"></a>
-<span class="sourceLineNo">675</span><a name="line.675"></a>
-<span class="sourceLineNo">676</span> case SEEK_NEXT_ROW:<a name="line.676"></a>
-<span class="sourceLineNo">677</span> // This is just a relatively simple end of scan fix, to short-cut end<a name="line.677"></a>
-<span class="sourceLineNo">678</span> // us if there is an endKey in the scan.<a name="line.678"></a>
-<span class="sourceLineNo">679</span> if (!matcher.moreRowsMayExistAfter(cell)) {<a name="line.679"></a>
-<span class="sourceLineNo">680</span> close(false);// Do all cleanup except heap.close()<a name="line.680"></a>
-<span class="sourceLineNo">681</span> return scannerContext.setScannerState(NextState.NO_MORE_VALUES).hasMoreValues();<a name="line.681"></a>
-<span class="sourceLineNo">682</span> }<a name="line.682"></a>
-<span class="sourceLineNo">683</span> matcher.clearCurrentRow();<a name="line.683"></a>
-<span class="sourceLineNo">684</span> seekOrSkipToNextRow(cell);<a name="line.684"></a>
-<span class="sourceLineNo">685</span> break;<a name="line.685"></a>
-<span class="sourceLineNo">686</span><a name="line.686"></a>
-<span class="sourceLineNo">687</span> case SEEK_NEXT_COL:<a name="line.687"></a>
-<span class="sourceLineNo">688</span> seekOrSkipToNextColumn(cell);<a name="line.688"></a>
-<span class="sourceLineNo">689</span> break;<a name="line.689"></a>
-<span class="sourceLineNo">690</span><a name="line.690"></a>
-<span class="sourceLineNo">691</span> case SKIP:<a name="line.691"></a>
-<span class="sourceLineNo">692</span> this.heap.next();<a name="line.692"></a>
-<span class="sourceLineNo">693</span> break;<a name="line.693"></a>
-<span class="sourceLineNo">694</span><a name="line.694"></a>
-<span class="sourceLineNo">695</span> case SEEK_NEXT_USING_HINT:<a name="line.695"></a>
-<span class="sourceLineNo">696</span> Cell nextKV = matcher.getNextKeyHint(cell);<a name="line.696"></a>
-<span class="sourceLineNo">697</span> if (nextKV != null) {<a name="line.697"></a>
-<span class="sourceLineNo">698</span> seekAsDirection(nextKV);<a name="line.698"></a>
-<span class="sourceLineNo">699</span> } else {<a name="line.699"></a>
-<span class="sourceLineNo">700</span> heap.next();<a name="line.700"></a>
-<span class="sourceLineNo">701</span> }<a name="line.701"></a>
-<span class="sourceLineNo">702</span> break;<a name="line.702"></a>
-<span class="sourceLineNo">703</span><a name="line.703"></a>
-<span class="sourceLineNo">704</span> default:<a name="line.704"></a>
-<span class="sourceLineNo">705</span> throw new RuntimeException("UNEXPECTED");<a name="line.705"></a>
-<span class="sourceLineNo">706</span> }<a name="line.706"></a>
-<span class="sourceLineNo">707</span> } while ((cell = this.heap.peek()) != null);<a name="line.707"></a>
-<span class="sourceLineNo">708</span><a name="line.708"></a>
-<span class="sourceLineNo">709</span> if (count > 0) {<a name="line.709"></a>
-<span class="sourceLineNo">710</span> return scannerContext.setScannerState(NextState.MORE_VALUES).hasMoreValues();<a name="line.710"></a>
-<span class="sourceLineNo">711</span> }<a name="line.711"></a>
-<span class="sourceLineNo">712</span><a name="line.712"></a>
-<span class="sourceLineNo">713</span> // No more keys<a name="line.713"></a>
-<span class="sourceLineNo">714</span> close(false);// Do all cleanup except heap.close()<a name="line.714"></a>
-<span class="sourceLineNo">715</span> return scannerContext.setScannerState(NextState.NO_MORE_VALUES).hasMoreValues();<a name="line.715"></a>
-<span class="sourceLineNo">716</span> }<a name="line.716"></a>
-<span class="sourceLineNo">717</span><a name="line.717"></a>
-<span class="sourceLineNo">718</span> private void seekOrSkipToNextRow(Cell cell) throws IOException {<a name="line.718"></a>
-<span class="sourceLineNo">719</span> // If it is a Get Scan, then we know that we are done with this row; there are no more<a name="line.719"></a>
-<span class="sourceLineNo">720</span> // rows beyond the current one: don't try to optimize.<a name="line.720"></a>
-<span class="sourceLineNo">721</span> if (!get) {<a name="line.721"></a>
-<span class="sourceLineNo">722</span> if (trySkipToNextRow(cell)) {<a name="line.722"></a>
-<span class="sourceLineNo">723</span> return;<a name="line.723"></a>
-<span class="sourceLineNo">724</span> }<a name="line.724"></a>
-<span class="sourceLineNo">725</span> }<a name="line.725"></a>
-<span class="sourceLineNo">726</span> seekToNextRow(cell);<a name="line.726"></a>
-<span class="sourceLineNo">727</span> }<a name="line.727"></a>
-<span class="sourceLineNo">728</span><a name="line.728"></a>
-<span class="sourceLineNo">729</span> private void seekOrSkipToNextColumn(Cell cell) throws IOException {<a name="line.729"></a>
-<span class="sourceLineNo">730</span> if (!trySkipToNextColumn(cell)) {<a name="line.730"></a>
-<span class="sourceLineNo">731</span> seekAsDirection(matcher.getKeyForNextColumn(cell));<a name="line.731"></a>
-<span class="sourceLineNo">732</span> }<a name="line.732"></a>
-<span class="sourceLineNo">733</span> }<a name="line.733"></a>
-<span class="sourceLineNo">734</span><a name="line.734"></a>
-<span class="sourceLineNo">735</span> /**<a name="line.735"></a>
-<span class="sourceLineNo">736</span> * See if we should actually SEEK or rather just SKIP to the next Cell (see HBASE-13109).<a name="line.736"></a>
-<span class="sourceLineNo">737</span> * ScanQueryMatcher may issue SEEK hints, such as seek to next column, next row,<a name="line.737"></a>
-<span class="sourceLineNo">738</span> * or seek to an arbitrary seek key. This method decides whether a seek is the most efficient<a name="line.738"></a>
-<span class="sourceLineNo">739</span> * _actual_ way to get us to the requested cell (SEEKs are more expensive than SKIP, SKIP,<a name="line.739"></a>
-<span class="sourceLineNo">740</span> * SKIP inside the current, loaded block).<a name="line.740"></a>
-<span class="sourceLineNo">741</span> * It does this by looking at the next indexed key of the current HFile. This key<a name="line.741"></a>
-<span class="sourceLineNo">742</span> * is then compared with the _SEEK_ key, where a SEEK key is an artificial 'last possible key<a name="line.742"></a>
-<span class="sourceLineNo">743</span> * on the row' (only in here, we avoid actually creating a SEEK key; in the compare we work with<a name="line.743"></a>
-<span class="sourceLineNo">744</span> * the current Cell but compare as though it were a seek key; see down in<a name="line.744"></a>
-<span class="sourceLineNo">745</span> * matcher.compareKeyForNextRow, etc). If the compare gets us onto the<a name="line.745"></a>
-<span class="sourceLineNo">746</span> * next block we *_SEEK, otherwise we just SKIP to the next requested cell.<a name="line.746"></a>
-<span class="sourceLineNo">747</span> *<a name="line.747"></a>
-<span class="sourceLineNo">748</span> * <p>Other notes:<a name="line.748"></a>
-<span class="sourceLineNo">749</span> * <ul><a name="line.749"></a>
-<span class="sourceLineNo">750</span> * <li>Rows can straddle block boundaries</li><a name="line.750"></a>
-<span class="sourceLineNo">751</span> * <li>Versions of columns can straddle block boundaries (i.e. column C1 at T1 might be in a<a name="line.751"></a>
-<span class="sourceLineNo">752</span> * different block than column C1 at T2)</li><a name="line.752"></a>
-<span class="sourceLineNo">753</span> * <li>We want to SKIP if the chance is high that we'll find the desired Cell after a<a name="line.753"></a>
-<span class="sourceLineNo">754</span> * few SKIPs...</li><a name="line.754"></a>
-<span class="sourceLineNo">755</span> * <li>We want to SEEK when the chance is high that we'll be able to seek<a name="line.755"></a>
-<span class="sourceLineNo">756</span> * past many Cells, especially if we know we need to go to the next block.</li><a name="line.756"></a>
-<span class="sourceLineNo">757</span> * </ul><a name="line.757"></a>
-<span class="sourceLineNo">758</span> * <p>A good proxy (best effort) to determine whether SKIP is better than SEEK is whether<a name="line.758"></a>
-<span class="sourceLineNo">759</span> * we'll likely end up seeking to the next block (or past the next block) to get our next column.<a name="line.759"></a>
-<span class="sourceLineNo">760</span> * Example:<a name="line.760"></a>
-<span class="sourceLineNo">761</span> * <pre><a name="line.761"></a>
-<span class="sourceLineNo">762</span> * | BLOCK 1 | BLOCK 2 |<a name="line.762"></a>
-<span class="sourceLineNo">763</span> * | r1/c1, r1/c2, r1/c3 | r1/c4, r1/c5, r2/c1 |<a name="line.763"></a>
-<span class="sourceLineNo">764</span> * ^ ^<a name="line.764"></a>
-<span class="sourceLineNo">765</span> * | |<a name="line.765"></a>
-<span class="sourceLineNo">766</span> * Next Index Key SEEK_NEXT_ROW (before r2/c1)<a name="line.766"></a>
+<span class="sourceLineNo">542</span> if (checkFlushed() && reopenAfterFlush()) {<a name="line.542"></a>
+<span class="sourceLineNo">543</span> return scannerContext.setScannerState(NextState.MORE_VALUES).hasMoreValues();<a name="line.543"></a>
+<span class="sourceLineNo">544</span> }<a name="line.544"></a>
+<span class="sourceLineNo">545</span><a name="line.545"></a>
+<span class="sourceLineNo">546</span> // if the heap was left null, then the scanners had previously run out anyways, close and<a name="line.546"></a>
+<span class="sourceLineNo">547</span> // return.<a name="line.547"></a>
+<span class="sourceLineNo">548</span> if (this.heap == null) {<a name="line.548"></a>
+<span class="sourceLineNo">549</span> // By this time partial close should happened because already heap is null<a name="line.549"></a>
+<span class="sourceLineNo">550</span> close(false);// Do all cleanup except heap.close()<a name="line.550"></a>
+<span class="sourceLineNo">551</span> return scannerContext.setScannerState(NextState.NO_MORE_VALUES).hasMoreValues();<a name="line.551"></a>
+<span class="sourceLineNo">552</span> }<a name="line.552"></a>
+<span class="sourceLineNo">553</span><a name="line.553"></a>
+<span class="sourceLineNo">554</span> Cell cell = this.heap.peek();<a name="line.554"></a>
+<span class="sourceLineNo">555</span> if (cell == null) {<a name="line.555"></a>
+<span class="sourceLineNo">556</span> close(false);// Do all cleanup except heap.close()<a name="line.556"></a>
+<span class="sourceLineNo">557</span> return scannerContext.setScannerState(NextState.NO_MORE_VALUES).hasMoreValues();<a name="line.557"></a>
+<span class="sourceLineNo">558</span> }<a name="line.558"></a>
+<span class="sourceLineNo">559</span><a name="line.559"></a>
+<span class="sourceLineNo">560</span> // only call setRow if the row changes; avoids confusing the query matcher<a name="line.560"></a>
+<span class="sourceLineNo">561</span> // if scanning intra-row<a name="line.561"></a>
+<span class="sourceLineNo">562</span><a name="line.562"></a>
+<span class="sourceLineNo">563</span> // If no limits exists in the scope LimitScope.Between_Cells then we are sure we are changing<a name="line.563"></a>
+<span class="sourceLineNo">564</span> // rows. Else it is possible we are still traversing the same row so we must perform the row<a name="line.564"></a>
+<span class="sourceLineNo">565</span> // comparison.<a name="line.565"></a>
+<span class="sourceLineNo">566</span> if (!scannerContext.hasAnyLimit(LimitScope.BETWEEN_CELLS) || matcher.currentRow() == null) {<a name="line.566"></a>
+<span class="sourceLineNo">567</span> this.countPerRow = 0;<a name="line.567"></a>
+<span class="sourceLineNo">568</span> matcher.setToNewRow(cell);<a name="line.568"></a>
+<span class="sourceLineNo">569</span> }<a name="line.569"></a>
+<span class="sourceLineNo">570</span><a name="line.570"></a>
+<span class="sourceLineNo">571</span> // Clear progress away unless invoker has indicated it should be kept.<a name="line.571"></a>
+<span class="sourceLineNo">572</span> if (!scannerContext.getKeepProgress()) {<a name="line.572"></a>
+<span class="sourceLineNo">573</span> scannerContext.clearProgress();<a name="line.573"></a>
+<span class="sourceLineNo">574</span> }<a name="line.574"></a>
+<span class="sourceLineNo">575</span><a name="line.575"></a>
+<span class="sourceLineNo">576</span> // Only do a sanity-check if store and comparator are available.<a name="line.576"></a>
+<span class="sourceLineNo">577</span> CellComparator comparator = store != null ? store.getComparator() : null;<a name="line.577"></a>
+<span class="sourceLineNo">578</span><a name="line.578"></a>
+<span class="sourceLineNo">579</span> int count = 0;<a name="line.579"></a>
+<span class="sourceLineNo">580</span> long totalBytesRead = 0;<a name="line.580"></a>
+<span class="sourceLineNo">581</span><a name="line.581"></a>
+<span class="sourceLineNo">582</span> LOOP: do {<a name="line.582"></a>
+<span class="sourceLineNo">583</span> // Update and check the time limit based on the configured value of cellsPerTimeoutCheck<a name="line.583"></a>
+<span class="sourceLineNo">584</span> if ((kvsScanned % cellsPerHeartbeatCheck == 0)) {<a name="line.584"></a>
+<span class="sourceLineNo">585</span> scannerContext.updateTimeProgress();<a name="line.585"></a>
+<span class="sourceLineNo">586</span> if (scannerContext.checkTimeLimit(LimitScope.BETWEEN_CELLS)) {<a name="line.586"></a>
+<span class="sourceLineNo">587</span> return scannerContext.setScannerState(NextState.TIME_LIMIT_REACHED).hasMoreValues();<a name="line.587"></a>
+<span class="sourceLineNo">588</span> }<a name="line.588"></a>
+<span class="sourceLineNo">589</span> }<a name="line.589"></a>
+<span class="sourceLineNo">590</span> // Do object compare - we set prevKV from the same heap.<a name="line.590"></a>
+<span class="sourceLineNo">591</span> if (prevCell != cell) {<a name="line.591"></a>
+<span class="sourceLineNo">592</span> ++kvsScanned;<a name="line.592"></a>
+<span class="sourceLineNo">593</span> }<a name="line.593"></a>
+<span class="sourceLineNo">594</span> checkScanOrder(prevCell, cell, comparator);<a name="line.594"></a>
+<span class="sourceLineNo">595</span> int cellSize = CellUtil.estimatedSerializedSizeOf(cell);<a name="line.595"></a>
+<span class="sourceLineNo">596</span> bytesRead += cellSize;<a name="line.596"></a>
+<span class="sourceLineNo">597</span> prevCell = cell;<a name="line.597"></a>
+<span class="sourceLineNo">598</span> ScanQueryMatcher.MatchCode qcode = matcher.match(cell);<a name="line.598"></a>
+<span class="sourceLineNo">599</span> switch (qcode) {<a name="line.599"></a>
+<span class="sourceLineNo">600</span> case INCLUDE:<a name="line.600"></a>
+<span class="sourceLineNo">601</span> case INCLUDE_AND_SEEK_NEXT_ROW:<a name="line.601"></a>
+<span class="sourceLineNo">602</span> case INCLUDE_AND_SEEK_NEXT_COL:<a name="line.602"></a>
+<span class="sourceLineNo">603</span><a name="line.603"></a>
+<span class="sourceLineNo">604</span> Filter f = matcher.getFilter();<a name="line.604"></a>
+<span class="sourceLineNo">605</span> if (f != null) {<a name="line.605"></a>
+<span class="sourceLineNo">606</span> cell = f.transformCell(cell);<a name="line.606"></a>
+<span class="sourceLineNo">607</span> }<a name="line.607"></a>
+<span class="sourceLineNo">608</span><a name="line.608"></a>
+<span class="sourceLineNo">609</span> this.countPerRow++;<a name="line.609"></a>
+<span class="sourceLineNo">610</span> if (storeLimit > -1 && this.countPerRow > (storeLimit + storeOffset)) {<a name="line.610"></a>
+<span class="sourceLineNo">611</span> // do what SEEK_NEXT_ROW does.<a name="line.611"></a>
+<span class="sourceLineNo">612</span> if (!matcher.moreRowsMayExistAfter(cell)) {<a name="line.612"></a>
+<span class="sourceLineNo">613</span> close(false);// Do all cleanup except heap.close()<a name="line.613"></a>
+<span class="sourceLineNo">614</span> return scannerContext.setScannerState(NextState.NO_MORE_VALUES).hasMoreValues();<a name="line.614"></a>
+<span class="sourceLineNo">615</span> }<a name="line.615"></a>
+<span class="sourceLineNo">616</span> matcher.clearCurrentRow();<a name="line.616"></a>
+<span class="sourceLineNo">617</span> seekToNextRow(cell);<a name="line.617"></a>
+<span class="sourceLineNo">618</span> break LOOP;<a name="line.618"></a>
+<span class="sourceLineNo">619</span> }<a name="line.619"></a>
+<span class="sourceLineNo">620</span><a name="line.620"></a>
+<span class="sourceLineNo">621</span> // add to results only if we have skipped #storeOffset kvs<a name="line.621"></a>
+<span class="sourceLineNo">622</span> // also update metric accordingly<a name="line.622"></a>
+<span class="sourceLineNo">623</span> if (this.countPerRow > storeOffset) {<a name="line.623"></a>
+<span class="sourceLineNo">624</span> outResult.add(cell);<a name="line.624"></a>
+<span class="sourceLineNo">625</span><a name="line.625"></a>
+<span class="sourceLineNo">626</span> // Update local tracking information<a name="line.626"></a>
+<span class="sourceLineNo">627</span> count++;<a name="line.627"></a>
+<span class="sourceLineNo">628</span> totalBytesRead += cellSize;<a name="line.628"></a>
+<span class="sourceLineNo">629</span><a name="line.629"></a>
+<span class="sourceLineNo">630</span> // Update the progress of the scanner context<a name="line.630"></a>
+<span class="sourceLineNo">631</span> scannerContext.incrementSizeProgress(cellSize, CellUtil.estimatedHeapSizeOf(cell));<a name="line.631"></a>
+<span class="sourceLineNo">632</span> scannerContext.incrementBatchProgress(1);<a name="line.632"></a>
+<span class="sourceLineNo">633</span><a name="line.633"></a>
+<span class="sourceLineNo">634</span> if (matcher.isUserScan() && totalBytesRead > maxRowSize) {<a name="line.634"></a>
+<span class="sourceLineNo">635</span> throw new RowTooBigException(<a name="line.635"></a>
+<span class="sourceLineNo">636</span> "Max row size allowed: " + maxRowSize + ", but the row is bigger than that.");<a name="line.636"></a>
+<span class="sourceLineNo">637</span> }<a name="line.637"></a>
+<span class="sourceLineNo">638</span> }<a name="line.638"></a>
+<span class="sourceLineNo">639</span><a name="line.639"></a>
+<span class="sourceLineNo">640</span> if (qcode == ScanQueryMatcher.MatchCode.INCLUDE_AND_SEEK_NEXT_ROW) {<a name="line.640"></a>
+<span class="sourceLineNo">641</span> if (!matcher.moreRowsMayExistAfter(cell)) {<a name="line.641"></a>
+<span class="sourceLineNo">642</span> close(false);// Do all cleanup except heap.close()<a name="line.642"></a>
+<span class="sourceLineNo">643</span> return scannerContext.setScannerState(NextState.NO_MORE_VALUES).hasMoreValues();<a name="line.643"></a>
+<span class="sourceLineNo">644</span> }<a name="line.644"></a>
+<span class="sourceLineNo">645</span> matcher.clearCurrentRow();<a name="line.645"></a>
+<span class="sourceLineNo">646</span> seekOrSkipToNextRow(cell);<a name="line.646"></a>
+<span class="sourceLineNo">647</span> } else if (qcode == ScanQueryMatcher.MatchCode.INCLUDE_AND_SEEK_NEXT_COL) {<a name="line.647"></a>
+<span class="sourceLineNo">648</span> seekOrSkipToNextColumn(cell);<a name="line.648"></a>
+<span class="sourceLineNo">649</span> } else {<a name="line.649"></a>
+<span class="sourceLineNo">650</span> this.heap.next();<a name="line.650"></a>
+<span class="sourceLineNo">651</span> }<a name="line.651"></a>
+<span class="sourceLineNo">652</span><a name="line.652"></a>
+<span class="sourceLineNo">653</span> if (scannerContext.checkBatchLimit(LimitScope.BETWEEN_CELLS)) {<a name="line.653"></a>
+<span class="sourceLineNo">654</span> break LOOP;<a name="line.654"></a>
+<span class="sourceLineNo">655</span> }<a name="line.655"></a>
+<span class="sourceLineNo">656</span> if (scannerContext.checkSizeLimit(LimitScope.BETWEEN_CELLS)) {<a name="line.656"></a>
+<span class="sourceLineNo">657</span> break LOOP;<a name="line.657"></a>
+<span class="sourceLineNo">658</span> }<a name="line.658"></a>
+<span class="sourceLineNo">659</span> continue;<a name="line.659"></a>
+<span class="sourceLineNo">660</span><a name="line.660"></a>
+<span class="sourceLineNo">661</span> case DONE:<a name="line.661"></a>
+<span class="sourceLineNo">662</span> // Optimization for Gets! If DONE, no more to get on this row, early exit!<a name="line.662"></a>
+<span class="sourceLineNo">663</span> if (get) {<a name="line.663"></a>
+<span class="sourceLineNo">664</span> // Then no more to this row... exit.<a name="line.664"></a>
+<span class="sourceLineNo">665</span> close(false);// Do all cleanup except heap.close()<a name="line.665"></a>
+<span class="sourceLineNo">666</span> return scannerContext.setScannerState(NextState.NO_MORE_VALUES).hasMoreValues();<a name="line.666"></a>
+<span class="sourceLineNo">667</span> }<a name="line.667"></a>
+<span class="sourceLineNo">668</span> matcher.clearCurrentRow();<a name="line.668"></a>
+<span class="sourceLineNo">669</span> return scannerContext.setScannerState(NextState.MORE_VALUES).hasMoreValues();<a name="line.669"></a>
+<span class="sourceLineNo">670</span><a name="line.670"></a>
+<span class="sourceLineNo">671</span> case DONE_SCAN:<a name="line.671"></a>
+<span class="sourceLineNo">672</span> close(false);// Do all cleanup except heap.close()<a name="line.672"></a>
+<span class="sourceLineNo">673</span> return scannerContext.setScannerState(NextState.NO_MORE_VALUES).hasMoreValues();<a name="line.673"></a>
+<span class="sourceLineNo">674</span><a name="line.674"></a>
+<span class="sourceLineNo">675</span> case SEEK_NEXT_ROW:<a name="line.675"></a>
+<span class="sourceLineNo">676</span> // This is just a relatively simple end of scan fix, to short-cut end<a name="line.676"></a>
+<span class="sourceLineNo">677</span> // us if there is an endKey in the scan.<a name="line.677"></a>
+<span class="sourceLineNo">678</span> if (!matcher.moreRowsMayExistAfter(cell)) {<a name="line.678"></a>
+<span class="sourceLineNo">679</span> close(false);// Do all cleanup except heap.close()<a name="line.679"></a>
+<span class="sourceLineNo">680</span> return scannerContext.setScannerState(NextState.NO_MORE_VALUES).hasMoreValues();<a name="line.680"></a>
+<span class="sourceLineNo">681</span> }<a name="line.681"></a>
+<span class="sourceLineNo">682</span> matcher.clearCurrentRow();<a name="line.682"></a>
+<span class="sourceLineNo">683</span> seekOrSkipToNextRow(cell);<a name="line.683"></a>
+<span class="sourceLineNo">684</span> break;<a name="line.684"></a>
+<span class="sourceLineNo">685</span><a name="line.685"></a>
+<span class="sourceLineNo">686</span> case SEEK_NEXT_COL:<a name="line.686"></a>
+<span class="sourceLineNo">687</span> seekOrSkipToNextColumn(cell);<a name="line.687"></a>
+<span class="sourceLineNo">688</span> break;<a name="line.688"></a>
+<span class="sourceLineNo">689</span><a name="line.689"></a>
+<span class="sourceLineNo">690</span> case SKIP:<a name="line.690"></a>
+<span class="sourceLineNo">691</span> this.heap.next();<a name="line.691"></a>
+<span class="sourceLineNo">692</span> break;<a name="line.692"></a>
+<span class="sourceLineNo">693</span><a name="line.693"></a>
+<span class="sourceLineNo">694</span> case SEEK_NEXT_USING_HINT:<a name="line.694"></a>
+<span class="sourceLineNo">695</span> Cell nextKV = matcher.getNextKeyHint(cell);<a name="line.695"></a>
+<span class="sourceLineNo">696</span> if (nextKV != null) {<a name="line.696"></a>
+<span class="sourceLineNo">697</span> seekAsDirection(nextKV);<a name="line.697"></a>
+<span class="sourceLineNo">698</span> } else {<a name="line.698"></a>
+<span class="sourceLineNo">699</span> heap.next();<a name="line.699"></a>
+<span class="sourceLineNo">700</span> }<a name="line.700"></a>
+<span class="sourceLineNo">701</span> break;<a name="line.701"></a>
+<span class="sourceLineNo">702</span><a name="line.702"></a>
+<span class="sourceLineNo">703</span> default:<a name="line.703"></a>
+<span class="sourceLineNo">704</span> throw new RuntimeException("UNEXPECTED");<a name="line.704"></a>
+<span class="sourceLineNo">705</span> }<a name="line.705"></a>
+<span class="sourceLineNo">706</span> } while ((cell = this.heap.peek()) != null);<a name="line.706"></a>
+<span class="sourceLineNo">707</span><a name="line.707"></a>
+<span class="sourceLineNo">708</span> if (count > 0) {<a name="line.708"></a>
+<span class="sourceLineNo">709</span> return scannerContext.setScannerState(NextState.MORE_VALUES).hasMoreValues();<a name="line.709"></a>
+<span class="sourceLineNo">710</span> }<a name="line.710"></a>
+<span class="sourceLineNo">711</span><a name="line.711"></a>
+<span class="sourceLineNo">712</span> // No more keys<a name="line.712"></a>
+<span class="sourceLineNo">713</span> close(false);// Do all cleanup except heap.close()<a name="line.713"></a>
+<span class="sourceLineNo">714</span> return scannerContext.setScannerState(NextState.NO_MORE_VALUES).hasMoreValues();<a name="line.714"></a>
+<span class="sourceLineNo">715</span> }<a name="line.715"></a>
+<span class="sourceLineNo">716</span><a name="line.716"></a>
+<span class="sourceLineNo">717</span> private void seekOrSkipToNextRow(Cell cell) throws IOException {<a name="line.717"></a>
+<span class="sourceLineNo">718</span> // If it is a Get Scan, then we know that we are done with this row; there are no more<a name="line.718"></a>
+<span class="sourceLineNo">719</span> // rows beyond the current one: don't try to optimize.<a name="line.719"></a>
+<span class="sourceLineNo">720</span> if (!get) {<a name="line.720"></a>
+<span class="sourceLineNo">721</span> if (trySkipToNextRow(cell)) {<a name="line.721"></a>
+<span class="sourceLineNo">722</span> return;<a name="line.722"></a>
+<span class="sourceLineNo">723</span> }<a name="line.723"></a>
+<span class="sourceLineNo">724</span> }<a name="line.724"></a>
+<span class="sourceLineNo">725</span> seekToNextRow(cell);<a name="line.725"></a>
+<span class="sourceLineNo">726</span> }<a name="line.726"></a>
+<span class="sourceLineNo">727</span><a name="line.727"></a>
+<span class="sourceLineNo">728</span> private void seekOrSkipToNextColumn(Cell cell) throws IOException {<a name="line.728"></a>
+<span class="sourceLineNo">729</span> if (!trySkipToNextColumn(cell)) {<a name="line.729"></a>
+<span class="sourceLineNo">730</span> seekAsDirection(matcher.getKeyForNextColumn(cell));<a name="line.730"></a>
+<span class="sourceLineNo">731</span> }<a name="line.731"></a>
+<span class="sourceLineNo">732</span> }<a name="line.732"></a>
+<span class="sourceLineNo">733</span><a name="line.733"></a>
+<span class="sourceLineNo">734</span> /**<a name="line.734"></a>
+<span class="sourceLineNo">735</span> * See if we should actually SEEK or rather just SKIP to the next Cell (see HBASE-13109).<a name="line.735"></a>
+<span class="sourceLineNo">736</span> * ScanQueryMatcher may issue SEEK hints, such as seek to next column, next row,<a name="line.736"></a>
+<span class="sourceLineNo">737</span> * or seek to an arbitrary seek key. This method decides whether a seek is the most efficient<a name="line.737"></a>
+<span class="sourceLineNo">738</span> * _actual_ way to get us to the requested cell (SEEKs are more expensive than SKIP, SKIP,<a name="line.738"></a>
+<span class="sourceLineNo">739</span> * SKIP inside the current, loaded block).<a name="line.739"></a>
+<span class="sourceLineNo">740</span> * It does this by looking at the next indexed key of the current HFile. This key<a name="line.740"></a>
+<span class="sourceLineNo">741</span> * is then compared with the _SEEK_ key, where a SEEK key is an artificial 'last possible key<a name="line.741"></a>
+<span class="sourceLineNo">742</span> * on the row' (only in here, we avoid actually creating a SEEK key; in the compare we work with<a name="line.742"></a>
+<span class="sourceLineNo">743</span> * the current Cell but compare as though it were a seek key; see down in<a name="line.743"></a>
+<span class="sourceLineNo">744</span> * matcher.compareKeyForNextRow, etc). If the compare gets us onto the<a name="line.744"></a>
+<span class="sourceLineNo">745</span> * next block we *_SEEK, otherwise we just SKIP to the next requested cell.<a name="line.745"></a>
+<span class="sourceLineNo">746</span> *<a name="line.746"></a>
+<span class="sourceLineNo">747</span> * <p>Other notes:<a name="line.747"></a>
+<span class="sourceLineNo">748</span> * <ul><a name="line.748"></a>
+<span class="sourceLineNo">749</span> * <li>Rows can straddle block boundaries</li><a name="line.749"></a>
+<span class="sourceLineNo">750</span> * <li>Versions of columns can straddle block boundaries (i.e. column C1 at T1 might be in a<a name="line.750"></a>
+<span class="sourceLineNo">751</span> * different block than column C1 at T2)</li><a name="line.751"></a>
+<span class="sourceLineNo">752</span> * <li>We want to SKIP if the chance is high that we'll find the desired Cell after a<a name="line.752"></a>
+<span class="sourceLineNo">753</span> * few SKIPs...</li><a name="line.753"></a>
+<span class="sourceLineNo">754</span> * <li>We want to SEEK when the chance is high that we'll be able to seek<a name="line.754"></a>
+<span class="sourceLineNo">755</span> * past many Cells, especially if we know we need to go to the next block.</li><a name="line.755"></a>
+<span class="sourceLineNo">756</span> * </ul><a name="line.756"></a>
+<span class="sourceLineNo">757</span> * <p>A good proxy (best effort) to determine whether SKIP is better than SEEK is whether<a name="line.757"></a>
+<span class="sourceLineNo">758</span> * we'll likely end up seeking to the next block (or past the next block) to get our next column.<a name="line.758"></a>
+<span class="sourceLineNo">759</span> * Example:<a name="line.759"></a>
+<span class="sourceLineNo">760</span> * <pre><a name="line.760"></a>
+<span class="sourceLineNo">761</span> * | BLOCK 1 | BLOCK 2 |<a name="line.761"></a>
+<span class="sourceLineNo">762</span> * | r1/c1, r1/c2, r1/c3 | r1/c4, r1/c5, r2/c1 |<a name="line.762"></a>
+<span class="sourceLineNo">763</span> * ^ ^<a name="line.763"></a>
+<span class="sourceLineNo">764</span> * | |<a name="line.764"></a>
+<span class="sourceLineNo">765</span> * Next Index Key SEEK_NEXT_ROW (before r2/c1)<a name="line.765"></a>
+<span class="sourceLineNo">766</span> *<a name="line.766"></a>
<span class="sourceLineNo">767</span> *<a name="line.767"></a>
-<span class="sourceLineNo">768</span> *<a name="line.768"></a>
-<span class="sourceLineNo">769</span> * | BLOCK 1 | BLOCK 2 |<a name="line.769"></a>
-<span class="sourceLineNo">770</span> * | r1/c1/t5, r1/c1/t4, r1/c1/t3 | r1/c1/t2, r1/c1/T1, r1/c2/T3 |<a name="line.770"></a>
-<span class="sourceLineNo">771</span> * ^ ^<a name="line.771"></a>
-<span class="sourceLineNo">772</span> * | |<a name="line.772"></a>
-<span class="sourceLineNo">773</span> * Next Index Key SEEK_NEXT_COL<a name="line.773"></a>
-<span class="sourceLineNo">774</span> * </pre><a name="line.774"></a>
-<span class="sourceLineNo">775</span> * Now imagine we want columns c1 and c3 (see first diagram above), the 'Next Index Key' of r1/c4<a name="line.775"></a>
-<span class="sourceLineNo">776</span> * is > r1/c3 so we should seek to get to the c1 on the next row, r2. In second case, say we only<a name="line.776"></a>
-<span class="sourceLineNo">777</span> * want one version of c1, after we have it, a SEEK_COL will be issued to get to c2. Looking at<a name="line.777"></a>
-<span class="sourceLineNo">778</span> * the 'Next Index Key', it would land us in the next block, so we should SEEK. In other scenarios<a name="line.778"></a>
-<span class="sourceLineNo">779</span> * where the SEEK will not land us in the next block, it is very likely better to issues a series<a name="line.779"></a>
-<span class="sourceLineNo">780</span> * of SKIPs.<a name="line.780"></a>
-<span class="sourceLineNo">781</span> * @param cell current cell<a name="line.781"></a>
-<span class="sourceLineNo">782</span> * @return true means skip to next row, false means not<a name="line.782"></a>
-<span class="sourceLineNo">783</span> */<a name="line.783"></a>
-<span class="sourceLineNo">784</span> @VisibleForTesting<a name="line.784"></a>
-<span class="sourceLineNo">785</span> protected boolean trySkipToNextRow(Cell cell) throws IOException {<a name="line.785"></a>
-<span class="sourceLineNo">786</span> Cell nextCell = null;<a name="line.786"></a>
-<span class="sourceLineNo">787</span> do {<a name="line.787"></a>
-<span class="sourceLineNo">788</span> Cell nextIndexedKey = getNextIndexedKey();<a name="line.788"></a>
-<span class="sourceLineNo">789</span> if (nextIndexedKey != null && nextIndexedKey != KeyValueScanner.NO_NEXT_INDEXED_KEY<a name="line.789"></a>
-<span class="sourceLineNo">790</span> && matcher.compareKeyForNextRow(nextIndexedKey, cell) >= 0) {<a name="line.790"></a>
-<span class="sourceLineNo">791</span> this.heap.next();<a name="line.791"></a>
-<span class="sourceLineNo">792</span> ++kvsScanned;<a name="line.792"></a>
-<span class="sourceLineNo">793</span> } else {<a name="line.793"></a>
-<span class="sourceLineNo">794</span> return false;<a name="line.794"></a>
-<span class="sourceLineNo">795</span> }<a name="line.795"></a>
-<span class="sourceLineNo">796</span> } while ((nextCell = this.heap.peek()) != null && CellUtil.matchingRows(cell, nextCell));<a name="line.796"></a>
-<span class="sourceLineNo">797</span> return true;<a name="line.797"></a>
-<span class="sourceLineNo">798</span> }<a name="line.798"></a>
-<span class="sourceLineNo">799</span><a name="line.799"></a>
-<span class="sourceLineNo">800</span> /**<a name="line.800"></a>
-<span class="sourceLineNo">801</span> * See {@link org.apache.hadoop.hbase.regionserver.StoreScanner#trySkipToNextRow(Cell)}<a name="line.801"></a>
-<span class="sourceLineNo">802</span> * @param cell current cell<a name="line.802"></a>
-<span class="sourceLineNo">803</span> * @return true means skip to next column, false means not<a name="line.803"></a>
-<span class="sourceLineNo">804</span> */<a name="line.804"></a>
-<span class="sourceLineNo">805</span> @VisibleForTesting<a name="line.805"></a>
-<span class="sourceLineNo">806</span> protected boolean trySkipToNextColumn(Cell cell) throws IOException {<a name="line.806"></a>
-<span class="sourceLineNo">807</span> Cell nextCell = null;<a name="line.807"></a>
-<span class="sourceLineNo">808</span> do {<a name="line.808"></a>
-<span class="sourceLineNo">809</span> Cell nextIndexedKey = getNextIndexedKey();<a name="line.809"></a>
-<span class="sourceLineNo">810</span> if (nextIndexedKey != null && nextIndexedKey != KeyValueScanner.NO_NEXT_INDEXED_KEY<a name="line.810"></a>
-<span class="sourceLineNo">811</span> && matcher.compareKeyForNextColumn(nextIndexedKey, cell) >= 0) {<a name="line.811"></a>
-<span class="sourceLineNo">812</span> this.heap.next();<a name="line.812"></a>
-<span class="sourceLineNo">813</span> ++kvsScanned;<a name="line.813"></a>
-<span class="sourceLineNo">814</span> } else {<a name="line.814"></a>
-<span class="sourceLineNo">815</span> return false;<a name="line.815"></a>
-<span class="sourceLineNo">816</span> }<a name="line.816"></a>
-<span class="sourceLineNo">817</span> } while ((nextCell = this.heap.peek()) != null && CellUtil.matchingRowColumn(cell, nextCell));<a name="line.817"></a>
-<span class="sourceLineNo">818</span> return true;<a name="line.818"></a>
-<span class="sourceLineNo">819</span> }<a name="line.819"></a>
-<span class="sourceLineNo">820</span><a name="line.820"></a>
-<span class="sourceLineNo">821</span> @Override<a name="line.821"></a>
-<span class="sourceLineNo">822</span> public long getReadPoint() {<a name="line.822"></a>
-<span class="sourceLineNo">823</span> return this.readPt;<a name="line.823"></a>
-<span class="sourceLineNo">824</span> }<a name="line.824"></a>
-<span class="sourceLineNo">825</span><a name="line.825"></a>
-<span class="sourceLineNo">826</span> private static void clearAndClose(List<KeyValueScanner> scanners) {<a name="line.826"></a>
-<span class="sourceLineNo">827</span> for (KeyValueScanner s : scanners) {<a name="line.827"></a>
-<span class="sourceLineNo">828</span> s.close();<a name="line.828"></a>
-<span class="sourceLineNo">829</span> }<a name="line.829"></a>
-<span class="sourceLineNo">830</span> scanners.clear();<a name="line.830"></a>
-<span class="sourceLineNo">831</span> }<a name="line.831"></a>
-<span class="sourceLineNo">832</span><a name="line.832"></a>
-<span class="sourceLineNo">833</span> // Implementation of ChangedReadersObserver<a name="line.833"></a>
-<span class="sourceLineNo">834</span> @Override<a name="line.834"></a>
-<span class="sourceLineNo">835</span> public void updateReaders(List<StoreFile> sfs, List<KeyValueScanner> memStoreScanners) throws IOException {<a name="line.835"></a>
-<span class="sourceLineNo">836</span> if (CollectionUtils.isEmpty(sfs)<a name="line.836"></a>
-<span class="sourceLineNo">837</span> && CollectionUtils.isEmpty(memStoreScanners)) {<a name="line.837"></a>
-<span class="sourceLineNo">838</span> return;<a name="line.838"></a>
-<span class="sourceLineNo">839</span> }<a name="line.839"></a>
-<span class="sourceLineNo">840</span> flushLock.lock();<a name="line.840"></a>
-<span class="sourceLineNo">841</span> try {<a name="line.841"></a>
-<span class="sourceLineNo">842</span> flushed = true;<a name="line.842"></a>
-<span class="sourceLineNo">843</span> flushedStoreFiles.addAll(sfs);<a name="line.843"></a>
-<span class="sourceLineNo">844</span> if (!CollectionUtils.isEmpty(memStoreScanners)) {<a name="line.844"></a>
-<span class="sourceLineNo">845</span> clearAndClose(memStoreScannersAfterFlush);<a name="line.845"></a>
-<span class="sourceLineNo">846</span> memStoreScannersAfterFlush.addAll(memStoreScanners);<a name="line.846"></a>
-<span class="sourceLineNo">847</span> }<a name="line.847"></a>
-<span class="sourceLineNo">848</span> } finally {<a name="line.848"></a>
-<span class="sourceLineNo">849</span> flushLock.unlock();<a name="line.849"></a>
-<span class="sourceLineNo">850</span> }<a name="line.850"></a>
-<span class="sourceLineNo">851</span> // Let the next() call handle re-creating and seeking<a name="line.851"></a>
-<span class="sourceLineNo">852</span> }<a name="line.852"></a>
-<span class="sourceLineNo">853</span><a name="line.853"></a>
-<span class="sourceLineNo">854</span> /**<a name="line.854"></a>
-<span class="sourceLineNo">855</span> * @return if top of heap has changed (and KeyValueHeap has to try the next KV)<a name="line.855"></a>
-<span class="sourceLineNo">856</span> */<a name="line.856"></a>
-<span class="sourceLineNo">857</span> protected final boolean reopenAfterFlush() throws IOException {<a name="line.857"></a>
-<span class="sourceLineNo">858</span> Cell lastTop = heap.peek();<a name="line.858"></a>
-<span class="sourceLineNo">859</span> // When we have the scan object, should we not pass it to getScanners() to get a limited set of<a name="line.859"></a>
-<span class="sourceLineNo">860</span> // scanners? We did so in the constructor and we could have done it now by storing the scan<a name="line.860"></a>
-<span class="sourceLineNo">861</span> // object from the constructor<a name="line.861"></a>
-<span class="sourceLineNo">862</span> List<KeyValueScanner> scanners;<a name="line.862"></a>
-<span class="sourceLineNo">863</span> flushLock.lock();<a name="line.863"></a>
-<span class="sourceLineNo">864</span> try {<a name="line.864"></a>
-<span class="sourceLineNo">865</span> List<KeyValueScanner> allScanners = new ArrayList<>(flushedStoreFiles.size() + memStoreScannersAfterFlush.size());<a name="line.865"></a>
-<span class="sourceLineNo">866</span> allScanners.addAll(store.getScanners(flushedStoreFiles, cacheBlocks, get,<a name="line.866"></a>
-<span class="sourceLineNo">867</span> scanUsePread, false, matcher, scan.getStartRow(), scan.getStopRow(), this.readPt, false));<a name="line.867"></a>
-<span class="sourceLineNo">868</span> allScanners.addAll(memStoreScannersAfterFlush);<a name="line.868"></a>
-<span class="sourceLineNo">869</span> scanners = selectScannersFrom(allScanners);<a name="line.869"></a>
-<span class="sourceLineNo">870</span> // Clear the current set of flushed store files so that they don't get added again<a name="line.870"></a>
-<span class="sourceLineNo">871</span> flushedStoreFiles.clear();<a name="line.871"></a>
-<span class="sourceLineNo">872</span> memStoreScannersAfterFlush.clear();<a name="line.872"></a>
-<span class="sourceLineNo">873</span> } finally {<a name="line.873"></a>
-<span class="sourceLineNo">874</span> flushLock.unlock();<a name="line.874"></a>
-<span class="sourceLineNo">875</span> }<a name="line.875"></a>
-<span class="sourceLineNo">876</span><a name="line.876"></a>
-<span class="sourceLineNo">877</span> // Seek the new scanners to the last key<a name="line.877"></a>
-<span class="sourceLineNo">878</span> seekScanners(scanners, lastTop, false, parallelSeekEnabled);<a name="line.878"></a>
-<span class="sourceLineNo">879</span> // remove the older memstore scanner<a name="line.879"></a>
-<span class="sourceLineNo">880</span> for (int i = 0; i < currentScanners.size(); i++) {<a name="line.880"></a>
-<span class="sourceLineNo">881</span> if (!currentScanners.get(i).isFileScanner()) {<a name="line.881"></a>
-<span class="sourceLineNo">882</span> currentScanners.remove(i).close();<a name="line.882"></a>
-<span class="sourceLineNo">883</span> break;<a name="line.883"></a>
-<span class="sourceLineNo">884</span> }<a name="line.884"></a>
-<span class="sourceLineNo">885</span> }<a name="line.885"></a>
-<span class="sourceLineNo">886</span> // add the newly created scanners on the flushed files and the current active memstore scanner<a name="line.886"></a>
-<span class="sourceLineNo">887</span> addCurrentScanners(scanners);<a name="line.887"></a>
-<span class="sourceLineNo">888</span> // Combine all seeked scanners with a heap<a name="line.888"></a>
-<span class="sourceLineNo">889</span> resetKVHeap(this.currentScanners, store.getComparator());<a name="line.889"></a>
-<span class="sourceLineNo">890</span> resetQueryMatcher(lastTop);<a name="line.890"></a>
-<span class="sourceLineNo">891</span> if (heap.peek() == null || store.getComparator().compareRows(lastTop, this.heap.peek()) != 0) {<a name="line.891"></a>
-<span class="sourceLineNo">892</span> if (LOG.isDebugEnabled()) {<a name="line.892"></a>
-<span class="sourceLineNo">893</span> LOG.debug("Storescanner.peek() is changed where before = " + lastTop.toString() +<a name="line.893"></a>
-<span class="sourceLineNo">894</span> ",and after = " + heap.peek());<a name="line.894"></a>
-<span class="sourceLineNo">895</span> }<a name="line.895"></a>
-<span class="sourceLineNo">896</span> return true;<a name="line.896"></a>
-<span class="sourceLineNo">897</span> }<a name="line.897"></a>
-<span class="sourceLineNo">898</span> return false;<a name="line.898"></a>
-<span class="sourceLineNo">899</span> }<a name="line.899"></a>
-<span class="sourceLineNo">900</span><a name="line.900"></a>
-<span class="sourceLineNo">901</span> private void resetQueryMatcher(Cell lastTopKey) {<a name="line.901"></a>
-<span class="sourceLineNo">902</span> // Reset the state of the Query Matcher and set to top row.<a name="line.902"></a>
-<span class="sourceLineNo">903</span> // Only reset and call setRow if the row changes; avoids confusing the<a name="line.903"></a>
-<span class="sourceLineNo">904</span> // query matcher if scanning intra-row.<a name="line.904"></a>
-<span class="sourceLineNo">905</span> Cell cell = heap.peek();<a name="line.905"></a>
-<span class="sourceLineNo">906</span> if (cell == null) {<a name="line.906"></a>
-<span class="sourceLineNo">907</span> cell = lastTopKey;<a name="line.907"></a>
-<span class="sourceLineNo">908</span> }<a name="line.908"></a>
-<span class="sourceLineNo">909</span> if ((matcher.currentRow() == null) || !CellUtil.matchingRows(cell, matcher.currentRow())) {<a name="line.909"></a>
-<span class="sourceLineNo">910</span> this.countPerRow = 0;<a name="line.910"></a>
-<span class="sourceLineNo">911</span> // The setToNewRow will call reset internally<a name="line.911"></a>
-<span class="sourceLineNo">912</span> matcher.setToNewRow(cell);<a name="line.912"></a>
-<span class="sourceLineNo">913</span> }<a name="line.913"></a>
-<span class="sourceLineNo">914</span> }<a name="line.914"></a>
-<span class="sourceLineNo">915</span><a name="line.915"></a>
-<span class="sourceLineNo">916</span> /**<a name="line.916"></a>
-<span class="sourceLineNo">917</span> * Check whether scan as expected order<a name="line.917"></a>
-<span class="sourceLineNo">918</span> * @param prevKV<a name="line.918"></a>
-<span class="sourceLineNo">919</span> * @param kv<a name="line.919"></a>
-<span class="sourceLineNo">920</span> * @param comparator<a name="line.920"></a>
-<span class="sourceLineNo">921</span> * @throws IOException<a name="line.921"></a>
-<span class="sourceLineNo">922</span> */<a name="line.922"></a>
-<span class="sourceLineNo">923</span> protected void checkScanOrder(Cell prevKV, Cell kv,<a name="line.923"></a>
-<span class="sourceLineNo">924</span> CellComparator comparator) throws IOException {<a name="line.924"></a>
-<span class="sourceLineNo">925</span> // Check that the heap gives us KVs in an increasing order.<a name="line.925"></a>
-<span class="sourceLineNo">926</span> assert prevKV == null || comparator == null<a name="line.926"></a>
-<span class="sourceLineNo">927</span> || comparator.compare(prevKV, kv) <= 0 : "Key " + prevKV<a name="line.927"></a>
-<span class="sourceLineNo">928</span> + " followed by a " + "smaller key " + kv + " in cf " + store;<a name="line.928"></a>
-<span class="sourceLineNo">929</span> }<a name="line.929"></a>
-<span class="sourceLineNo">930</span><a name="line.930"></a>
-<span class="sourceLineNo">931</span> protected boolean seekToNextRow(Cell c) throws IOException {<a name="line.931"></a>
-<span class="sourceLineNo">932</span> return reseek(CellUtil.createLastOnRow(c));<a name="line.932"></a>
-<span class="sourceLineNo">933</span> }<a name="line.933"></a>
-<span class="sourceLineNo">934</span><a name="line.934"></a>
-<span class="sourceLineNo">935</span> /**<a name="line.935"></a>
-<span class="sourceLineNo">936</span> * Do a reseek in a normal StoreScanner(scan forward)<a name="line.936"></a>
-<span class="sourceLineNo">937</span> * @param kv<a name="line.937"></a>
-<span class="sourceLineNo">938</span> * @return true if scanner has values left, false if end of scanner<a name="line.938"></a>
-<span class="sourceLineNo">939</span> * @throws IOException<a name="line.939"></a>
-<span class="sourceLineNo">940</span> */<a name="line.940"></a>
-<span class="sourceLineNo">941</span> protected boolean seekAsDirection(Cell kv)<a name="line.941"></a>
-<span class="sourceLineNo">942</span> throws IOException {<a name="line.942"></a>
-<span class="sourceLineNo">943</span> return reseek(kv);<a name="line.943"></a>
-<span class="sourceLineNo">944</span> }<a name="line.944"></a>
-<span class="sourceLineNo">945</span><a name="line.945"></a>
-<span class="sourceLineNo">946</span> @Override<a name="line.946"></a>
-<span class="sourceLineNo">947</span> public boolean reseek(Cell kv) throws IOException {<a name="line.947"></a>
-<span class="sourceLineNo">948</span> if (checkFlushed()) {<a name="line.948"></a>
-<span class="sourceLineNo">949</span> reopenAfterFlush();<a name="line.949"></a>
-<span class="sourceLineNo">950</span> }<a name="line.950"></a>
-<span class="sourceLineNo">951</span> if (explicitColumnQuery && lazySeekEnabledGlobally) {<a name="line.951"></a>
-<span class="sourceLineNo">952</span> return heap.requestSeek(kv, true, useRowColBloom);<a name="line.952"></a>
-<span class="sourceLineNo">953</span> }<a name="line.953"></a>
-<span class="sourceLineNo">954</span> return heap.reseek(kv);<a name="line.954"></a>
-<span class="sourceLineNo">955</span> }<a name="line.955"></a>
-<span class="sourceLineNo">956</span><a name="line.956"></a>
-<span class="sourceLineNo">957</span> private void trySwitchToStreamRead() throws IOException {<a name="line.957"></a>
-<span class="sourceLineNo">958</span> if (readType != Scan.ReadType.DEFAULT || !scanUsePread || closing || heap.peek() == null ||<a name="line.958"></a>
-<span class="sourceLineNo">959</span> bytesRead < preadMaxBytes) {<a name="line.959"></a>
-<span class="sourceLineNo">960</span> return;<a name="line.960"></a>
-<span class="sourceLineNo">961</span> }<a name="line.961"></a>
-<span class="sourceLineNo">962</span> if (LOG.isDebugEnabled()) {<a name="line.962"></a>
-<span class="sourceLineNo">963</span> LOG.debug("Switch to stream read because we have already read " + bytesRead +<a name="line.963"></a>
-<span class="sourceLineNo">964</span> " bytes from this scanner");<a name="line.964"></a>
-<span class="sourceLineNo">965</span> }<a name="line.965"></a>
-<span class="sourceLineNo">966</span> scanUsePread = false;<a name="line.966"></a>
-<span class="sourceLineNo">967</span> Cell lastTop = heap.peek();<a name="line.967"></a>
-<span class="sourceLineNo">968</span> Map<String, StoreFile> name2File = new HashMap<>(store.getStorefilesCount());<a name="line.968"></a>
-<span class="sourceLineNo">969</span> for (StoreFile file : store.getStorefiles()) {<a name="line.969"></a>
-<span class="sourceLineNo">970</span> name2File.put(file.getFileInfo().getActiveFileName(), file);<a name="line.970"></a>
-<span class="sourceLineNo">971</span> }<a name="line.971"></a>
-<span class="sourceLineNo">972</span> List<StoreFile> filesToReopen = new ArrayList<>();<a name="line.972"></a>
-<span class="sourceLineNo">973</span> List<KeyValueScanner> memstoreScanners = new ArrayList<>();<a name="line.973"></a>
-<span class="sourceLineNo">974</span> List<KeyValueScanner> fileScanners = null;<a name="line.974"></a>
-<span class="sourceLineNo">975</span> List<KeyValueScanner> scannersToClose = new ArrayList<>();<a name="line.975"></a>
-<span class="sourceLineNo">976</span> boolean succ = false;<a name="line.976"></a>
-<span class="sourceLineNo">977</span> try {<a name="line.977"></a>
-<span class="sourceLineNo">978</span> for (KeyValueScanner kvs : currentScanners) {<a name="line.978"></a>
-<span class="sourceLineNo">979</span> if (!kvs.isFileScanner()) {<a name="line.979"></a>
-<span class="sourceLineNo">980</span> memstoreScanners.add(kvs);<a name="line.980"></a>
-<span class="sourceLineNo">981</span> } else {<a name="line.981"></a>
-<span class="sourceLineNo">982</span> scannersToClose.add(kvs);<a name="line.982"></a>
-<span class="sourceLineNo">983</span> if (kvs.peek() == null) {<a name="line.983"></a>
-<span class="sourceLineNo">984</span> continue;<a name="line.984"></a>
-<span class="sourceLineNo">985</span> }<a name="line.985"></a>
-<span class="sourceLineNo">986</span> filesToReopen.add(name2File.get(kvs.getFilePath().getName()));<a name="line.986"></a>
-<span class="sourceLineNo">987</span> }<a name="line.987"></a>
-<span class="sourceLineNo">988</span> }<a name="line.988"></a>
-<span class="sourceLineNo">989</span> if (filesToReopen.isEmpty()) {<a name="line.989"></a>
-<span class="sourceLineNo">990</span> return;<a name="line.990"></a>
-<span class="sourceLineNo">991</span> }<a name="line.991"></a>
+<span class="sourceLineNo">768</span> * | BLOCK 1 | BLOCK 2 |<a name="line.768"></a>
+<span class="sourceLineNo">769</span> * | r1/c1/t5, r1/c1/t4, r1/c1/t3 | r1/c1/t2, r1/c1/T1, r1/c2/T3 |<a name="line.769"></a>
+<span class="sourceLineNo">770</span> * ^ ^<a name="line.770"></a>
+<span class="sourceLineNo">771</span> * | |<a name="line.771"></a>
+<span class="sourceLineNo">772</span> * Next Index Key SEEK_NEXT_COL<a name="line.772"></a>
+<span class="sourceLineNo">773</span> * </pre><a name="line.773"></a>
+<span class="sourceLineNo">774</span> * Now imagine we want columns c1 and c3 (see first diagram above), the 'Next Index Key' of r1/c4<a name="line.774"></a>
+<span class="sourceLineNo">775</span> * is > r1/c3 so we should seek to get to the c1 on the next row, r2. In second case, say we only<a name="line.775"></a>
+<span class="sourceLineNo">776</span> * want one version of c1, after we have it, a SEEK_COL will be issued to get to c2. Looking at<a name="line.776"></a>
+<span class="sourceLineNo">777</span> * the 'Next Index Key', it would land us in the next block, so we should SEEK. In other scenarios<a name="line.777"></a>
+<span class="sourceLineNo">778</span> * where the SEEK will not land us in the next block, it is very likely better to issues a series<a name="line.778"></a>
+<span class="sourceLineNo">779</span> * of SKIPs.<a name="line.779"></a>
+<span class="sourceLineNo">780</span> * @param cell current cell<a name="line.780"></a>
+<span class="sourceLineNo">781</span> * @return true means skip to next row, false means not<a name="line.781"></a>
+<span class="sourceLineNo">782</span> */<a name="line.782"></a>
+<span class="sourceLineNo">783</span> @VisibleForTesting<a name="line.783"></a>
+<span class="sourceLineNo">784</span> protected boolean trySkipToNextRow(Cell cell) throws IOException {<a name="line.784"></a>
+<span class="sourceLineNo">785</span> Cell nextCell = null;<a name="line.785"></a>
+<span class="sourceLineNo">786</span> do {<a name="line.786"></a>
+<span class="sourceLineNo">787</span> Cell nextIndexedKey = getNextIndexedKey();<a name="line.787"></a>
+<span class="sourceLineNo">788</span> if (nextIndexedKey != null && nextIndexedKey != KeyValueScanner.NO_NEXT_INDEXED_KEY<a name="line.788"></a>
+<span class="sourceLineNo">789</span> && matcher.compareKeyForNextRow(nextIndexedKey, cell) >= 0) {<a name="line.789"></a>
+<span class="sourceLineNo">790</span> this.heap.next();<a name="line.790"></a>
+<span class="sourceLineNo">791</span> ++kvsScanned;<a name="line.791"></a>
+<span class="sourceLineNo">792</span> } else {<a name="line.792"></a>
+<span class="sourceLineNo">793</span> return false;<a name="line.793"></a>
+<span class="sourceLineNo">794</span> }<a name="line.794"></a>
+<span class="sourceLineNo">795</span> } while ((nextCell = this.heap.peek()) != null && CellUtil.matchingRows(cell, nextCell));<a name="line.795"></a>
+<span class="sourceLineNo">796</span> return true;<a name="line.796"></a>
+<span class="sourceLineNo">797</span> }<a name="line.797"></a>
+<span class="sourceLineNo">798</span><a name="line.798"></a>
+<span class="sourceLineNo">799</span> /**<a name="line.799"></a>
+<span class="sourceLineNo">800</span> * See {@link org.apache.hadoop.hbase.regionserver.StoreScanner#trySkipToNextRow(Cell)}<a name="line.800"></a>
+<span class="sourceLineNo">801</span> * @param cell current cell<a name="line.801"></a>
+<span class="sourceLineNo">802</span> * @return true means skip to next column, false means not<a name="line.802"></a>
+<span class="sourceLineNo">803</span> */<a name="line.803"></a>
+<span class="sourceLineNo">804</span> @VisibleForTesting<a name="line.804"></a>
+<span class="sourceLineNo">805</span> protected boolean trySkipToNextColumn(Cell cell) throws IOException {<a name="line.805"></a>
+<span class="sourceLineNo">806</span> Cell nextCell = null;<a name="line.806"></a>
+<span class="sourceLineNo">807</span> do {<a name="line.807"></a>
+<span class="sourceLineNo">808</span> Cell nextIndexedKey = getNextIndexedKey();<a name="line.808"></a>
+<span class="sourceLineNo">809</span> if (nextIndexedKey != null && nextIndexedKey != KeyValueScanner.NO_NEXT_INDEXED_KEY<a name="line.809"></a>
+<span class="sourceLineNo">810</span> && matcher.compareKeyForNextColumn(nextIndexedKey, cell) >= 0) {<a name="line.810"></a>
+<span class="sourceLineNo">811</span> this.heap.next();<a name="line.811"></a>
+<span class="sourceLineNo">812</span> ++kvsScanned;<a name="line.812"></a>
+<span class="sourceLineNo">813</span> } else {<a name="line.813"></a>
+<span class="sourceLineNo">814</span> return false;<a name="line.814"></a>
+<span class="sourceLineNo">815</span> }<a name="line.815"></a>
+<span class="sourceLineNo">816</span> } while ((nextCell = this.heap.peek()) != null && CellUtil.matchingRowColumn(cell, nextCell));<a name="line.816"></a>
+<span class="sourceLineNo">817</span> return true;<a name="line.817"></a>
+<span class="sourceLineNo">818</span> }<a name="line.818"></a>
+<span class="sourceLineNo">819</span><a name="line.819"></a>
+<span class="sourceLineNo">820</span> @Override<a name="line.820"></a>
+<span class="sourceLineNo">821</span> public long getReadPoint() {<a name="line.821"></a>
+<span class="sourceLineNo">822</span> return this.readPt;<a name="line.822"></a>
+<span class="sourceLineNo">823</span> }<a name="line.823"></a>
+<span class="sourceLineNo">824</span><a name="line.824"></a>
+<span class="sourceLineNo">825</span> private static void clearAndClose(List<KeyValueScanner> scanners) {<a name="line.825"></a>
+<span class="sourceLineNo">826</span> for (KeyValueScanner s : scanners) {<a name="line.826"></a>
+<span class="sourceLineNo">827</span> s.close();<a name="line.827"></a>
+<span class="sourceLineNo">828</span> }<a name="line.828"></a>
+<span class="sourceLineNo">829</span> scanners.clear();<a name="line.829"></a>
+<span class="sourceLineNo">830</span> }<a name="line.830"></a>
+<span class="sourceLineNo">831</span><a name="line.831"></a>
+<span class="sourceLineNo">832</span> // Implementation of ChangedReadersObserver<a name="line.832"></a>
+<span class="sourceLineNo">833</span> @Override<a name="line.833"></a>
+<span class="sourceLineNo">834</span> public void updateReaders(List<StoreFile> sfs, List<KeyValueScanner> memStoreScanners) throws IOException {<a name="line.834"></a>
+<span class="sourceLineNo">835</span> if (CollectionUtils.isEmpty(sfs)<a name="line.835"></a>
+<span class="sourceLineNo">836</span> && CollectionUtils.isEmpty(memStoreScanners)) {<a name="line.836"></a>
+<span class="sourceLineNo">837</span> return;<a name="line.837"></a>
+<span class="sourceLineNo">838</span> }<a name="line.838"></a>
+<span class="sourceLineNo">839</span> flushLock.lock();<a name="line.839"></a>
+<span class="sourceLineNo">840</span> try {<a name="line.840"></a>
+<span class="sourceLineNo">841</span> flushed = true;<a name="line.841"></a>
+<span class="sourceLineNo">842</span> flushedStoreFiles.addAll(sfs);<a name="line.842"></a>
+<span class="sourceLineNo">843</span> if (!CollectionUtils.isEmpty(memStoreScanners)) {<a name="line.843"></a>
+<span class="sourceLineNo">844</span> clearAndClose(memStoreScannersAfterFlush);<a name="line.844"></a>
+<span class="sourceLineNo">845</span> memStoreScannersAfterFlush.addAll(memStoreScanners);<a name="line.845"></a>
+<span class="sourceLineNo">846</span> }<a name="line.846"></a>
+<span class="sourceLineNo">847</span> } finally {<a name="line.847"></a>
+<span class="sourceLineNo">848</span> flushLock.unlock();<a name="line.848"></a>
+<span class="sourceLineNo">849</span> }<a name="line.849"></a>
+<span class="sourceLineNo">850</span> // Let the next() call handle re-creating and seeking<a name="line.850"></a>
+<span class="sourceLineNo">851</span> }<a name="line.851"></a>
+<span class="sourceLineNo">852</span><a name="line.852"></a>
+<span class="sourceLineNo">853</span> /**<a name="line.853"></a>
+<span class="sourceLineNo">854</span> * @return if top of heap has changed (and KeyValueHeap has to try the next KV)<a name="line.854"></a>
+<span class="sourceLineNo">855</span> */<a name="line.855"></a>
+<span class="sourceLineNo">856</span> protected final boolean reopenAfterFlush() throws IOException {<a name="line.856"></a>
+<span class="sourceLineNo">857</span> Cell lastTop = heap.peek();<a name="line.857"></a>
+<span class="sourceLineNo">858</span> // When we have the scan object, should we not pass it to getScanners() to get a limited set of<a name="line.858"></a>
+<span class="sourceLineNo">859</span> // scanners? We did so in the constructor and we could have done it now by storing the scan<a name="line.859"></a>
+<span class="sourceLineNo">860</span> // object from the constructor<a name="line.860"></a>
+<span class="sourceLineNo">861</span> List<KeyValueScanner> scanners;<a name="line.861"></a>
+<span class="sourceLineNo">862</span> flushLock.lock();<a name="line.862"></a>
+<span class="sourceLineNo">863</span> try {<a name="line.863"></a>
+<span class="sourceLineNo">864</span> List<KeyValueScanner> allScanners = new ArrayList<>(flushedStoreFiles.size() + memStoreScannersAfterFlush.size());<a name="line.864"></a>
+<span class="sourceLineNo">865</span> allScanners.addAll(store.getScanners(flushedStoreFiles, cacheBlocks, get,<a name="line.865"></a>
+<span class="sourceLineNo">866</span> scanUsePread, false, matcher, scan.getStartRow(), scan.getStopRow(), this.readPt, false));<a name="line.866"></a>
+<span class="sourceLineNo">867</span> allScanners.addAll(memStoreScannersAfterFlush);<a name="line.867"></a>
+<span class="sourceLineNo">868</span> scanners = selectScannersFrom(allScanners);<a name="line.868"></a>
+<span class="sourceLineNo">869</span> // Clear the current set of flushed store files so that they don't get added again<a name="line.869"></a>
+<span class="sourceLineNo">870</span> flushedStoreFiles.clear();<a name="line.870"></a>
+<span class="sourceLineNo">871</span> memStoreScannersAfterFlush.clear();<a name="line.871"></a>
+<span class="sourceLineNo">872</span> } finally {<a name="line.872"></a>
+<span class="sourceLineNo">873</span> flushLock.unlock();<a name="line.873"></a>
+<span class="sourceLineNo">874</span> }<a name="line.874"></a>
+<span class="sourceLineNo">875</span><a name="line.875"></a>
+<span class="sourceLineNo">876</span> // Seek the new scanners to the last key<a name="line.876"></a>
+<span class="sourceLineNo">877</span> seekScanners(scanners, lastTop, false, parallelSeekEnabled);<a name="line.877"></a>
+<span class="sourceLineNo">878</span> // remove the older memstore scanner<a name="line.878"></a>
+<span class="sourceLineNo">879</span> for (int i = 0; i < currentScanners.size(); i++) {<a name="line.879"></a>
+<span class="sourceLineNo">880</span> if (!currentScanners.get(i).isFileScanner()) {<a name="line.880"></a>
+<span class="sourceLineNo">881</span> currentScanners.remove(i).close();<a name="line.881"></a>
+<span class="sourceLineNo">882</span> break;<a name="line.882"></a>
+<span class="sourceLineNo">883</span> }<a name="line.883"></a>
+<span class="sourceLineNo">884</span> }<a name="line.884"></a>
+<span class="sourceLineNo">885</span> // add the newly created scanners on the flushed files and the current active memstore scanner<a name="line.885"></a>
+<span class="sourceLineNo">886</span> addCurrentScanners(scanners);<a name="line.886"></a>
+<span class="sourceLineNo">887</span> // Combine all seeked scanners with a heap<a name="line.887"></a>
+<span class="sourceLineNo">888</span> resetKVHeap(this.currentScanners, store.getComparator());<a name="line.888"></a>
+<span class="sourceLineNo">889</span> resetQueryMatcher(lastTop);<a name="line.889"></a>
+<span class="sourceLineNo">890</span> if (heap.peek() == null || store.getComparator().compareRows(lastTop, this.heap.peek()) != 0) {<a name="line.890"></a>
+<span class="sourceLineNo">891</span> if (LOG.isDebugEnabled()) {<a name="line.891"></a>
+<span class="sourceLineNo">892</span> LOG.debug("Storescanner.peek() is changed where before = " + lastTop.toString() +<a name="line.892"></a>
+<span class="sourceLineNo">893</span> ",and after = " + heap.peek());<a name="line.893"></a>
+<span class="sourceLineNo">894</span> }<a name="line.894"></a>
+<span class="sourceLineNo">895</span> return true;<a name="line.895"></a>
+<span class="sourceLineNo">896</span> }<a name="line.896"></a>
+<span class="sourceLineNo">897</span> return false;<a name="line.897"></a>
+<span class="sourceLineNo">898</span> }<a name="line.898"></a>
+<span class="sourceLineNo">899</span><a name="line.899"></a>
+<span class="sourceLineNo">900</span> private void resetQueryMatcher(Cell lastTopKey) {<a name="line.900"></a>
+<span class="sourceLineNo">901</span> // Reset the state of the Query Matcher and set to top row.<a name="line.901"></a>
+<span class="sourceLineNo">902</span> // Only reset and call setRow if the row changes; avoids confusing the<a name="line.902"></a>
+<span class="sourceLineNo">903</span> // query matcher if scanning intra-row.<a name="line.903"></a>
+<span class="sourceLineNo">904</span> Cell cell = heap.peek();<a name="line.904"></a>
+<span class="sourceLineNo">905</span> if (cell == null) {<a name="line.905"></a>
+<span class="sourceLineNo">906</span> cell = lastTopKey;<a name="line.906"></a>
+<span class="sourceLineNo">907</span> }<a name="line.907"></a>
+<span class="sourceLineNo">908</span> if ((matcher.currentRow() == null) || !CellUtil.matchingRows(cell, matcher.currentRow())) {<a name="line.908"></a>
+<span class="sourceLineNo">909</span> this.countPerRow = 0;<a name="line.909"></a>
+<span class="sourceLineNo">910</span> // The setToNewRow will call reset internally<a name="line.910"></a>
+<span class="sourceLineNo">911</span> matcher.setToNewRow(cell);<a name="line.911"></a>
+<span class="sourceLineNo">912</span> }<a name="line.912"></a>
+<span class="sourceLineNo">913</span> }<a name="line.913"></a>
+<span class="sourceLineNo">914</span><a name="line.914"></a>
+<span class="sourceLineNo">915</span> /**<a name="line.915"></a>
+<span class="sourceLineNo">916</span> * Check whether scan as expected order<a name="line.916"></a>
+<span class="sourceLineNo">917</span> * @param prevKV<a name="line.917"></a>
+<span class="sourceLineNo">918</span> * @param kv<a name="line.918"></a>
+<span class="sourceLineNo">919</span> * @param comparator<a name="line.919"></a>
+<span class="sourceLineNo">920</span> * @throws IOException<a name="line.920"></a>
+<span class="sourceLineNo">921</span> */<a name="line.921"></a>
+<span class="sourceLineNo">922</span> protected void checkScanOrder(Cell prevKV, Cell kv,<a name="line.922"></a>
+<span class="sourceLineNo">923</span> CellComparator comparator) throws IOException {<a name="line.923"></a>
+<span class="sourceLineNo">924</span> // Check that the heap gives us KVs in an increasing order.<a name="line.924"></a>
+<span class="sourceLineNo">925</span> assert prevKV == null || comparator == null<a name="line.925"></a>
+<span class="sourceLineNo">926</span> || comparator.compare(prevKV, kv) <= 0 : "Key " + prevKV<a name="line.926"></a>
+<span class="sourceLineNo">927</span> + " followed by a " + "smaller key " + kv + " in cf " + store;<a name="line.927"></a>
+<span class="sourceLineNo">928</span> }<a name="line.928"></a>
+<span class="sourceLineNo">929</span><a name="line.929"></a>
+<span class="sourceLineNo">930</span> protected boolean seekToNextRow(Cell c) throws IOException {<a name="line.930"></a>
+<span class="sourceLineNo">931</span> return reseek(CellUtil.createLastOnRow(c));<a name="line.931"></a>
+<span class="sourceLineNo">932</span> }<a name="line.932"></a>
+<span class="sourceLineNo">933</span><a name="line.933"></a>
+<span class="sourceLineNo">934</span> /**<a name="line.934"></a>
+<span class="sourceLineNo">935</span> * Do a reseek in a normal StoreScanner(scan forward)<a name="line.935"></a>
+<span class="sourceLineNo">936</span> * @param kv<a name="line.936"></a>
+<span class="sourceLineNo">937</span> * @return true if scanner has values left, false if end of scanner<a name="line.937"></a>
+<span class="sourceLineNo">938</span> * @throws IOException<a name="line.938"></a>
+<span class="sourceLineNo">939</span> */<a name="line.939"></a>
+<span class="sourceLineNo">940</span> protected boolean seekAsDirection(Cell kv)<a name="line.940"></a>
+<span class="sourceLineNo">941</span> throws IOException {<a name="line.941"></a>
+<span class="sourceLineNo">942</span> return reseek(kv);<a name="line.942"></a>
+<span class="sourceLineNo">943</span> }<a name="line.943"></a>
+<span class="sourceLineNo">944</span><a name="line.944"></a>
+<span class="sourceLineNo">945</span> @Override<a name="line.945"></a>
+<span class="sourceLineNo">946</span> public boolean reseek(Cell kv) throws IOException {<a name="line.946"></a>
+<span class="sourceLineNo">947</span> if (checkFlushed()) {<a name="line.947"></a>
+<span class="sourceLineNo">948</span> reopenAfterFlush();<a name="line.948"></a>
+<span class="sourceLineNo">949</span> }<a name="line.949"></a>
+<span class="sourceLineNo">950</span> if (explicitColumnQuery && lazySeekEnabledGlobally) {<a name="line.950"></a>
+<span class="sourceLineNo">951</span> return heap.requestSeek(kv, true, useRowColBloom);<a name="line.951"></a>
+<span class="sourceLineNo">952</span> }<a name="line.952"></a>
+<span class="sourceLineNo">953</span> return heap.reseek(kv);<a name="line.953"></a>
+<span class="sourceLineNo">954</span> }<a name="line.954"></a>
+<span class="sourceLineNo">955</span><a name="line.955"></a>
+<span class="sourceLineNo">956</span> private void trySwitchToStreamRead() {<a name="line.956"></a>
+<span class="sourceLineNo">957</span> if (readType != Scan.ReadType.DEFAULT || !scanUsePread || closing || heap.peek() == null ||<a name="line.957"></a>
+<span class="sourceLineNo">958</span> bytesRead < preadMaxBytes) {<a name="line.958"></a>
+<span class="sourceLineNo">959</span> return;<a name="line.959"></a>
+<span class="sourceLineNo">960</span> }<a name="line.960"></a>
+<span class="sourceLineNo">961</span> if (LOG.isDebugEnabled()) {<a name="line.961"></a>
+<span class="sourceLineNo">962</span> LOG.debug("Switch to stream read because we have already read " + bytesRead +<a name="line.962"></a>
+<span class="sourceLineNo">963</span> " bytes from this scanner");<a name="line.963"></a>
+<span class="sourceLineNo">964</span> }<a name="line.964"></a>
+<span class="sourceLineNo">965</span> scanUsePread = false;<a name="line.965"></a>
+<span class="sourceLineNo">966</span> Cell lastTop = heap.peek();<a name="line.966"></a>
+<span class="sourceLineNo">967</sp
<TRUNCATED>