wl2126 - ndb - batching of range scans

  between 80% and 360% performance improvement measured

ndb/docs/wl2077.txt

@@ -10,6 +10,10 @@ results in 1000 rows / sec
 wl2077-read committed			6.4 (+30%)	10.8 (+45%)
 wl2077-read hold lock			4.6 (-1%)	6.7 (+ 0%)
 
+5.0-ndb batch read committed		f) 50' (+680%)	g) 50' (+360%)
+5.0-ndb batch read hold lock		h) 12' (+160%)	i) 13' (+79%)
+
+
 -- Comparision e)
 serial pk:	       10.9'
 batched (1000):	       59'
@@ -25,6 +29,8 @@ b) testScanPerf -s 100000 -c 0 -d 0 -a 1 -l 0 -r 2 -q 1 T1
 c) testScanPerf -s 100000 -c 0 -d 0 -a 1 -l 1 -r 2 -q 0 T1
 d) testScanPerf -s 100000 -c 0 -d 0 -a 1 -l 1 -r 2 -q 1 T1
 e) testReadPerf -i 25 -c 0 -d 0 T1
+f) testScanPerf -s 100000 -c 0 -d 0 -a 1 -l 0 -r 3 -q 0 -m 1000 -i 10 T1
+g) testScanPerf -s 100000 -c 0 -d 0 -a 1 -l 0 -r 3 -q 1 -m 1000 -i 10 T1
 
 --- music join		1db-co		2db-co
 			
@@ -33,3 +39,5 @@ e) testReadPerf -i 25 -c 0 -d 0 T1
 
 wl2077			12s		14s
 wl2077 wo/ blobs	1.2s (-30%)	2.5s (-22%)
+
+pekka-blob-fix		1.3s

ndb/src/kernel/blocks/dblqh/DblqhMain.cpp

@@ -8110,7 +8110,10 @@ void Dblqh::nextScanConfScanLab(Signal* signal)
 
     if (scanptr.p->m_curr_batch_size_rows > 0) {
       jam();
+
+      if((tcConnectptr.p->primKeyLen - 4) == 0)
 	scanptr.p->scanCompletedStatus = ZTRUE;
+      
       scanptr.p->scanState = ScanRecord::WAIT_SCAN_NEXTREQ;
       sendScanFragConf(signal, ZFALSE);
       return;