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Experts - help - Memory Allocation with disabling paging / swapping oren frenkel16-Dec-03 4:37 oren frenkel 16-Dec-03 4:37  Hi, I need to allocate memory for a large buffer (between 1 to 100 MB) in the RAM for a relatively short period (for recording data in an extremely high rate from USB2). The problem is that i need to force the operating system NOT TO USE SWAPPING / PAGING on that buffer. This means that the whole buffer must be physically allocated in the RAM, and NOT in the hard disk. does anybody know how to do that? Programming language: C++ OS : windows 2000/xp Tanks, Oren. Re: Experts - help - Memory Allocation with disabling paging / swapping Felix Gartsman16-Dec-03 5:31 Felix Gartsman 16-Dec-03 5:31  Use VirtualLock, but you'll need to call SetProcessWorkingSetSize first to reserve so large buffer. A few problems though: you may not always get such large buffer, and if you get your machine will not run other programs nicely. Also you need admin or equivalent rights to call SetProcessWorkingSetSize. Re: Experts - help - Memory Allocation with disabling paging / swapping oren frenkel16-Dec-03 5:44 oren frenkel 16-Dec-03 5:44  Felix, Thanks! I have just finished reading about these functions in the MSDN (the trick is to find them), and then I received your mail. So, Thanks anyway! Another small question: the SetProcessWorkingSetSize function accepts the process's handle, and the arguments dwMaximumWorkingSetSize dwMinimumWorkingSetSize. In what units are the last 2 arguments presented (bytes, or number of pages) ? if they represent number of pages, how do I get the size of each page in bytes? Regards, Oren. Re: Experts - help - Memory Allocation with disabling paging / swapping Felix Gartsman16-Dec-03 7:39 Felix Gartsman 16-Dec-03 7:39  oren frenkel wrote: In what units are the last 2 arguments presented (bytes, or number of pages) ? if they represent number of pages, how do I get the size of each page in bytes? From memory - bytes. To get page size use GetSystemInfo. Re: Experts - help - Memory Allocation with disabling paging / swapping oren frenkel16-Dec-03 22:40 oren frenkel 16-Dec-03 22:40  Thanks again! Re: Experts - help - Memory Allocation with disabling paging / swapping John M. Drescher16-Dec-03 7:56 John M. Drescher 16-Dec-03 7:56  Also do not let the application minimize. Windows will reduce the workingset to 2MB if the application is minimized. John Re: Experts - help - Memory Allocation with disabling paging / swapping oren frenkel16-Dec-03 22:38 oren frenkel 16-Dec-03 22:38  Thank you very much! This is the exact kind of tip that i cannot get in the MSDN. By the way - if the window is in the background (not in focus - another application is in focus) - does the same thing happen? Does it also happen when the computer is being locked, or when in idle for a long time (for instance - the user starts recording data in a cyclic buffer, and leaves the computer idle for 30 minutes). More important - if i set the working set to 64 MB, and allocated a 64 MB buffer and locked it, and only AFTERWARDS the user minimizes the window - does this also happen? regards, Oren. Re: Experts - help - Memory Allocation with disabling paging / swapping John M. Drescher17-Dec-03 4:11 John M. Drescher 17-Dec-03 4:11  oren frenkel wrote: This is the exact kind of tip that i cannot get in the MSDN. I found this out the hard way. I have an application that digitizes mamograms. A case of 4 images can be as much as 256MB. The digitizer only has a buffer to hold about 1/2 of an image so if you don't read the data in a 20 to 30 second period it will overflow. Well if the user pressed the minimize button the whole application thrashed for atleast that time and we got an overflow of the buffer and the pc had 512 MB of memory with almost atleast 150MB free. This was tested on NT4 and I believe Win2k but I have not tested it recently. Anyways this was because when the application minimizes the working set is trimmed. I did verify that was indeed what was happening on these operating systems. oren frenkel wrote: if the window is in the background (not in focus - another application is in focus) - does the same thing happen? No. Only when the application is minimized. My solution was to not let the application minimize only during digitization. oren frenkel wrote: More important - if i set the working set to 64 MB, and allocated a 64 MB buffer and locked it, and only AFTERWARDS the user minimizes the window - does this also happen? Yes. It would happen there too. John Re: Experts - help - Memory Allocation with disabling paging / swapping oren frenkel17-Dec-03 4:18 oren frenkel 17-Dec-03 4:18  John - thanks for your time and effort! Since my application has to record data in an extremely high speed from USB 2 (only graphics are the progress bar and status window) - I migh bypass the problem by running the engine on a different process (it now runs on a different thread). At the worst case - I will not enable the user to minimize the window during recording. Thanks again, Oren. Re: Experts - help - Memory Allocation with disabling paging / swapping John M. Drescher17-Dec-03 4:27 John M. Drescher 17-Dec-03 4:27  oren frenkel wrote: I migh bypass the problem by running the engine on a different process (it now runs on a different thread). If you run it in a service or other application that does not have a window you will not experience this problem. John Starter neo2k316-Dec-03 3:58 neo2k3 16-Dec-03 3:58  Hello everybody, I'm new to the entire world of microsoft technologies . Can anyone suggest a start up? the right book...to start my journey to Programming in windows environment VC++/COM/ATL/.NET....I know C,C++. bye, East Re: Starter valikac16-Dec-03 5:11 valikac 16-Dec-03 5:11  What do you want to use MFC or raw win32 API? MFC: Introduction to MFC Programming with Visual C++ by Richard M. Jones Programming Windows With MFC by Jeff Prosise Win32 API: Programming Windows by Charles Petzold COM/ATL: Inside COM (Programming Series) by Dale Rogerson Developer's Workshop to COM and ATL 3.0 by Andrew Troelsen Kuphryn Re: Starter Anonymous17-Dec-03 3:26 Anonymous 17-Dec-03 3:26  Thanks for ur intrest...I will try to explain the problem...i happen to come across.... codes in VC++ environment with strange looking macros...concepts like dll,and others not a part of core c++....i'm not sure they are there for winAPI or vc++ concept....i'm facing all kinds of microsoft technologies as com/mfc/atl/.net all of a sudden.. ..i don't know where to start learning and how to proceed.... Re: Starter LittleYellowBird16-Dec-03 5:16 LittleYellowBird 16-Dec-03 5:16  Hi, I'm no expert on VC++ but the books I've found most usefull are 'Practical C++ 6' By Bates & Tompkins (this has some nice example to get you started and some detail too. And 'Programming Windows with MFC' by Jeff Prosise, this is my main reference and if I could only have one book on VC++ this would be it. It gives you lots of detail and explains things really well. (I've just thought - I am using VC++ 6 which is fairly old now, anyway they are the books I use what I use for what its worth.) If you already know C++ then you've got a good start Good luck Ali Re: Starter Roger Wright16-Dec-03 5:23 Roger Wright 16-Dec-03 5:23  Alison Pentland wrote: 'Programming Windows with MFC' by Jeff Prosise I guess this has been updated since I bought my copy of Programming Windows95 with MFC. "Another day done - All targets met; all systems fully operational; all customers satisfied; all staff keen and well motivated; all pigs fed and ready to fly" - Jennie A. Re: Starter BaldwinMartin16-Dec-03 11:19 BaldwinMartin 16-Dec-03 11:19  Don't forget Dennis Ritchie Best Wishes and Happy Holiday's, ez_way HEAP[MyProgram.exe]: Invalid Address specified to RtlSizeHeap( 00140000, 001E8D10 ) UOzkan16-Dec-03 3:02 UOzkan 16-Dec-03 3:02  Hi everyone, In my code while debugging, after user breakpoint is called after this line pops up in debug output line. I have some doubts that this may be happened by not cleaning a _bstr_t type variable. How do i allocate and free this type of variable? Thank you very much. Ugur Ozkan Re: HEAP[MyProgram.exe]: Invalid Address specified to RtlSizeHeap( 00140000, 001E8D10 ) Abebe16-Dec-03 3:38 Abebe 16-Dec-03 3:38  well...that's kinda of the advantage of _bstr_t, you shouldn't have to allocate or free memory, because it does that all for you. Er zit een korstje op mijn aars. Re: HEAP[MyProgram.exe]: Invalid Address specified to RtlSizeHeap( 00140000, 001E8D10 ) John M. Drescher16-Dec-03 7:58 John M. Drescher 16-Dec-03 7:58  UOzkan wrote: free this type of variable? Let it go out of scope or set it to NULL. John MATLAB C++ problems, help~! Vincent Sim16-Dec-03 3:01 Vincent Sim 16-Dec-03 3:01  hi everybody, i am facing some matlab c++ problems. i am looking for some solutions for them. anybody can help me? thank you very much. p/s: thank you Jwood for your information. Problem 1: MATLAB SOURCE CODE: [features, targets] = improved_DA1(x, [cluster,0.95]); MATLAB C++ CONVERSION: mwArray cluster ; improved_DA(x, empty(cluster,0.95)); after compiling,…… D:\others\im\me.cpp(116) : error C2660: 'empty' : function does not take 2 parameters Problem 2: MATLAB C++ CONVERSION: I3=uint8(I2); After compiling,……. D:\others\im\me.cpp(137) : error C2065: 'uint8' : undeclared identifier Problem 3: MATLAB SOURCE CODE: Smu=zeros(1,Nmu); for i=1:Ncent, Smu(i) = sum(std(train_features(:,find(label == i))')); MATLAB C++ CONVERSION: Smu = zeros(1,Nmu); for (i = 1 ; i<=Ncent ; i++) { /*232*/ Smu(i) = sum(std(train_features(:,find(label == i))')); } after compiling,….. D:\others\im\me.cpp(232) : error C2001: newline in constant Problem 4: MATLAB C++: …………… double Tmin; mwArray T; Nmu = params(1); epsi = params(2); /*167*/ T= 3*max(eig(cov(train_features',1)')); //Initial temperature Tmin = 0.01; …………. After compiling……. D:\others\im\me.cpp(167) : fatal error C1057: unexpected end of file in macro expansion vincent sim CTabCtrl - An Introduction to... Jock197916-Dec-03 2:17 Jock1979 16-Dec-03 2:17  Hi all, Wondering if someone could point me in the right direction for a very basic tutorial for using Tab Controls in Visual C++. Been struggling to implement my own for a while now... Thanks in advance Re: CTabCtrl - An Introduction to... Abebe16-Dec-03 3:40 Abebe 16-Dec-03 3:40  try searching this site and it'll give enough info to get you started. Er zit een korstje op mijn aars. error C2065: 'DDX_Time' : undeclared identifier Neha16-Dec-03 0:32 Neha 16-Dec-03 0:32  Hi, I am trying compile a source code, now i am getting this error: error C2065: 'DDX_Time' : undeclared identifier I am using VC++6.0. Could any one tell me why is it so? Regards Neha Re: error C2065: 'DDX_Time' : undeclared identifier Michael P Butler16-Dec-03 0:44 Michael P Butler 16-Dec-03 0:44  Neha wrote: error C2065: 'DDX_Time' : undeclared identifier DDX_Time isn't part of the standard MFC DDX. It may be a custom type, have you included the correct header files. MSDN refers to DDX_Time as part of the possible User extensions but doesn't give a full implementation. Michael Snow is lying on the ground, and in the air the sleigh bells sound, The frosted patterned window panes, it's British summer time again. No, it's not, It's Christmas - Santa Claus in on the Dole (Spitting Image 1986) Where can i get specification for GDI+ images encoders/decoders? YuriSp16-Dec-03 0:04 YuriSp 16-Dec-03 0:04  Where can i get specification for GDI+ images encoders/decoders?

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