lzo		zlib		non-compress
     5GBytes
total time(sec)			238		464		252
total time ratio(%)		94.4		184.1		100
output size(KBytes)		4812695		4771490		5156005
compression size ratio(%)	93.2		92.4		100


     7.5GBytes
total time(sec)			358		685		376
total time ratio(%)		95.2		182.1		100
output size(KBytes)		7193681		7130501		7782665
compression size ratio(%)	92.4		91.6		100


     10GBytes
total time(sec)			493		929		527
total time ratio(%)		93.5		176.3		100
output size(KBytes)		9980424		9932498		10460825
compression size ratio(%)	95.4		94.9		100



[about sample data]

Sample data is random, and it has deviation in compression ratio.
I show the number of pages below which were compressed.
(See attached patch "compressed_page_report.patch")

					lzo			zlib
	5GByte
compressed page				120052			122238
non-compressed page			1505548			1503362
compression page ratio(%)   		7.39			7.52


	7.5GByte
compressed page				206481			209758
non-compressed page			2071919			2068642
compression page ratio(%)   		9.06			9.21


	10GByte	
compressed page				160327			161229
non-compressed page			2783673			2782771
compression page ratio(%)		5.45			5.48