Beispiel #1
0
// create pages 100 with content "Page X" and perform 10000 random reads of these pages and check that the correct pages are read
void
testCreatingAndRandomReadingDummyPages (void)
{
  int i;
  BM_BufferPool *bm = MAKE_POOL();
  testName = "Creating and Dummy Pages and reading them in random order";

  CHECK(createPageFile("testbuffer.bin"));
  createDummyPages(bm, 100);

  CHECK(initBufferPool(bm, "testbuffer.bin", 10, RS_FIFO, NULL));

  srand(time(0));
  for(i = 0; i < 10000; i++)
    {
      int page = rand() % NUM_DUMMY_PAGES;
      readAndCheckDummyPage(bm, page);
    }

  CHECK(shutdownBufferPool(bm));
  CHECK(destroyPageFile("testbuffer.bin"));

  free(bm);
  TEST_DONE();
}
void
testReadPage ()
{
  BM_BufferPool *bm = MAKE_POOL();
  BM_PageHandle *h = MAKE_PAGE_HANDLE();
  testName = "Reading a page";

  CHECK(createPageFile("testbuffer.bin"));
  CHECK(initBufferPool(bm, "testbuffer.bin", 3, RS_FIFO, NULL));
  
  CHECK(pinPage(bm, h, 0));
  CHECK(pinPage(bm, h, 0));

  CHECK(markDirty(bm, h));

  CHECK(unpinPage(bm,h));
  CHECK(unpinPage(bm,h));

  CHECK(forcePage(bm, h));

  CHECK(shutdownBufferPool(bm));
  CHECK(destroyPageFile("testbuffer.bin"));

  free(bm);
  free(h);

  TEST_DONE();
}
RC openTable (RM_TableData *rel, char *name){
    page=(BM_PageHandle *)calloc(PAGE_SIZE,sizeof(BM_PageHandle));
    Schema *schema;
    bm=MAKE_POOL();
    initBufferPool(bm,name, 3, RS_FIFO, NULL);
    pinPage(bm, page,0);
    schema=stringToSchema(page->data);
    rel->name=name;
    rel->schema=schema;
    rel->mgmtData=bm;
    return RC_OK;
}
void
testClock(void)
{
    // expected results
    const char *poolContents[]= {
        
    "[3x0],[-1 0],[-1 0],[-1 0]",
    "[3x0],[2 0],[-1 0],[-1 0]",
    "[3x0],[2 0],[0 0],[-1 0]",
    "[3x0],[2 0],[0 0],[8 0]",
    "[4 0],[2 0],[0 0],[8 0]",
    "[4 0],[2 0],[0 0],[8 0]",
    "[4 0],[2 0],[5 0],[8 0]",
    "[4 0],[2 0],[5 0],[0 0]",
    "[9 0],[2 0],[5 0],[0 0]",
    "[9 0],[8 0],[5 0],[0 0]",
    "[9 0],[8 0],[3x0],[0 0]",
    "[9 0],[8 0],[3x0],[2 0]"
    };
    const int orderRequests[]= {3,2,0,8,4,2,5,0,9,8,3,2};
        
    int i;
    int snapshot = 0;
    BM_BufferPool *bm = MAKE_POOL();
    BM_PageHandle *h = MAKE_PAGE_HANDLE();
    testName = "Testing CLOCK page replacement";

    CHECK(createPageFile("testbuffer.bin"));
    createDummyPages(bm, 100);
    CHECK(initBufferPool(bm, "testbuffer.bin", 4, RS_CLOCK, NULL));
    
    for (i=0;i<11;i++)
    {
        pinPage(bm,h,orderRequests[i]);
	if(orderRequests[i] == 3)
		markDirty(bm,h);
        unpinPage(bm,h);
        ASSERT_EQUALS_POOL(poolContents[snapshot++], bm, "check pool content using pages");
    }
    
    forceFlushPool(bm);
    // check number of write IOs
    ASSERT_EQUALS_INT(2, getNumWriteIO(bm), "check number of write I/Os");
    ASSERT_EQUALS_INT(10, getNumReadIO(bm), "check number of read I/Os");
    
    CHECK(shutdownBufferPool(bm));
    CHECK(destroyPageFile("testbuffer.bin"));
    
    free(bm);
    free(h);
    TEST_DONE();
}
Beispiel #5
0
/*
 * This function is used to Open a Created Table,
 * for any operation to be performed, the table has to be opened first
 * Also store the Schema related info by deserializing the schema,
 * in the Table Data
 */
RC openTable (RM_TableData *rel, char *name)
{
	//Record Management to store record attributes
	RM_RecordMgmt *rm_mgmt = (RM_RecordMgmt*)malloc(sizeof(RM_RecordMgmt));

	FILE *fptr;	//FILE pointer
	fptr = fopen(name, "r+");	//Open the PageFile (Table)

	//Get the total Number of Pages in the page File
	char* readHeader;
	readHeader = (char*)calloc(PAGE_SIZE,sizeof(char));

	fgets(readHeader,PAGE_SIZE,fptr);

	char* totalPage;
	totalPage = readHeader;
	totalPages = atoi(totalPage);	//convert to integer

	//Make a Buffer Pool
	rm_mgmt->bm = MAKE_POOL();

	//Make a Page Handle
	BM_PageHandle *page = MAKE_PAGE_HANDLE();

	//Initialize the BufferPool
	initBufferPool(rm_mgmt->bm,name,6,RS_FIFO,NULL);

	//Pin the Page = 0, which has the Schema Information
	pinPage(rm_mgmt->bm,page,0);

	//FreePages are stored in an array
	rm_mgmt->freePages = (int*)malloc(sizeof(int));
	rm_mgmt->freePages[0] = totalPages;

	//initialize the table data attributes

	//Deserialzing the Schema gives us the Relation information (i.e. Schema info)
	rel->schema = deserializeSchema(page->data);

	//store the name of the schema
	rel->name = name;

	//store the record management details
	rel->mgmtData = rm_mgmt;

	//Free the temp. memory allocations
	free(readHeader);
	free(page);

	return RC_OK;
}
// test error cases
void
testError (void)
{
    BM_BufferPool *bm = MAKE_POOL();
    BM_PageHandle *h = MAKE_PAGE_HANDLE();
    testName = "ERROR TEST";
    
    CHECK(createPageFile("testbuffer.bin"));
    
    // pinpage until buffer pool is full and then request additional page.
    CHECK(initBufferPool(bm, "testbuffer.bin", 3, RS_FIFO, NULL));
    CHECK(pinPage(bm, h, 0));
    CHECK(pinPage(bm, h, 1));
    CHECK(pinPage(bm, h, 2));
    
    ASSERT_ERROR(pinPage(bm, h, 3), "try to pin page when pool is full of pinned pages with fix-count > 0");
    
    CHECK(shutdownBufferPool(bm));
    
    // try to pin page with negative page number.
    CHECK(initBufferPool(bm, "testbuffer.bin", 3, RS_FIFO, NULL));
    ASSERT_ERROR(pinPage(bm, h, -10), "try to pin page with negative page number");
    CHECK(shutdownBufferPool(bm));
    
    
    // try to use uninitialized buffer pool
    ASSERT_ERROR(initBufferPool(bm, "unavailable.bin", 3, RS_FIFO, NULL), "try to init buffer pool for non existing page file");
    ASSERT_ERROR(shutdownBufferPool(bm), "shutdown buffer pool that is not open");
    ASSERT_ERROR(forceFlushPool(bm), "flush buffer pool that is not open");
    ASSERT_ERROR(pinPage(bm, h, 1), "pin page in buffer pool that is not open");
    
    
    // try to unpin, mark, or force page that is not in pool
    CHECK(initBufferPool(bm, "testbuffer.bin", 3, RS_FIFO, NULL));
    ASSERT_ERROR(unpinPage(bm, h), "Try to unpin a page which is not available in framelist.");
    ASSERT_ERROR(forcePage(bm, h), "Try to forceflush a page which is not available in framelist.");
    ASSERT_ERROR(markDirty(bm, h), "Try to markdirty a page which is not available in framelist.");  
    CHECK(shutdownBufferPool(bm));
    
    // done remove page file
    CHECK(destroyPageFile("testbuffer.bin"));
    
    free(bm);
    free(h);
    TEST_DONE();  
}
// create n pages with content "Page X" and read them back to check whether the content is right
void testCreatingAndReadingDummyPages(void) {
	BM_BufferPool *bm = MAKE_POOL();
	testName = "Creating and Reading Back Dummy Pages";

	CHECK(createPageFile("testbuffer.bin"));

	createDummyPages(bm, 22);
	checkDummyPages(bm, 20);

	createDummyPages(bm, 10000);
	checkDummyPages(bm, 10000);

	CHECK(destroyPageFile("testbuffer.bin"));

	free(bm);
	TEST_DONE()
	;
}
Beispiel #8
0
// test error cases
void
testError (void)
{
  int i;
  BM_BufferPool *bm = MAKE_POOL();
  BM_PageHandle *h = MAKE_PAGE_HANDLE();
  testName = "Testing LRU page replacement";

  CHECK(createPageFile("testbuffer.bin"));

  // pin until buffer pool is full and request additional page
  CHECK(initBufferPool(bm, "testbuffer.bin", 3, RS_FIFO, NULL));
  CHECK(pinPage(bm, h, 0));
  CHECK(pinPage(bm, h, 1));
  CHECK(pinPage(bm, h, 2));
  ASSERT_ERROR(pinPage(bm, h, 3), "try to pin page when pool is full of pinned pages");
  CHECK(shutdownBufferPool(bm));

  // try to ready page with negative page number
  CHECK(initBufferPool(bm, "testbuffer.bin", 3, RS_FIFO, NULL));
  ASSERT_ERROR(pinPage(bm, h, -1), "try to pin page with negative page number");
  CHECK(shutdownBufferPool(bm));

  // try to use uninitialized buffer pool  
  ASSERT_ERROR(shutdownBufferPool(bm), "shutdown buffer pool that is not open");
  ASSERT_ERROR(forceFlushPool(bm), "flush buffer pool that is not open");
  ASSERT_ERROR(pinPage(bm, h, 1), "pin page in buffer pool that is not open");
  ASSERT_ERROR(initBufferPool(bm, "xxx.bin", 3, RS_FIFO, NULL), "try to init buffer pool for non existing page file");

  // try to unpin, mark, or force page that is not in pool
  CHECK(initBufferPool(bm, "testbuffer.bin", 3, RS_FIFO, NULL));
  ASSERT_ERROR(unpinPage(bm, h), "unpin page not in buffer pool");  
  ASSERT_ERROR(forcePage(bm, h), "unpin page not in buffer pool");  
  ASSERT_ERROR(markDirty(bm, h), "mark page dirty that is not in buffer pool");  
  CHECK(shutdownBufferPool(bm));

  // done remove page file
  CHECK(destroyPageFile("testbuffer.bin"));

  free(bm);
  free(h);
  TEST_DONE();  
}
void
testsimpleFIFO ()
{
printf("FIFO Execution in new thread : \n " );
// expected results
  const char *poolContents[] = {
    "[0 0],[-1 0],[-1 0]" ,
    "[0 0],[1 0],[-1 0]",
    "[0 0],[1 0],[2 0]",
    "[3 0],[1 0],[2 0]"
  };
  const int requests[] = {0,1,2,3,4,4,5,6,0};
  const int numLinRequests = 4;

  int i;
  BM_BufferPool *bm = MAKE_POOL();
  BM_PageHandle *h = MAKE_PAGE_HANDLE();
  testName = "Testing FIFO page replacement";

  CHECK(createPageFile("testbuffer.bin"));

  createDummyPages(bm, 100);

  CHECK(initBufferPool(bm, "testbuffer.bin", 3, RS_FIFO, NULL));

  // reading some pages linearly with direct unpin and no modifications
  for(i = 0; i < numLinRequests; i++)
    {
      pinPage(bm, h, requests[i]);
      unpinPage(bm, h);
      ASSERT_EQUALS_POOL(poolContents[i], bm, "check pool content");
    }

  CHECK(shutdownBufferPool(bm));
  CHECK(destroyPageFile("testbuffer.bin"));

  free(bm);
  free(h);
  TEST_DONE();
}
Beispiel #10
0
RC openBtree (BTreeHandle **tree, char *idxId){

    DataType keyType;
    int rootPage;
    int nodeNum;
    int entryNum;
    int n;
    BM_BufferPool  *bufferPool = MAKE_POOL();
    SM_FileHandle *fHandle = (SM_FileHandle *)calloc(1, sizeof(SM_FileHandle));
 
    char * metadata = (char *)calloc(PAGE_SIZE, sizeof(char));

    openPageFile(idxId, fHandle);
    initBufferPool(bufferPool, idxId, 10, RS_LRU, NULL);

    readBlock(0, fHandle, metadata);

    memcpy(&rootPage, metadata,sizeof(int));
    memcpy(&nodeNum, metadata+sizeof(int),sizeof(int));
    memcpy(&entryNum, metadata+2*sizeof(int),sizeof(int));
    memcpy(&n, metadata+3*sizeof(int),sizeof(int));
    memcpy(&keyType, metadata + 4*sizeof(int),sizeof(DataType));

    *tree = (BTreeHandle *)calloc(1, sizeof(BTreeHandle));
    
    (*tree)->keyType = keyType;
    (*tree)->rootPage = rootPage;
    (*tree)->nodeNum = nodeNum;
    (*tree)->entryNum = entryNum;
    (*tree)->n = n;
    (*tree)->bufferPool = bufferPool;
    (*tree)->fileHandle = fHandle;
    (*tree)->idxId = idxId;

    free(metadata);

    return RC_OK;
}
// test the LRU page replacement strategy
void
testLRU (void)
{
  // expected results
  const char *poolContents[] = { 
    // read first five pages and directly unpin them
    "[0 0],[-1 0],[-1 0],[-1 0],[-1 0]" , 
    "[0 0],[1 0],[-1 0],[-1 0],[-1 0]", 
    "[0 0],[1 0],[2 0],[-1 0],[-1 0]",
    "[0 0],[1 0],[2 0],[3 0],[-1 0]",
    "[0 0],[1 0],[2 0],[3 0],[4 0]",
    // use some of the page to create a fixed LRU order without changing pool content
    "[0 0],[1 0],[2 0],[3 0],[4 0]",
    "[0 0],[1 0],[2 0],[3 0],[4 0]",
    "[0 0],[1 0],[2 0],[3 0],[4 0]",
    "[0 0],[1 0],[2 0],[3 0],[4 0]",
    "[0 0],[1 0],[2 0],[3 0],[4 0]",
    // check that pages get evicted in LRU order
    "[0 0],[1 0],[2 0],[5 0],[4 0]",
    "[0 0],[1 0],[2 0],[5 0],[6 0]",
    "[7 0],[1 0],[2 0],[5 0],[6 0]",
    "[7 0],[1 0],[8 0],[5 0],[6 0]",
    "[7 0],[9 0],[8 0],[5 0],[6 0]"
  };
  const int orderRequests[] = {3,4,0,2,1};
  const int numLRUOrderChange = 5;

  int i;
  int snapshot = 0;
  BM_BufferPool *bm = MAKE_POOL();
  BM_PageHandle *h = MAKE_PAGE_HANDLE();
  testName = "Testing LRU page replacement";

  CHECK(createPageFile("testbuffer.bin"));
  createDummyPages(bm, 100);
  CHECK(initBufferPool(bm, "testbuffer.bin", 5, RS_LRU, NULL));

  // reading first five pages linearly with direct unpin and no modifications
  for(i = 0; i < 5; i++)
  {
      pinPage(bm, h, i);
      unpinPage(bm, h);
      ASSERT_EQUALS_POOL(poolContents[snapshot++], bm, "check pool content reading in pages");
  }

  // read pages to change LRU order
  for(i = 0; i < numLRUOrderChange; i++)
  {
      pinPage(bm, h, orderRequests[i]);
      unpinPage(bm, h);
      ASSERT_EQUALS_POOL(poolContents[snapshot++], bm, "check pool content using pages");
  }

  // replace pages and check that it happens in LRU order
  for(i = 0; i < 5; i++)
  {
      pinPage(bm, h, 5 + i);
      unpinPage(bm, h);
      ASSERT_EQUALS_POOL(poolContents[snapshot++], bm, "check pool content using pages");
  }

  // check number of write IOs
  ASSERT_EQUALS_INT(0, getNumWriteIO(bm), "check number of write I/Os");
  ASSERT_EQUALS_INT(10, getNumReadIO(bm), "check number of read I/Os");

  CHECK(shutdownBufferPool(bm));
  CHECK(destroyPageFile("testbuffer.bin"));

  free(bm);
  free(h);
  TEST_DONE();
}
void
testFIFO ()
{
  // expected results
  const char *poolContents[] = { 
    "[0 0],[-1 0],[-1 0]" , 
    "[0 0],[1 0],[-1 0]", 
    "[0 0],[1 0],[2 0]", 
    "[3 0],[1 0],[2 0]", 
    "[3 0],[4 0],[2 0]",
    "[3 0],[4 1],[2 0]",
    "[3 0],[4 1],[5x0]",
    "[6x0],[4 1],[5x0]",
    "[6x0],[4 1],[0x0]",
    "[6x0],[4 0],[0x0]",
    "[6 0],[4 0],[0 0]"
  };
  const int requests[] = {0,1,2,3,4,4,5,6,0};
  const int numLinRequests = 5;
  const int numChangeRequests = 3;

  int i;
  BM_BufferPool *bm = MAKE_POOL();
  BM_PageHandle *h = MAKE_PAGE_HANDLE();
  testName = "Testing FIFO page replacement";

  CHECK(createPageFile("testbuffer.bin"));

  createDummyPages(bm, 100);

  CHECK(initBufferPool(bm, "testbuffer.bin", 3, RS_FIFO, NULL));

  // reading some pages linearly with direct unpin and no modifications
  for(i = 0; i < numLinRequests; i++)
    {
      pinPage(bm, h, requests[i]);
      unpinPage(bm, h);
      ASSERT_EQUALS_POOL(poolContents[i], bm, "check pool content");
    }

  // pin one page and test remainder
  i = numLinRequests;
  pinPage(bm, h, requests[i]);
  ASSERT_EQUALS_POOL(poolContents[i],bm,"pool content after pin page");

  // read pages and mark them as dirty
  for(i = numLinRequests + 1; i < numLinRequests + numChangeRequests + 1; i++)
    {
      pinPage(bm, h, requests[i]);
      markDirty(bm, h);
      unpinPage(bm, h);
      ASSERT_EQUALS_POOL(poolContents[i], bm, "check pool content");
    }

  // flush buffer pool to disk
  i = numLinRequests + numChangeRequests + 1;
  h->pageNum = 4;
  unpinPage(bm, h);
  ASSERT_EQUALS_POOL(poolContents[i],bm,"unpin last page");
  
  i++;
  forceFlushPool(bm);
  ASSERT_EQUALS_POOL(poolContents[i],bm,"pool content after flush");

  // check number of write IOs
  ASSERT_EQUALS_INT(3, getNumWriteIO(bm), "check number of write I/Os");
  ASSERT_EQUALS_INT(8, getNumReadIO(bm), "check number of read I/Os");

  CHECK(shutdownBufferPool(bm));
  CHECK(destroyPageFile("testbuffer.bin"));

  free(bm);
  free(h);
  TEST_DONE();
}
// test the CLOCK page replacement strategy
void
testClock (void)
{
    // expected results
    const char *poolContents[] = {
        // read first five pages and directly unpin them
        "[0 0],[-1 0],[-1 0]" ,
        "[0 0],[1 0],[-1 0]" ,
        "[2 0],[1 0],[-1 0]" ,
        "[2 0],[1 0],[3 0]" ,
        
        // pin the page 2 again
        "[2 0],[1 0],[3 0]" ,
        
        // read other pages use pin_CLOCK
        "[2 0],[4 0],[3 0]" ,
        "[5 0],[4 0],[3 0]" ,
        "[6 0],[4 0],[3 0]",
        "[6 0],[7 0],[3 0]"
    };
    const int orderRequests[] = {2};
    const int numrfChange = 1;
    
    int i;
    int snapshot = 0;
    BM_BufferPool *bm = MAKE_POOL();
    BM_PageHandle *h = MAKE_PAGE_HANDLE();
    testName = "Testing CLOCK page replacement";
    
    CHECK(createPageFile("testbuffer.bin"));
    createDummyPages(bm, 100);
    CHECK(initBufferPool(bm, "testbuffer.bin", 3, RS_CLOCK, NULL));
    
    // reading first five pages linearly with direct unpin and no modifications
    for(i = 0; i <4; i++)
    {
        pinPage(bm, h, i);
        unpinPage(bm, h);
        ASSERT_EQUALS_POOL(poolContents[snapshot++], bm, "check pool content reading in pages");
    }
    // read pages to rf of the frames
    for(i = 0; i < numrfChange; i++)
    {
        pinPage(bm, h, orderRequests[i]);
        unpinPage(bm, h);
        ASSERT_EQUALS_POOL(poolContents[snapshot++], bm, "check pool content using pages");
    }
    
    // replace pages and check that it happens in LRU_K order
    for(i = 0; i < 4; i++)
    {
        pinPage(bm, h, 4 + i);
        unpinPage(bm, h);
        ASSERT_EQUALS_POOL(poolContents[snapshot++], bm, "check pool content using pages");
        
    }
    
    // check number of write IOs
    ASSERT_EQUALS_INT(0, getNumWriteIO(bm), "check number of write I/Os");
    ASSERT_EQUALS_INT(8, getNumReadIO(bm), "check number of read I/Os");
    
    CHECK(shutdownBufferPool(bm));
    CHECK(destroyPageFile("testbuffer.bin"));
    
    free(bm);
    free(h);
    TEST_DONE();
}
//Clock[START]
void testClock()
{
	// expected results
	  const char *poolContents[] = {
			  "[0 0],[-1 0],[-1 0]",
			  	  "[0 0],[4 0],[-1 0]",
			  	  "[0 0],[4 0],[1 0]",
			  	  "[0 0],[4 0],[1 0]",
			  	  "[2 0],[4 0],[1 0]",
			  	  "[2 0],[4 0],[1 0]",
			  	  "[2 0],[4 0],[3 0]",
			  	  "[2 0],[4 0],[3 0]",
			  	  "[2 0],[4 0],[3 0]",
			  	  "[2 0],[4 0],[3 0]",
			  	  "[2 0],[4 0],[0 0]",
			  	  "[2 0],[4 0],[0 0]",
			  	  "[1 0],[4 0],[0 0]",
			  	  "[1 0],[4 0],[0 0]",
			  	  "[1 0],[4 0],[2 0]",
			  	  "[1 0],[4 0],[2 0]",
			  	  "[3 0],[4 0],[2 0]",
			  	  "[3 0],[4 0],[2 0]",
				  "[3 0],[4 0],[2 0]",
	  };
	  const int requests[] = {0,4,1,4,2,4,3,4,2,4,0,4,1,4,2,4,3,4};


	  int i;
	  BM_BufferPool *bm = MAKE_POOL();
	  BM_PageHandle *h = MAKE_PAGE_HANDLE();
	  testName = "Testing CLOCK page replacement";

	  CHECK(createPageFile("testbuffer.bin"));

	  createDummyPages(bm, 100);

	  CHECK(initBufferPool(bm, "testbuffer.bin", 3, RS_CLOCK, NULL));

	  // reading some pages linearly with direct unpin and no modifications
	  for(i = 0; i < 18; i++)
	    {
	      pinPage(bm, h, requests[i]);
	      unpinPage(bm, h);
	      ASSERT_EQUALS_POOL(poolContents[i], bm, "check pool content");
	    }


 	  forceFlushPool(bm);
	  ASSERT_EQUALS_POOL(poolContents[i],bm,"pool content after flush");

	  // check number of write IOs
	  //0 writes because no dirty pages were present
	  ASSERT_EQUALS_INT(0, getNumWriteIO(bm), "check number of write I/Os");


	  ASSERT_EQUALS_INT(9, getNumReadIO(bm), "check number of read I/Os");

	  CHECK(shutdownBufferPool(bm));
	  CHECK(destroyPageFile("testbuffer.bin"));

	  free(bm);
	  free(h);
	  TEST_DONE();

}
void testLFU()
{
	// expected results
	  const char *poolContents[] = {
		//Pin and Unpin 3 pages
	    "[0 0],[-1 0],[-1 0]" ,
	    "[0 0],[1 0],[-1 0]",
	    "[0 0],[1 0],[2 0]",

		//Pin the 0th page thrice,1st page twice
		"[0 3],[1 2],[2 0]",

		//Now pin a new page say 4. 4 should replace page 2 as page 2 has been Least Freq Used.
		"[0 3],[1 2],[4 1]",

		//Pin the 4th page thrice
		"[0 3],[1 2],[4 4]",

		//Now pin a new page 5. 5 should replace page 1 as page 1 has been Least Freq Used.
		"[0 3],[5 1],[4 4]",

		//Unpin page 0 thrice, page 5 once and page 4 four times.
		"[0 0],[5 0],[4 0]",
	  };
	  const int requests[] = {0,1,2,3,4,5,6};
	  const int numLinRequests = 3;

	  int i;
	  BM_BufferPool *bm = MAKE_POOL();
	  BM_PageHandle *h = MAKE_PAGE_HANDLE();
	  testName = "Testing LFU page replacement";

	  CHECK(createPageFile("testbuffer.bin"));

	  createDummyPages(bm, 100);

	  CHECK(initBufferPool(bm, "testbuffer.bin", 3, RS_LFU, NULL));

	  // reading some pages linearly with direct unpin and no modifications
	  for(i = 0; i < numLinRequests; i++)
	    {
	      pinPage(bm, h, requests[i]);
	      unpinPage(bm, h);
	      ASSERT_EQUALS_POOL(poolContents[i], bm, "check pool content");
	    }


	  pinPage(bm, h, 0);
	  pinPage(bm, h, 0);
	  pinPage(bm, h, 0);
	  pinPage(bm, h, 1);
	  pinPage(bm, h, 1);
	  ASSERT_EQUALS_POOL(poolContents[i++],bm,"pool content after pin page");

	  pinPage(bm, h, 4);
	  ASSERT_EQUALS_POOL(poolContents[i++],bm,"pool content after pin page");

	  pinPage(bm,h,4);
	  pinPage(bm,h,4);
	  pinPage(bm,h,4);
	  ASSERT_EQUALS_POOL(poolContents[i++],bm,"pool content after pin page");

	  pinPage(bm,h,5);
	  ASSERT_EQUALS_POOL(poolContents[i++],bm,"pool content after pin page");


	  h->data = "Page-0";
	  h->pageNum = 0;
	  unpinPage(bm,h);
	  unpinPage(bm,h);
	  unpinPage(bm,h);

	  h->data = "Page-5";
	  h->pageNum = 5;
	  unpinPage(bm,h);

	  h->data = "Page-4";
	  h->pageNum = 4;
	  unpinPage(bm,h);
	  unpinPage(bm,h);
	  unpinPage(bm,h);
	  unpinPage(bm,h);
 	  forceFlushPool(bm);
	  ASSERT_EQUALS_POOL(poolContents[i],bm,"pool content after flush");

	  // check number of write IOs
	  //0 writes because no dirty pages were present
	  ASSERT_EQUALS_INT(0, getNumWriteIO(bm), "check number of write I/Os");


	  ASSERT_EQUALS_INT(5, getNumReadIO(bm), "check number of read I/Os");

	  CHECK(shutdownBufferPool(bm));
	  CHECK(destroyPageFile("testbuffer.bin"));

	  free(bm);
	  free(h);
	  TEST_DONE();

}