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performance puzzle

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  • S Super Lloyd

    indeed, but they had this propaganda that .NET is JIT compiled just for the machine it's running on, so that theoretically it can even be faster! (it's what they used to say) Further C# 4 is way faster and this algorithm is so simple I can hardly see why the JITted version couldn't be as good as the compiled C version... guess I was wrong.. guess when things are looped over a huge number of time, just 1 instruction can make a big difference....

    A train station is where the train stops. A bus station is where the bus stops. On my desk, I have a work station.... _________________________________________________________ My programs never have bugs, they just develop random features.

    C Offline
    C Offline
    CPallini
    wrote on last edited by
    #24

    Super Lloyd wrote:

    indeed, but they had this propaganda that .NET is JIT compiled just for the machine it's running on, so that theoretically it can even be faster!

    I guess this happens also for C++, in this case. :)

    If the Lord God Almighty had consulted me before embarking upon the Creation, I would have recommended something simpler. -- Alfonso the Wise, 13th Century King of Castile.
    This is going on my arrogant assumptions. You may have a superb reason why I'm completely wrong. -- Iain Clarke
    [My articles]

    S 1 Reply Last reply
    0
    • C CPallini

      Super Lloyd wrote:

      indeed, but they had this propaganda that .NET is JIT compiled just for the machine it's running on, so that theoretically it can even be faster!

      I guess this happens also for C++, in this case. :)

      If the Lord God Almighty had consulted me before embarking upon the Creation, I would have recommended something simpler. -- Alfonso the Wise, 13th Century King of Castile.
      This is going on my arrogant assumptions. You may have a superb reason why I'm completely wrong. -- Iain Clarke
      [My articles]

      S Offline
      S Offline
      Super Lloyd
      wrote on last edited by
      #25

      Mmm... indeed! Silly me! :laugh:

      A train station is where the train stops. A bus station is where the bus stops. On my desk, I have a work station.... _________________________________________________________ My programs never have bugs, they just develop random features.

      1 Reply Last reply
      0
      • L Lost User

        Super Lloyd wrote:

        how do I get the disassembly of the JITted code?!

        Like I said, throw an uncaught exception. Attach the debugger when it is thrown. To prevent certain optimizations, ensure that throwing the exceptions happens at a place that the compiler can't prove will be reached. Then open the disassembly view. (doesn't exist in express editions)

        S Offline
        S Offline
        Super Lloyd
        wrote on last edited by
        #26

        Cool, I have both assembly version side by side now! :) Mm.. the C++ has much short loop! (I mean much less assembly instruction in the loop) :~ Now trying to read the ASM closely and guess what went "wrong" in the C# version...

        A train station is where the train stops. A bus station is where the bus stops. On my desk, I have a work station.... _________________________________________________________ My programs never have bugs, they just develop random features.

        L 1 Reply Last reply
        0
        • S Simon P Stevens

          Cool. I'm looking at it now. I'll post back in a bit.

          Simon

          S Offline
          S Offline
          Super Lloyd
          wrote on last edited by
          #27

          yes, do post back please! :P

          A train station is where the train stops. A bus station is where the bus stops. On my desk, I have a work station.... _________________________________________________________ My programs never have bugs, they just develop random features.

          S 1 Reply Last reply
          0
          • S Super Lloyd

            Cool, I have both assembly version side by side now! :) Mm.. the C++ has much short loop! (I mean much less assembly instruction in the loop) :~ Now trying to read the ASM closely and guess what went "wrong" in the C# version...

            A train station is where the train stops. A bus station is where the bus stops. On my desk, I have a work station.... _________________________________________________________ My programs never have bugs, they just develop random features.

            L Offline
            L Offline
            Lost User
            wrote on last edited by
            #28

            Post it?

            S 2 Replies Last reply
            0
            • M Mechanical

              Super Lloyd wrote:

              any C# performance tip is welcome!

              That is like looking for performance from Java: You won't get it. If you need (or want) performance, don't do retards' languages. I know this thread isn't meant to incite hatred against retards' languages.

              NULL

              A Offline
              A Offline
              Aamir Butt
              wrote on last edited by
              #29

              Mechanical wrote:

              That is like looking for performance from Java: You won't get it.

              You are horribly wrong here. In some cases, C# can outperform C/C++ performance-wise. And that is because of the optimizations that can be made at intermediate-level i.e, IL or bytecode or whatever (which people like you think might be the reason for slowness). See here for a performance comparison between different languages[^] However, if you like to follow the sheep, go ahead.

              D M 2 Replies Last reply
              0
              • S Super Lloyd

                C++ ======================================

                int _tmain(int argc, _TCHAR* argv[])
                {
                if (argc != 2)
                {
                std::cerr << "Usage:\tsieve [iterations]\n";
                return 1;
                };

                size\_t NUM = \_wtoi(argv\[1\]);
                DWORD dw = ::GetTickCount();
                

                #if ! CS-Speed
                char primes[8192+1];
                int pbegin = 0;
                int begin = 2;
                int end = 8193;

                while (NUM -- != 0)
                {
                		for (int i = 0; i < end; i++)
                		{
                				primes\[i\] = 1;
                		}
                
                		for (int i = begin; i < end; ++i)
                		{
                				if (primes\[i\] != 0)
                				{
                						int p = i; // using this extra variable speeds up C++!!! (and slow down C# if I do it)
                						for (int k = i + p; k < end; k += p)
                						{
                								primes\[k\] = 0;
                						}
                				}
                		}
                }
                

                #else
                WORD end = 8193;
                char primes[8193];
                while (NUM-- != 0)
                {
                for (WORD i = 0; i < end; i++)
                primes[i] = 1;

                	for (WORD i = 2; i < end; ++i)
                		if (primes\[i\] != 0)
                			for (WORD k = 2 \* i; k < end; k += i)
                				primes\[k\] = 0;
                }
                

                #endif

                DWORD dw2 = ::GetTickCount();
                std::cout << "Milliseconds = " << dw2-dw << std::endl;
                return 0;
                

                }

                ====================================== C# ======================================

                unsafe static void Main(string[] args)
                {
                if (args.Length != 1)
                {
                Console.WriteLine("Usage:\tsieve [iterations]");
                return;
                }

                int NUM = int.Parse(args\[0\]);
                var t0 = DateTime.Now;
                
                int end = 8193;
                var primes = stackalloc byte\[end\];
                while (NUM-- != 0)
                {
                	for (int i = 0; i < end; i++)
                		primes\[i\] = 1;
                
                	for (int i = 2; i < end; ++i)
                		if (primes\[i\] != 0)
                			for (int k = 2 \* i; k < end; k += i)
                				primes\[k\] = 0;
                }
                
                var dt = DateTime.Now - t0;
                System.Console.WriteLine("Milliseconds = {0}", dt.TotalMilliseconds);
                

                }

                ====================================== F# ======================================

                open System

                [<EntryPoint>]
                let main args =

                let NUM = Int32.Parse args.\[0\]
                let t0 = DateTime.Now
                
                let primes : byte\[\] = Array.zeroCreate ( 8192 + 1 )
                let aend = 8192
                for nloop = 1 to NUM do
                
                    for i = 0 to aend do
                        primes.\[i\] <- 1uy
                
                    for i = 2 to aend do
                        if primes.\[i\] <> 0uy then
                            let mutable k = 2 \* i
                            while k <= aend do
                                primes.\[k\] <- 0uy
                                k <- k + i
                
                
                let dt = DateTime.Now - t0
                Console.WriteLine("Milliseconds = {0}", dt.TotalMilliseconds)
                0
                

                ===============================

                D Offline
                D Offline
                DaveAuld
                wrote on last edited by
                #30

                Nothing to do with the optimisation, but what about using the StopWatch class instead of datetime? Start the stop watch immediately before you enter the loop, and then stop it as soon as the loop exists.

                Dave Find Me On: Web|Facebook|Twitter|LinkedIn CPRepWatcher now available as Packaged Chrome Extension, visit my articles for link.

                L S 2 Replies Last reply
                0
                • A Aamir Butt

                  Mechanical wrote:

                  That is like looking for performance from Java: You won't get it.

                  You are horribly wrong here. In some cases, C# can outperform C/C++ performance-wise. And that is because of the optimizations that can be made at intermediate-level i.e, IL or bytecode or whatever (which people like you think might be the reason for slowness). See here for a performance comparison between different languages[^] However, if you like to follow the sheep, go ahead.

                  D Offline
                  D Offline
                  Dan Neely
                  wrote on last edited by
                  #31

                  Aamir Butt wrote:

                  See here for a performance comparison between different languages[^]

                  The comments on that post were staggeringly stupid. :((

                  3x12=36 2x12=24 1x12=12 0x12=18

                  A 1 Reply Last reply
                  0
                  • S Super Lloyd

                    I have a short program which check prime number. Run multiple time a single slow loop, to test performance. I have a C++, C# and F# version. (to be fair with C# the C++ version use fixed sized 32 bit integers, instead of native size int, but that doesn't seem to make a difference anyway) A few things puzzle me. 1. The c++ is definitely faster! my best C# tweak makes C++ 20% faster. That surprises me because C# is compiled too (at runtime, at the first run) and I am only looping over byte array and using int number, I am not doing interop, and even I use stackalloc and pointer in (unsafe) C# so there is no bound check. And the algorithm is so simple that it's hard to believe (but it must be true) that the C++ compiler optimize the generated code further than the JITted C# one... 2. creating an array with stackalloc result in faster loop (5%) than using fixed(&array[0]), in fact using fixed(&array[0]) has the same speed than using normal (safe and bound checked) array!! how come!?! 3. F# is 25% slower than C#. Well I guess I should not be too surprised and I guess that teach me the posts about amazing performance of F# have less to do with some "magic F# quality" and more to do with the heavy type inference / use of generic and "fast delegate" replacement, which is not really put to use in my sample. So, what is the question? err.. Well, any C# performance tip is welcome!

                    A train station is where the train stops. A bus station is where the bus stops. On my desk, I have a work station.... _________________________________________________________ My programs never have bugs, they just develop random features.

                    R Offline
                    R Offline
                    realJSOP
                    wrote on last edited by
                    #32

                    Super Lloyd wrote:

                    Well, any C# performance tip is welcome!

                    Uncle John's Handy C# Performance Tip #237: Convert the code to unmanaged C++.

                    .45 ACP - because shooting twice is just silly
                    -----
                    "Why don't you tie a kerosene-soaked rag around your ankles so the ants won't climb up and eat your candy ass..." - Dale Earnhardt, 1997
                    -----
                    "The staggering layers of obscenity in your statement make it a work of art on so many levels." - J. Jystad, 2001

                    C S 2 Replies Last reply
                    0
                    • A Aamir Butt

                      Mechanical wrote:

                      That is like looking for performance from Java: You won't get it.

                      You are horribly wrong here. In some cases, C# can outperform C/C++ performance-wise. And that is because of the optimizations that can be made at intermediate-level i.e, IL or bytecode or whatever (which people like you think might be the reason for slowness). See here for a performance comparison between different languages[^] However, if you like to follow the sheep, go ahead.

                      M Offline
                      M Offline
                      Mechanical
                      wrote on last edited by
                      #33

                      Aamir Butt wrote:

                      In some cases, C# can outperform C/C++

                      How about ALL cases ? People who talk about C# (or any other retards' language) performance are talking about void while engaged with other C# (or any other retards' language) performance addicts in group masturbation. The link in your post points to another post by a C# guru (read as: VB guru). It says: "Remember : Engineers are expensive and servers are not!". Look at that! I mean just look at how pathetic that retard is.

                      Aamir Butt wrote:

                      However, if you like to follow the sheep, go ahead.

                      I'll bet you are one of those that believe Java is the future of 3D.

                      NULL

                      A 1 Reply Last reply
                      0
                      • R realJSOP

                        Super Lloyd wrote:

                        Well, any C# performance tip is welcome!

                        Uncle John's Handy C# Performance Tip #237: Convert the code to unmanaged C++.

                        .45 ACP - because shooting twice is just silly
                        -----
                        "Why don't you tie a kerosene-soaked rag around your ankles so the ants won't climb up and eat your candy ass..." - Dale Earnhardt, 1997
                        -----
                        "The staggering layers of obscenity in your statement make it a work of art on so many levels." - J. Jystad, 2001

                        C Offline
                        C Offline
                        CPallini
                        wrote on last edited by
                        #34

                        :-D 5.

                        If the Lord God Almighty had consulted me before embarking upon the Creation, I would have recommended something simpler. -- Alfonso the Wise, 13th Century King of Castile.
                        This is going on my arrogant assumptions. You may have a superb reason why I'm completely wrong. -- Iain Clarke
                        [My articles]

                        1 Reply Last reply
                        0
                        • L Lost User

                          Post it?

                          S Offline
                          S Offline
                          Super Lloyd
                          wrote on last edited by
                          #35

                          I already posted the source code: http://www.codeproject.com/Lounge.aspx?msg=3657380#xx3657380xx[^] As to the disassembly, err.... well, ok, but I have to cut the C++ version as it huge loads of stuff coming the #include(s), hopefully I'll cut it right ... disassembled JITted C#

                          --- C:\Dev\Test\Performance\CSperf\Program.cs ----------------------------------
                          if (args.Length != 1)
                          00000000 push ebp
                          00000001 mov ebp,esp
                          00000003 push edi
                          00000004 push esi
                          00000005 sub esp,6Ch
                          00000008 mov esi,ecx
                          0000000a lea edi,[ebp-74h]
                          0000000d mov ecx,1Bh
                          00000012 xor eax,eax
                          00000014 rep stos dword ptr es:[edi]
                          00000016 mov ecx,esi
                          00000018 mov dword ptr [ebp-0Ch],esp
                          0000001b mov dword ptr [ebp-74h],2941BF9Bh
                          00000022 mov dword ptr [ebp-60h],ecx
                          00000025 cmp dword ptr ds:[001B7CB8h],0
                          0000002c je 00000033
                          0000002e call 62889E21
                          00000033 xor edx,edx
                          00000035 mov dword ptr [ebp-28h],edx
                          00000038 xor edx,edx
                          0000003a mov dword ptr [ebp-1Ch],edx
                          0000003d xor edx,edx
                          0000003f mov dword ptr [ebp-24h],edx
                          00000042 xor edx,edx
                          00000044 mov dword ptr [ebp-2Ch],edx
                          00000047 xor edx,edx
                          00000049 mov dword ptr [ebp-20h],edx
                          0000004c xor edx,edx
                          0000004e mov dword ptr [ebp-10h],edx
                          00000051 mov eax,dword ptr [ebp-60h]
                          00000054 cmp dword ptr [eax+4],1
                          00000058 je 0000006B
                          {
                          Console.WriteLine("Usage:\tsieve [iterations]");
                          0000005a mov ecx,dword ptr ds:[03832088h]
                          00000060 call 62202DB4
                          return;
                          00000065 nop
                          00000066 jmp 0000019A
                          }

                          		int NUM = int.Parse(args\[0\]);
                          

                          0000006b mov eax,dword ptr [ebp-60h]
                          0000006e cmp dword ptr [eax+4],0
                          00000072 ja 00000079
                          00000074 call 6288BA5C
                          00000079 mov ecx,dword ptr [eax+0Ch]
                          0000007c call 6220EAC4
                          00000081 mov dword ptr [ebp-38h],eax
                          00000084 mov eax,dword ptr [ebp-38h]
                          00000087 mov dword ptr [ebp-10h],eax
                          var t0 = DateTime.Now;
                          0000008a lea ecx,[ebp-40h]
                          0000008d call 61D07768

                          L D 2 Replies Last reply
                          0
                          • S Super Lloyd

                            I already posted the source code: http://www.codeproject.com/Lounge.aspx?msg=3657380#xx3657380xx[^] As to the disassembly, err.... well, ok, but I have to cut the C++ version as it huge loads of stuff coming the #include(s), hopefully I'll cut it right ... disassembled JITted C#

                            --- C:\Dev\Test\Performance\CSperf\Program.cs ----------------------------------
                            if (args.Length != 1)
                            00000000 push ebp
                            00000001 mov ebp,esp
                            00000003 push edi
                            00000004 push esi
                            00000005 sub esp,6Ch
                            00000008 mov esi,ecx
                            0000000a lea edi,[ebp-74h]
                            0000000d mov ecx,1Bh
                            00000012 xor eax,eax
                            00000014 rep stos dword ptr es:[edi]
                            00000016 mov ecx,esi
                            00000018 mov dword ptr [ebp-0Ch],esp
                            0000001b mov dword ptr [ebp-74h],2941BF9Bh
                            00000022 mov dword ptr [ebp-60h],ecx
                            00000025 cmp dword ptr ds:[001B7CB8h],0
                            0000002c je 00000033
                            0000002e call 62889E21
                            00000033 xor edx,edx
                            00000035 mov dword ptr [ebp-28h],edx
                            00000038 xor edx,edx
                            0000003a mov dword ptr [ebp-1Ch],edx
                            0000003d xor edx,edx
                            0000003f mov dword ptr [ebp-24h],edx
                            00000042 xor edx,edx
                            00000044 mov dword ptr [ebp-2Ch],edx
                            00000047 xor edx,edx
                            00000049 mov dword ptr [ebp-20h],edx
                            0000004c xor edx,edx
                            0000004e mov dword ptr [ebp-10h],edx
                            00000051 mov eax,dword ptr [ebp-60h]
                            00000054 cmp dword ptr [eax+4],1
                            00000058 je 0000006B
                            {
                            Console.WriteLine("Usage:\tsieve [iterations]");
                            0000005a mov ecx,dword ptr ds:[03832088h]
                            00000060 call 62202DB4
                            return;
                            00000065 nop
                            00000066 jmp 0000019A
                            }

                            		int NUM = int.Parse(args\[0\]);
                            

                            0000006b mov eax,dword ptr [ebp-60h]
                            0000006e cmp dword ptr [eax+4],0
                            00000072 ja 00000079
                            00000074 call 6288BA5C
                            00000079 mov ecx,dword ptr [eax+0Ch]
                            0000007c call 6220EAC4
                            00000081 mov dword ptr [ebp-38h],eax
                            00000084 mov eax,dword ptr [ebp-38h]
                            00000087 mov dword ptr [ebp-10h],eax
                            var t0 = DateTime.Now;
                            0000008a lea ecx,[ebp-40h]
                            0000008d call 61D07768

                            L Offline
                            L Offline
                            Lost User
                            wrote on last edited by
                            #36

                            Are you sure you got the optimized version of the C# code? I mean, yea it's supposed to be lame, but it's worse than I expected

                            S 1 Reply Last reply
                            0
                            • R realJSOP

                              Super Lloyd wrote:

                              Well, any C# performance tip is welcome!

                              Uncle John's Handy C# Performance Tip #237: Convert the code to unmanaged C++.

                              .45 ACP - because shooting twice is just silly
                              -----
                              "Why don't you tie a kerosene-soaked rag around your ankles so the ants won't climb up and eat your candy ass..." - Dale Earnhardt, 1997
                              -----
                              "The staggering layers of obscenity in your statement make it a work of art on so many levels." - J. Jystad, 2001

                              S Offline
                              S Offline
                              Super Lloyd
                              wrote on last edited by
                              #37

                              Well it's only tip #237, so I guess it's not the 1st thing I should rush to do! :)

                              A train station is where the train stops. A bus station is where the bus stops. On my desk, I have a work station.... _________________________________________________________ My programs never have bugs, they just develop random features.

                              P D 2 Replies Last reply
                              0
                              • M Mechanical

                                Super Lloyd wrote:

                                any C# performance tip is welcome!

                                That is like looking for performance from Java: You won't get it. If you need (or want) performance, don't do retards' languages. I know this thread isn't meant to incite hatred against retards' languages.

                                NULL

                                D Offline
                                D Offline
                                Derek Viljoen
                                wrote on last edited by
                                #38

                                Mechanical, I checked your profile. You've never authored an article, posted a snippet, entered a blog post, or otherwise shared any original thought, except to snipe at other people's comments on the message boards. In other words, you have yet to provide any empirical evidence for your worth to this site. No be a good boy and go away, please.

                                M 1 Reply Last reply
                                0
                                • M Mechanical

                                  My statement was made because I had to maintain some Native code I wrote some years ago. I realized how retarded I had become doing retards' languages.

                                  peterchen wrote:

                                  Are you open to evidence for my statement

                                  I'm all ears (big, pointy ears).

                                  NULL

                                  P Offline
                                  P Offline
                                  peterchen
                                  wrote on last edited by
                                  #39

                                  The Raymond Chen vs. Rico Mariani competition comes to mind. Clickety[^] Clickety-Click[^] The final result, at first look, supports your statement: The C++ version completed before the .NET application even did load. However, when you look at the history and details, you see that the road to the superfast C++ application was a rocky one, introducing subtle bugs and requiring a very experienced developer to counter the rather simple improvements to the C# solution.


                                  With extensions like LINQ, Closures, Lambdas, Generics and some syntactic sugar, C# has become a rather complex and powerful language. It's complex and powerful in a different sense than C++, but still.

                                  Agh! Reality! My Archnemesis![^]
                                  | FoldWithUs! | sighist | WhoIncludes - Analyzing C++ include file hierarchy

                                  modified on Friday, November 5, 2010 11:17 AM

                                  1 Reply Last reply
                                  0
                                  • S Super Lloyd

                                    Well it's only tip #237, so I guess it's not the 1st thing I should rush to do! :)

                                    A train station is where the train stops. A bus station is where the bus stops. On my desk, I have a work station.... _________________________________________________________ My programs never have bugs, they just develop random features.

                                    P Offline
                                    P Offline
                                    peterchen
                                    wrote on last edited by
                                    #40

                                    Hey! Take stop reading my mind!

                                    Agh! Reality! My Archnemesis![^]
                                    | FoldWithUs! | sighist | WhoIncludes - Analyzing C++ include file hierarchy

                                    1 Reply Last reply
                                    0
                                    • D DaveAuld

                                      Nothing to do with the optimisation, but what about using the StopWatch class instead of datetime? Start the stop watch immediately before you enter the loop, and then stop it as soon as the loop exists.

                                      Dave Find Me On: Web|Facebook|Twitter|LinkedIn CPRepWatcher now available as Packaged Chrome Extension, visit my articles for link.

                                      L Offline
                                      L Offline
                                      Luc Pattyn
                                      wrote on last edited by
                                      #41

                                      I agree. On my machine 10 iterations take 0.5 milliseconds, which DateTime.Now can't catch at all. :)

                                      Luc Pattyn [Forum Guidelines] [Why QA sucks] [My Articles] Nil Volentibus Arduum

                                      Please use <PRE> tags for code snippets, they preserve indentation, and improve readability.

                                      1 Reply Last reply
                                      0
                                      • S Super Lloyd

                                        I already posted the source code: http://www.codeproject.com/Lounge.aspx?msg=3657380#xx3657380xx[^] As to the disassembly, err.... well, ok, but I have to cut the C++ version as it huge loads of stuff coming the #include(s), hopefully I'll cut it right ... disassembled JITted C#

                                        --- C:\Dev\Test\Performance\CSperf\Program.cs ----------------------------------
                                        if (args.Length != 1)
                                        00000000 push ebp
                                        00000001 mov ebp,esp
                                        00000003 push edi
                                        00000004 push esi
                                        00000005 sub esp,6Ch
                                        00000008 mov esi,ecx
                                        0000000a lea edi,[ebp-74h]
                                        0000000d mov ecx,1Bh
                                        00000012 xor eax,eax
                                        00000014 rep stos dword ptr es:[edi]
                                        00000016 mov ecx,esi
                                        00000018 mov dword ptr [ebp-0Ch],esp
                                        0000001b mov dword ptr [ebp-74h],2941BF9Bh
                                        00000022 mov dword ptr [ebp-60h],ecx
                                        00000025 cmp dword ptr ds:[001B7CB8h],0
                                        0000002c je 00000033
                                        0000002e call 62889E21
                                        00000033 xor edx,edx
                                        00000035 mov dword ptr [ebp-28h],edx
                                        00000038 xor edx,edx
                                        0000003a mov dword ptr [ebp-1Ch],edx
                                        0000003d xor edx,edx
                                        0000003f mov dword ptr [ebp-24h],edx
                                        00000042 xor edx,edx
                                        00000044 mov dword ptr [ebp-2Ch],edx
                                        00000047 xor edx,edx
                                        00000049 mov dword ptr [ebp-20h],edx
                                        0000004c xor edx,edx
                                        0000004e mov dword ptr [ebp-10h],edx
                                        00000051 mov eax,dword ptr [ebp-60h]
                                        00000054 cmp dword ptr [eax+4],1
                                        00000058 je 0000006B
                                        {
                                        Console.WriteLine("Usage:\tsieve [iterations]");
                                        0000005a mov ecx,dword ptr ds:[03832088h]
                                        00000060 call 62202DB4
                                        return;
                                        00000065 nop
                                        00000066 jmp 0000019A
                                        }

                                        		int NUM = int.Parse(args\[0\]);
                                        

                                        0000006b mov eax,dword ptr [ebp-60h]
                                        0000006e cmp dword ptr [eax+4],0
                                        00000072 ja 00000079
                                        00000074 call 6288BA5C
                                        00000079 mov ecx,dword ptr [eax+0Ch]
                                        0000007c call 6220EAC4
                                        00000081 mov dword ptr [ebp-38h],eax
                                        00000084 mov eax,dword ptr [ebp-38h]
                                        00000087 mov dword ptr [ebp-10h],eax
                                        var t0 = DateTime.Now;
                                        0000008a lea ecx,[ebp-40h]
                                        0000008d call 61D07768

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                                        Daniel Grunwald
                                        wrote on last edited by
                                        #42

                                        You need to be careful, the JIT will turn off optimizations when running inside the Visual Studio debugger (even in release builds!). To get the optimized JITted assembly code, you need to run your program from the command line, then attach the debugger to the running process, and click Break.

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                                        • S Super Lloyd

                                          yes, do post back please! :P

                                          A train station is where the train stops. A bus station is where the bus stops. On my desk, I have a work station.... _________________________________________________________ My programs never have bugs, they just develop random features.

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                                          Simon P Stevens
                                          wrote on last edited by
                                          #43

                                          Well I've written a C# version that runs 15-20% faster that your original on my PC. It doesn't use unsafe either. But I don't think you'll like it.

                                          private static void SafeTest_Improved1(string[] args)
                                          {
                                          int NUM = int.Parse(args[0]);
                                          int end = 8193;
                                          var primes = new byte[8193]{
                                          1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,
                                          1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,
                                          1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,
                                          1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,
                                          1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,
                                          1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,
                                          1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,
                                          1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,
                                          1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,
                                          1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,
                                          1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,
                                          1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,
                                          1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,
                                          1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,
                                          1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,
                                          1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,
                                          1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,
                                          1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,
                                          1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,
                                          1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,

                                              1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1
                                          
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