$ ./opt-O0/usr/bin/7za b

7-Zip (A) 9.13 beta  Copyright (c) 1999-2010 Igor Pavlov  2010-04-15
p7zip Version 9.13 (locale=en_US.utf8,Utf16=on,HugeFiles=on,1 CPU)

RAM size:     243 MB,  # CPU hardware threads:   1
RAM usage:    211 MB,  # Benchmark threads:      1

Dict        Compressing          |        Decompressing
      Speed Usage    R/U Rating  |    Speed Usage    R/U Rating
       KB/s     %   MIPS   MIPS  |     KB/s     %   MIPS   MIPS

22:     115   100    112    112  |     1467   100    132    132
23:     114   100    116    116  |     1456   100    133    133
24:     112   100    121    121  |     1442   100    134    133
----------------------------------------------------------------
Avr:          100    116    116               100    133    133
Tot:          100    125    124

$ ./opt-O1/usr/bin/7za b

7-Zip (A) 9.13 beta  Copyright (c) 1999-2010 Igor Pavlov  2010-04-15
p7zip Version 9.13 (locale=en_US.utf8,Utf16=on,HugeFiles=on,1 CPU)

RAM size:     243 MB,  # CPU hardware threads:   1
RAM usage:    211 MB,  # Benchmark threads:      1

Dict        Compressing          |        Decompressing
      Speed Usage    R/U Rating  |    Speed Usage    R/U Rating
       KB/s     %   MIPS   MIPS  |     KB/s     %   MIPS   MIPS

22:     193   100    188    188  |     3589   100    324    324
23:     190   100    194    194  |     3550   100    325    325
24:     185   100    199    199  |     3502   100    325    325
----------------------------------------------------------------
Avr:          100    194    193               100    325    324
Tot:          100    259    259

$ ./opt-O2/usr/bin/7za b

7-Zip (A) 9.13 beta  Copyright (c) 1999-2010 Igor Pavlov  2010-04-15
p7zip Version 9.13 (locale=en_US.utf8,Utf16=on,HugeFiles=on,1 CPU)

RAM size:     243 MB,  # CPU hardware threads:   1
RAM usage:    211 MB,  # Benchmark threads:      1

Dict        Compressing          |        Decompressing
      Speed Usage    R/U Rating  |    Speed Usage    R/U Rating
       KB/s     %   MIPS   MIPS  |     KB/s     %   MIPS   MIPS

22:     217   100    211    211  |     3993   100    360    360
23:     213   100    217    217  |     3944   100    361    361
24:     205   100    221    220  |     3887   100    360    360
----------------------------------------------------------------
Avr:          100    216    216               100    360    360
Tot:          100    288    288

$ ./opt-O3/usr/bin/7za b

7-Zip (A) 9.13 beta  Copyright (c) 1999-2010 Igor Pavlov  2010-04-15
p7zip Version 9.13 (locale=en_US.utf8,Utf16=on,HugeFiles=on,1 CPU)

RAM size:     243 MB,  # CPU hardware threads:   1
RAM usage:    211 MB,  # Benchmark threads:      1

Dict        Compressing          |        Decompressing
      Speed Usage    R/U Rating  |    Speed Usage    R/U Rating
       KB/s     %   MIPS   MIPS  |     KB/s     %   MIPS   MIPS

22:     217   100    211    211  |     4021   100    364    363
23:     212   100    216    216  |     3994   100    365    365
24:     207   100    223    223  |     3941   100    365    365
----------------------------------------------------------------
Avr:          100    217    217               100    365    364
Tot:          100    291    291

$ ./opt-Os/usr/bin/7za b

7-Zip (A) 9.13 beta  Copyright (c) 1999-2010 Igor Pavlov  2010-04-15
p7zip Version 9.13 (locale=en_US.utf8,Utf16=on,HugeFiles=on,1 CPU)

RAM size:     243 MB,  # CPU hardware threads:   1
RAM usage:    211 MB,  # Benchmark threads:      1

Dict        Compressing          |        Decompressing
      Speed Usage    R/U Rating  |    Speed Usage    R/U Rating
       KB/s     %   MIPS   MIPS  |     KB/s     %   MIPS   MIPS

22:     217   100    211    211  |     4213   100    380    380
23:     213   100    217    217  |     4162   100    380    381
24:     208   100    224    223  |     4102   100    381    380
----------------------------------------------------------------
Avr:          100    217    217               100    380    380
Tot:          100    299    299