/**
* This method read the given number of tuples from disk to disk_buffer.
*
* @throws java.io.IOException
*/
public void readDiskTuplesIntoBufferB() throws java.io.IOException {
long startTime = 0, endTime = 0;
int row = 0;
startTime = System.nanoTime();
try {
startTime = System.nanoTime();
rs =
stmt.executeQuery(
"SELECT * from lookup_table_twomillion where attr1>="
+ startRead
+ " AND attr1<"
+ (startRead + DISK_BUFFER)
+ "");
endTime = System.nanoTime();
if (measurementStart) {
CIO[CIO_index++] = endTime - startTime;
}
while (rs.next()) {
for (int col = 1; col <= 30; col++) {
bufferB[row][col - 1] = rs.getInt(col);
}
row++;
}
} catch (SQLException e) {
System.out.print(e);
}
startRead += DISK_BUFFER;
}
/**
* This method remove the oldest tuples from hash table along with their addresses
*
* @param ht
*/
public void removeExpireTuples() {
long startTime = 0, endTime = 0, CE_per_Iteration = 0;
int w[] = (int[]) abq.poll();
for (int i = 0; i < STREAM_BUFFER; i++) {
startTime = System.nanoTime();
if (mhm.containsKey(new Integer(get(w, i)))) {
mhm.remove(new Integer(get(w, i)));
unmatched++;
}
endTime = System.nanoTime();
CE_per_Iteration += endTime - startTime;
}
CE[CE_index++] = CE_per_Iteration / DISK_BUFFER;
}
/**
* This method generate the input stream and load it into stream buffer. Before loading the stream
* tuples into hash table it check the status of queue if it is already full remove the oldest
* tuples from hash table along with their pointer addresses from Queue. Finally it loads the new
* scanned tuples into hash table with their pointer address in queue.
*
* @param ht
*/
public void inputStream() {
long startTime = 0, endTime = 0, CA_per_Iteration = 0;
;
int w[] = new int[STREAM_BUFFER];
if (round2) {
removeExpireTuples();
}
while (streamBuffer.size() < STREAM_BUFFER) ;
for (int i = 0; i < STREAM_BUFFER; i++) {
startTime = System.nanoTime();
set(w, streamBuffer.peek().attr1, i);
mhm.put(new Integer(streamBuffer.peek().attr1), streamBuffer.poll());
endTime = System.nanoTime();
if (measurementStart) {
CA_per_Iteration += endTime - startTime;
}
}
System.out.println("Available stream size After: " + streamBuffer.size());
abq.offer(w);
if (measurementStart) {
CA[CA_index++] = CA_per_Iteration / STREAM_BUFFER;
}
}
/**
* This method sequentially read the fixed amount of tuples from the disk using disk_buffer and
* probe them in hash table.
*
* @param ht
* @throws java.sql.SQLException
*/
public void lookupMasterData() throws java.io.IOException, InterruptedException {
long startTime = 0, endTime = 0, CH_per_Iteration = 0;
int matched = 0, diskInputs = 0;
conn = connectDB();
mhm.clear();
int index = 0;
try {
stmt = conn.createStatement();
stmt.setFetchSize(DISK_BUFFER);
} catch (SQLException exp) {
exp.printStackTrace();
}
stream.start();
// Thread.sleep(LATE_START);
for (int round = 1; round <= 2; round++) {
startRead = 1;
if (round == 2) {
System.out.println("Second round started");
round2 = true;
}
for (int tuple = 0; tuple < R_SIZE; tuple++) {
measurementStart = false;
if ((round2) && (tuple >= MEASUREMENT_START && tuple < MEASUREMENT_STOP)) {
measurementStart = true;
}
if (tuple % DISK_BUFFER == 0) {
readDiskTuplesIntoBufferB();
inputStream();
diskInputs++;
if (measurementStart && matched != 0) {
CH[CH_index++] = CH_per_Iteration / matched;
CH_per_Iteration = 0;
matched = 0;
}
index = 0;
}
if (mhm.containsKey(bufferB[index][0])) {
startTime = System.nanoTime();
list = (ArrayList<MeshJoinObject>) mhm.get(bufferB[index][0]);
endTime = System.nanoTime();
if (measurementStart) {
CH_per_Iteration += endTime - startTime;
matched++;
}
}
index++;
}
}
stream.stop();
closeConnection(conn);
System.out.println("Hash tuples: " + mhm.size());
System.out.println("Unmatched tuples: " + unmatched);
System.out.println("Iterations required to bring R into Disk_buffer=" + diskInputs);
System.out.println("Stream back log: " + streamBuffer.size());
}