On CPU cache access - cpu-cache

Question

I decided to experiment with the code examples from the paper What Every Programmer Should Know About Memory (PDF), and saw a different result from section 6.2.
The programs are doing matrix multiplications, I have made a little change and put them at https://github.com/herberteuler/cpumemory.
In the paper, it is said that the optimization from matrix1.c to matrix2.c, by transposing the second matrix, could save about 76.6% of cpu cycles (section 6.2.1, page 50):
Original Transposed
Cycles 16,765,297,870 3,922,373,010
Relative 100% 23.4%
But on my node, the result is very different from the above list.
This is my kernel and CPU information:
$ uname -a
Linux herberteuler 3.9-1-amd64 #1 SMP Debian 3.9.8-1 x86_64 GNU/Linux
$ cat /proc/cpuinfo
processor : 0
vendor_id : GenuineIntel
cpu family : 6
model : 23
model name : Intel(R) Core(TM)2 Duo CPU P8600 # 2.40GHz
stepping : 10
microcode : 0xa07
cpu MHz : 2401.000
cache size : 3072 KB
physical id : 0
siblings : 2
core id : 0
cpu cores : 2
apicid : 0
initial apicid : 0
fpu : yes
fpu_exception : yes
cpuid level : 13
wp : yes
flags : fpu vme de pse tsc msr pae mce cx8 apic sep mtrr pge mca cmov pat pse36 clflush dts acpi mmx fxsr sse sse2 ss ht tm pbe syscall nx lm constant_tsc arch_perfmon pebs bts rep_good nopl aperfmperf pni dtes64 monitor ds_cpl vmx smx est tm2 ssse3 cx16 xtpr pdcm sse4_1 xsave lahf_lm ida dtherm tpr_shadow vnmi flexpriority
bogomips : 4788.33
clflush size : 64
cache_alignment : 64
address sizes : 36 bits physical, 48 bits virtual
power management:
processor : 1
vendor_id : GenuineIntel
cpu family : 6
model : 23
model name : Intel(R) Core(TM)2 Duo CPU P8600 # 2.40GHz
stepping : 10
microcode : 0xa07
cpu MHz : 800.000
cache size : 3072 KB
physical id : 0
siblings : 2
core id : 1
cpu cores : 2
apicid : 1
initial apicid : 1
fpu : yes
fpu_exception : yes
cpuid level : 13
wp : yes
flags : fpu vme de pse tsc msr pae mce cx8 apic sep mtrr pge mca cmov pat pse36 clflush dts acpi mmx fxsr sse sse2 ss ht tm pbe syscall nx lm constant_tsc arch_perfmon pebs bts rep_good nopl aperfmperf pni dtes64 monitor ds_cpl vmx smx est tm2 ssse3 cx16 xtpr pdcm sse4_1 xsave lahf_lm ida dtherm tpr_shadow vnmi flexpriority
bogomips : 4788.33
clflush size : 64
cache_alignment : 64
address sizes : 36 bits physical, 48 bits virtual
power management:
And this is the result of executing matrix1 and matrix2:
$ ./matrix1
cpu cycles: 18071621964
$ ./matrix2
cpu cycles: 15716582775
Why don't I see the huge reduction of CPU cycles in matrix2, as expected?
Thanks in advance.