def test5(self):
print("======= TEST5 ======")
print(
"Scenario: more pages than frames (number of pages = (2 * number of frames) + 1)\n"
)
status = True
print("1) Create a buffer pool of five frames...\n")
buf = bufferManager(5)
print("2) Try to pin 11 new pages and write something in each page ")
print(
"Requires pinning the first five pages (600 to 604), then pinning the second five pages (605 to 609), then pinning the eleventh page (page #610)"
)
print("")
for i in range(11):
pageNumber = i + 600
pageX = buf.pin(pageNumber, True)
pageX.content = "content {}".format(pageNumber)
buf.unpin((pageNumber), True)
print(".... Pinning of 11 pages suceeded\n")
#buf.printBufferContent()
print("3) Try to read the content of pages with odd page number")
for i in range(1, 11, 2):
pageNumber = i + 600
pageX = buf.pin(pageNumber, False)
if pageX.content != "content {}".format(pageNumber):
print("....Error: page {} content is not correct\n".format(
pageNumber))
status = False
return status
print(pageX.content)
buf.unpin((pageNumber), False)
print(".... Reading pages with odd page number succeeded.\n")
print("")
print("4) Try to read the content of pages with even page number")
for i in range(0, 11, 2):
pageNumber = i + 600
pageX = buf.pin(pageNumber, False)
if pageX.content != "content {}".format(pageNumber):
print("....Error: page {} content is not correct\n".format(
pageNumber))
status = False
return status
print(pageX.content)
buf.unpin((pageNumber), False)
print(".... Reading pages with even page number succeeded.\n")
print("")
print("Test5 completed successfully...\n")
print("")
return status
def test4(self):
status = True
print("======= TEST4 ======")
print("Two transactions pin the same page with one of them writing to it\n")
print("1) Create a buffer pool of five frames...\n")
buf = bufferManager(5)
pageNumber = 350
print("2) Pin new page {}, modify its content, then unpin with dirtyBit=True\n".format(pageNumber))
pageX = buf.pin(pageNumber, True)
pageX.content = "content {}".format(pageNumber)
buf.unpin((pageNumber), True)
#buf.printBufferContent()
pageNumber = 350
print("3) Pin page {} again, then unpin with dirtyBit=False (e.g., a read-only transaction)".format(pageNumber))
print("expecting that dirty bit stays True\n")
pageX = buf.pin(pageNumber, False)
buf.unpin((pageNumber), False)
#buf.printBufferContent()
print("4) Pin 5 pages so page {} is evicted from buffer pool".format(pageNumber))
print("Dirty bit of Page {} should be True, thereofre, the page should be written to disk\n".format(pageNumber))
for i in range(5):
pageNo = i + 300
pageX = buf.pin(pageNo, True)
for i in range(5):
pageNo = i + 300
buf.unpin((pageNo), False)
#buf.printBufferContent()
pageNumber = 350
print("5) pin page {} again and check its content (it should be read from disk)".format(pageNumber))
pageX = buf.pin(pageNumber, False)
#buf.printBufferContent()
if pageX.content != "content {}".format(pageNumber):
print("..... Error: page {} content is not correct\n".format(pageNumber))
status = False
return status
else:
print("..... Page {} content is correct!\n".format(pageNumber))
print("Test4 completed successfully...\n")
return status
def test3(self):
status = True
print("======= TEST3 ======")
print("Scenario: Buffer pool full, cannot pin another page!\n")
print("1) Create a buffer pool of five frames\n")
buf = bufferManager(5)
print("2) Pin five new pages without unpinning them\n")
for i in range(5):
pageNumber = i + 200
pageX = buf.pin(pageNumber, True)
print(
"3) Try to pin a sixth page, since buffer pool is full (all pages in buffer have pinCount =1),"
)
print("we should get a BufferPoolFullError exception")
pageNumber = 5 + 200
try:
pageX = buf.pin(pageNumber, True)
except BufferPoolFullError:
print(".... Expected BufferPoolFullError exception raised\n")
status = True
except:
print(".... Unexpected error:\n", sys.exc_info()[0])
status = False
print(
"4) Now unpin one of the five pages, so we have one available frame\n"
)
pageNumber = 4 + 200
buf.unpin((pageNumber), False)
print(
"5) Try to pin a sixth page, we should be able to do that this time"
)
pageNumber = 5 + 200
try:
pageX = buf.pin(pageNumber, True)
print(".... pinning a sixth page succeeded as expected\n")
except:
print(".... Unexpected error:\n", sys.exc_info()[0])
status = False
print("Test3 completed successfully...\n")
print("")
return status
def test2(self):
print("======= TEST2 ======")
print(
"Scenario: more pages than frames (number of pages = 2 * number of frames)\n"
)
status = True
print("1) Create a buffer pool of five frames...\n")
buf = bufferManager(5)
#buf.printBufferContent()
print("2) Try to pin 10 new pages and write something in each page ")
print(
"Requires that first five pages are evicted from buffer pool (and written to disk),"
)
print("so the last five pages are pinned")
print("")
for i in range(10): #change to 10
pageNumber = i + 100
#buf.printBufferContent()
pageX = buf.pin(pageNumber, True)
#buf.printBufferContent()
pageX.content = "content {}".format(pageNumber)
print(pageX.content)
buf.unpin((pageNumber), True)
#buf.printBufferContent()
print(".... Pinning of 10 pages suceeded\n")
buf.printBufferContent()
print("3) Try to read the content of the 10 created pages")
for i in range(10):
pageNumber = i + 100
pageX = buf.pin(pageNumber, False)
print(pageX.content)
if pageX.content != "content {}".format(pageNumber):
print("....Error: page {} content is not correct\n".format(
pageNumber))
status = False
return status
buf.unpin((pageNumber), False)
print(".... Reading the 10 pages succeeded.\n")
print("Test2 completed successfully...\n")
print("")
return status