W
winter heat
The following program will take 3.6 seconds to run on a Macbook that has
2.2GHz Core 2 Duo, and 1.8 seconds to run on a Macbook Pro that has
2.53GHz Core 2 Duo.
That's a bit weird... why doubling the speed when the CPU is only 15%
faster in clock speed? I double checked the CPU meter to make sure none
of the 2 cores are in 100% usage (so as to see the CPU is not busy
running something else). Could it be because one is Mac OS X Leopard
and one is Mac OS X Snow Leopard (64 bit)? Both are running Ruby 1.9.2.
------------------------------------------------------------
p RUBY_VERSION
p RUBY_DESCRIPTION if defined? RUBY_DESCRIPTION
n = 9_999_999
p n
t = 0; 1.upto(n) {|i| t += i if i%3==0 || i%5==0}; p t
------------------------------------------------------------
2.2GHz Core 2 Duo
$ time ruby 1.rb
"1.9.2"
"ruby 1.9.2p0 (2010-08-18 revision 29036) [i386-darwin9.8.0]"
9999999
23333331666668
real 0m3.784s
user 0m3.751s
sys 0m0.021s
------------------------------------------------------------
2.53GHz Intel Core 2 Duo
$ time ruby 1.rb
"1.9.2"
"ruby 1.9.2p0 (2010-08-18 revision 29036) [x86_64-darwin10.4.0]"
9999999
23333331666668
real 0m1.893s
user 0m1.809s
sys 0m0.012s
------------------------------------------------------------
Test run on Windows 7:
time_start = Time.now
p RUBY_VERSION
p RUBY_DESCRIPTION if defined? RUBY_DESCRIPTION
n = 9_999_999
p n
t = 0; 1.upto(n) {|i| t += i if i%3==0 || i%5==0}; p t
print "Took #{Time.now - time_start} seconds to run\n"
------------------------------------------------------------
Intel Q6600 Quad Core 2.4GHz running Windows 7, 64-bit
C:\> ruby try.rb
"1.9.2"
"ruby 1.9.2p0 (2010-08-18) [i386-mingw32]"
9999999
23333331666668
Took 3.248186 seconds to run
------------------------------------------------------------
Intel 920 i7 2.67GHz running Windows 7, 64-bit
C:\> ruby try.rb
"1.9.2"
"ruby 1.9.2p0 (2010-08-18) [i386-mingw32]"
9999999
23333331666668
Took 2.044117 seconds to run
2.2GHz Core 2 Duo, and 1.8 seconds to run on a Macbook Pro that has
2.53GHz Core 2 Duo.
That's a bit weird... why doubling the speed when the CPU is only 15%
faster in clock speed? I double checked the CPU meter to make sure none
of the 2 cores are in 100% usage (so as to see the CPU is not busy
running something else). Could it be because one is Mac OS X Leopard
and one is Mac OS X Snow Leopard (64 bit)? Both are running Ruby 1.9.2.
------------------------------------------------------------
p RUBY_VERSION
p RUBY_DESCRIPTION if defined? RUBY_DESCRIPTION
n = 9_999_999
p n
t = 0; 1.upto(n) {|i| t += i if i%3==0 || i%5==0}; p t
------------------------------------------------------------
2.2GHz Core 2 Duo
$ time ruby 1.rb
"1.9.2"
"ruby 1.9.2p0 (2010-08-18 revision 29036) [i386-darwin9.8.0]"
9999999
23333331666668
real 0m3.784s
user 0m3.751s
sys 0m0.021s
------------------------------------------------------------
2.53GHz Intel Core 2 Duo
$ time ruby 1.rb
"1.9.2"
"ruby 1.9.2p0 (2010-08-18 revision 29036) [x86_64-darwin10.4.0]"
9999999
23333331666668
real 0m1.893s
user 0m1.809s
sys 0m0.012s
------------------------------------------------------------
Test run on Windows 7:
time_start = Time.now
p RUBY_VERSION
p RUBY_DESCRIPTION if defined? RUBY_DESCRIPTION
n = 9_999_999
p n
t = 0; 1.upto(n) {|i| t += i if i%3==0 || i%5==0}; p t
print "Took #{Time.now - time_start} seconds to run\n"
------------------------------------------------------------
Intel Q6600 Quad Core 2.4GHz running Windows 7, 64-bit
C:\> ruby try.rb
"1.9.2"
"ruby 1.9.2p0 (2010-08-18) [i386-mingw32]"
9999999
23333331666668
Took 3.248186 seconds to run
------------------------------------------------------------
Intel 920 i7 2.67GHz running Windows 7, 64-bit
C:\> ruby try.rb
"1.9.2"
"ruby 1.9.2p0 (2010-08-18) [i386-mingw32]"
9999999
23333331666668
Took 2.044117 seconds to run