Search Results

Search found 4838 results on 194 pages for 'binary heap'.

Page 81/194 | < Previous Page | 77 78 79 80 81 82 83 84 85 86 87 88  | Next Page >

• setting up Ubuntu 10.10 as paravirtualized guest in Xen on RHEL5 host - what kernel?

  - by kostmo

  I've discovered the tool ubuntu-vm-builder, which I've installed and then invoked on an Ubuntu workstation as: sudo vmbuilder xen ubuntu --suite maverick --flavour virtual --arch amd64 --mem=512 --rootsize 8192 This workstation is not the intended target host of the virtual machine, however; I would like to host the guest on a Red Hat Enterprise Linux 5 machine that is running Xen 3.0.3. The output of this command appears to be a folder named ubuntu-xen containing three files: tmpXXXXXX, a very large file which I assume is the root partition image tmpYYYYYY, a somewhat large file which I assume is the swap partition image xen.conf, a text file I have copied the xen.conf file to the RHEL server's /etc/xen directory under the new name newvm, adjusting the paths of tempXXXXXX and tempYYYYYYin the file after also copying them from my local workstation to the RHEL server. When I launch the Virtual Machine Manager virt-manager, I can see the newvm virtual machine listed underneath the Dom0 machine. When I try to start newvm, I get the error: Error starting domain: virDomainCreate() failed POST operation failed: (xend.err 'Error creating domain: Kernel image does not exist: None') Indeed, there exists an entry kernel = 'None' in the xen.conf file. How do I find out what the path of the kernel should be? Is this path supposed to be to a kernel stored on the local filesystem of the RHEL5 host, or is it supposed to be a path inside the guest image? I see that the vmbuilder command provides for a --xen-kernel option, along with a --xen-ramdisk option, but I'm not sure what to use for either. I think I should be able to get this to work, since Ubuntu is said to be supported as a Xen guest, even though the Xen 4.0.1 docs state support for only a limited set of distributions, Ubuntu excluded. Update 1 When running vmbuilder on my local workstation, I did observe an output line saying: Calling hook: install_kernel and later, output lines saying: update-initramfs: Generating /boot/initrd.img-2.6.35-23-virtual [...] run-parts: executing /etc/kernel/postinst.d/initramfs-tools 2.6.35-23-virtual /boot/vmlinuz-2.6.35-23-virtual So in the xen.conf file, I tried setting the lines: kernel = '/boot/vmlinuz-2.6.35-23-virtual' ramdisk = '/boot/initrd.img-2.6.35-23-virtual' When trying to start the VM, I got an error similar to last time: Error starting domain: virDomainCreate() failed POST operation failed: (xend.err 'Error creating domain: Kernel image does not exist: /boot/vmlinuz-2.6.35-23-virtual') This makes me think that the RHEL5 machine is looking for local files, rather than a file within the binary guest disk image. After running sudo updatedb on my workstation, neither of those files were found. If the vmbuilder tool had tried to install them, it must have failed. Update 2 I was able to extract the kernel and initrd images from the guest disk binary by mounting it: mkdir mnt_tmp sudo mount ubuntu-xen/tmpXXXXXX mnt_tmp/ -o loop cp mnt_tmp/boot/vmlinuz-2.6.35-23-virtual virtual_kernel_ubuntu cp mnt_tmp/boot/initrd.img-2.6.35-23-virtual virtual_initrd_ubuntu These two files I copied to the RHEL5 server, and edited the xen.conf file to point to them as kernel and ramdisk. With this done, I could "run" the newvm virtual machine from within virt-manager, but was met with the message Console Not Configured For Guest when I double clicked the entry to open the Virtual Machine Console. As suggested by a forum, I then added the line vfb = [ 'type=vnc' ] to the configuration file, recreated the virtual machine (a ~10 min process), and this time got the message: Connecting to console for guest This remained indefinitely; after selecting View - Serial Console, I found a kernel panic: [5442621.272173] Kernel panic - not syncing: Attempted to kill the idle task! [5442621.272179] Pid: 0, comm: swapper Tainted: G D 2.6.35-23-virtual #41-Ubuntu [5442621.272184] Call Trace: [5442621.272191] [<ffffffff815a1b81>] panic+0x90/0x111 [5442621.272199] [<ffffffff810652ee>] do_exit+0x3be/0x3f0 [5442621.272204] [<ffffffff815a5e20>] oops_end+0xb0/0xf0 [5442621.272211] [<ffffffff8100ddeb>] die+0x5b/0x90 [5442621.272216] [<ffffffff815a56c4>] do_trap+0xc4/0x170 [5442621.272221] [<ffffffff8100ba35>] do_invalid_op+0x95/0xb0 [5442621.272227] [<ffffffff8130851c>] ? intel_idle+0xac/0x180 [5442621.272232] [<ffffffff810072bf>] ? xen_restore_fl_direct_end+0x0/0x1 [5442621.272239] [<ffffffff815a48fe>] ? _raw_spin_unlock_irqrestore+0x1e/0x30 [5442621.272247] [<ffffffff8108dfb7>] ? tick_broadcast_oneshot_control+0xc7/0x120 [5442621.272253] [<ffffffff8100ad5b>] invalid_op+0x1b/0x20 [5442621.272259] [<ffffffff8130851c>] ? intel_idle+0xac/0x180 [5442621.272264] [<ffffffff813084e0>] ? intel_idle+0x70/0x180 [5442621.272269] [<ffffffff810072bf>] ? xen_restore_fl_direct_end+0x0/0x1 [5442621.272275] [<ffffffff8148a147>] cpuidle_idle_call+0xa7/0x140 [5442621.272281] [<ffffffff81008d93>] cpu_idle+0xb3/0x110 [5442621.272286] [<ffffffff815873aa>] rest_init+0x8a/0x90 [5442621.272291] [<ffffffff81b04c9d>] start_kernel+0x387/0x390 [5442621.272297] [<ffffffff81b04341>] x86_64_start_reservations+0x12c/0x130 [5442621.272303] [<ffffffff81b08002>] xen_start_kernel+0x55d/0x561 Update 3 I tried an i386 architecture instead of amd64, but got the same kernel panic. Also, it seems the Virtual Machine Manager pays attention to the format of the filename of the kernel; for the same kernel binary, I tried simply naming it vmlinuz-virtual, which threw out an error box about an invalid kernel. When I named it vmlinuz-2.6.35-23-virtual, it did not throw the error, but it did still result in the kernel panic shortly thereafter.

  Read the article

• xerces-c: Xml parsing multiple files

  - by user459811

  I'm atempting to learn xerces-c and was following this tutorial online. http://www.yolinux.com/TUTORIALS/XML-Xerces-C.html I was able to get the tutorial to compile and run through a memory checker (valgrind) with no problems however when I made alterations to the program slightly, the memory checker returned some potential leak bytes. I only added a few extra lines to main to allow the program to read two files instead of one. int main() { string configFile="sample.xml"; // stat file. Get ambigious segfault otherwise. GetConfig appConfig; appConfig.readConfigFile(configFile); cout << "Application option A=" << appConfig.getOptionA() << endl; cout << "Application option B=" << appConfig.getOptionB() << endl; // Added code configFile = "sample1.xml"; appConfig.readConfigFile(configFile); cout << "Application option A=" << appConfig.getOptionA() << endl; cout << "Application option B=" << appConfig.getOptionB() << endl; return 0; } I was wondering why is it when I added the extra lines of code to read in another xml file, it would result in the following output? ==776== Using Valgrind-3.6.0 and LibVEX; rerun with -h for copyright info ==776== Command: ./a.out ==776== Application option A=10 Application option B=24 Application option A=30 Application option B=40 ==776== ==776== HEAP SUMMARY: ==776== in use at exit: 6 bytes in 2 blocks ==776== total heap usage: 4,031 allocs, 4,029 frees, 1,092,045 bytes allocated ==776== ==776== 3 bytes in 1 blocks are definitely lost in loss record 1 of 2 ==776== at 0x4C28B8C: operator new(unsigned long) (vg_replace_malloc.c:261) ==776== by 0x5225E9B: xercesc_3_1::MemoryManagerImpl::allocate(unsigned long) (MemoryManagerImpl.cpp:40) ==776== by 0x53006C8: xercesc_3_1::IconvGNULCPTranscoder::transcode(unsigned short const*, xercesc_3_1::MemoryManager*) (IconvGNUTransService.cpp:751) ==776== by 0x4038E7: GetConfig::readConfigFile(std::string&) (in /home/bonniehan/workspace/test/a.out) ==776== by 0x403B13: main (in /home/bonniehan/workspace/test/a.out) ==776== ==776== 3 bytes in 1 blocks are definitely lost in loss record 2 of 2 ==776== at 0x4C28B8C: operator new(unsigned long) (vg_replace_malloc.c:261) ==776== by 0x5225E9B: xercesc_3_1::MemoryManagerImpl::allocate(unsigned long) (MemoryManagerImpl.cpp:40) ==776== by 0x53006C8: xercesc_3_1::IconvGNULCPTranscoder::transcode(unsigned short const*, xercesc_3_1::MemoryManager*) (IconvGNUTransService.cpp:751) ==776== by 0x40393F: GetConfig::readConfigFile(std::string&) (in /home/bonniehan/workspace/test/a.out) ==776== by 0x403B13: main (in /home/bonniehan/workspace/test/a.out) ==776== ==776== LEAK SUMMARY: ==776== definitely lost: 6 bytes in 2 blocks ==776== indirectly lost: 0 bytes in 0 blocks ==776== possibly lost: 0 bytes in 0 blocks ==776== still reachable: 0 bytes in 0 blocks ==776== suppressed: 0 bytes in 0 blocks ==776== ==776== For counts of detected and suppressed errors, rerun with: -v ==776== ERROR SUMMARY: 2 errors from 2 contexts (suppressed: 2 from 2)

  Read the article

• Are there any good books to learn C++ if you already know Java and C#

  - by JF LR

  Hi, I would like to know if you have any good books that teach C++ programming without repeating basic stuff. In fact, I already well know Java and C#. I also have a basic knowledge in C and assembly, so I understand a little bit pointer arithmetic, manual memory management and heap based allocation. I was looking at O'Reilly's C++ in a Nutshell and was also wondering if this book would be a good choice. Thank you

  Read the article

• Using GA in GUI

  - by AlexT

  Sorry if this isn't clear as I'm writing this on a mobile device and I'm trying to make it quick. I've written a basic Genetic Algorithm with a binary encoding (genes) that builds a fitness value and evolves through several iterations using tournament selection, mutation and crossover. As a basic command-line example it seems to work. The problem I've got is with applying a genetic algorithm within a GUI as I am writing a maze-solving program that uses the GA to find a method through a maze. How do I turn my random binary encoded genes and fitness function (add all the binary values together) into a method to control a bot around a maze? I have built a basic GUI in Java consisting of a maze of labels (like a grid) with the available routes being in blue and the walls being in black. To reiterate my GA performs well and contains what any typical GA would (fitness method, get and set population, selection, crossover, etc) but now I need to plug it into a GUI to get my maze running. What needs to go where in order to get a bot that can move in different directions depending on what the GA says? Rough pseudocode would be great if possible As requested, an Individual is built using a separate class (Indiv), with all the main work being done in a Pop class. When a new individual is instantiated an array of ints represent the genes of said individual, with the genes being picked at random from a number between 0 and 1. The fitness function merely adds together the value of these genes and in the Pop class handles selection, mutation and crossover of two selected individuals. There's not much else to it, the command line program just shows evolution over n generations with the total fitness improving over each iteration. EDIT: It's starting to make a bit more sense now, although there are a few things that are bugging me... As Adamski has suggested I want to create an "Agent" with the options shown below. The problem I have is where the random bit string comes into play here. The agent knows where the walls are and has it laid out in a 4 bit string (i.e. 0111), but how does this affect the random 32 bit string? (i.e. 10001011011001001010011011010101) If I have the following maze (x is the start place, 2 is the goal, 1 is the wall): x 1 1 1 1 0 0 1 0 0 1 0 0 0 2 If I turn left I'm facing the wrong way and the agent will move completely off the maze if it moves forward. I assume that the first generation of the string will be completely random and it will evolve as the fitness grows but I don't get how the string will work within a maze. So, to get this straight... The fitness is the result of when the agent is able to move and is by a wall. The genes are a string of 32 bits, split into 16 sets of 2 bits to show the available actions and for the robot to move the two bits need to be passed with four bits from the agent showings its position near the walls. If the move is to go past a wall the move isn't made and it is deemed invalid and if the move is made and if a new wall is found then the fitness goes up. Is that right?

  Read the article

• Is the stack garbage collected in Java?

  - by girinie

  The heap memory is garbage collected in Java. Is the stack garbage collected as well? How is stack memory reclaimed?

  Read the article

• when does static member gets memory.

  - by vaibhav

  I have a class which have a static member. As I understand all static members are common for all instance of the class. So it means static members would get memory only once. Where is this memory is allocated (Stack or Heap) and when this memory get allocated.

  Read the article

• How to combine ASCII text files, then encrypt, then decrypt, and put into a 'File' Class? C++

  - by Joel

  For example, if I have three ASCII files: file1.txt file2.txt file3.txt ...and I wanted to combine them into one encrypted file: database.txt Then in the application I would decrypt the database.txt and put each of the original files into a 'File' class on the heap: class File{ public: string getContents(); void setContents(string data); private: string m_data; }; Is there some way to do this? Thanks

  Read the article

• Is it possible to use Boehm garbage collector only for the part of the program?

  - by bialix

  I've read article in LinuxJournal about Boehm-Demers-Weiser garbage collector library. I'm interesting to use it in my library instead of my own reference counting implementation. I have only one question: is it possible to use gc only for my shared library and still use malloc/free in the main application? I'm not quite understand how gc checks the heap so I'm worrying about performance of gc in that case and possible side effects.

  Read the article

• How does JVM handles dynamic allocation

  - by Nile

  I want to understand how JVM manages heap for the dynamic allocations. Since every java program is invoked as a thread, when does JVM's garbage collector come into play. Also, how things work for javascript's dynamic allocation ?

  Read the article

• Why does GC not clear the Dialog references?

  - by Pavel

  I have a dialog. Every time I create it and then dispose, it stays in memory. It seems to be a memory leak somewhere, but I can't figure it out. Do you have any ideas? See the screenshot of heap dump for more information. Thanks in advance. http://img441.imageshack.us/img441/5764/leak.png

  Read the article

• Memory randomization as application security enhancement?

  - by Paul Sasik

  I recently came upon a Microsoft article that touted new "defensive enhancements" of Windows 7. Specifically: Address space layout randomization (ASLR) Heap randomization Stack randomization The article went on to say that "...some of these defenses are in the core operating system, and the Microsoft Visual C++ compiler offers others" but didn't explain how these strategies would actually increase security. Anyone know why memory randomization increases security, if at all? Do other platforms and compilers employ similar strategies?

  Read the article

• How does the garbage collector determine whether an object is garbage?

  - by n0vic3c0d3r

  How does the garbage collector determine whether an object is garbage? Does it refer to the stack to check the references to the space allocated in the heap?

  Read the article

• What is the most efficient way to learn x86 assembly?

  - by Web Des

  I want to learn x86 assembly and I want to know if learning reverse engineering is a good way to learn it? Also I have some c++ knowledge of pointers, stack, heap , references, etc.. I was considering this book. http://www.amazon.com/Reversing-Secrets-Engineering-Eldad-Eilam/dp/0764574817/ref=sr_1_1?s=books&ie=UTF8&qid=1340420512&sr=1-1&keywords=reverse+engineering Also Is reverse engineering the same as what they call disassembly?

  Read the article

• Visual C++: Invalid allocation size. How to force the debugger to stop on this message?

  - by James Roth

  The MFC program I am debugging is printing this message in the "Output" window in Visual Studio 9.0: HEAP[AppName.exe]: Invalid allocation size - 99999998 (exceeded 7ffdefff) I'm pretty sure this is due to a bad "new", uninitialized variable or similar error. The question is: how do I get the debugger to stop on this message so that I can view the stack trace and solve the problem?

  Read the article

• Does variable = null set it for garbage collection

  - by manyxcxi

  Help me settle a dispute with a coworker: Does setting a variable or collection to null in Java aid in garbage collection and reducing memory usage? If I have a long running program and each function may be iteratively called (potentially thousands of times): Does setting all the variables in it to null before returning a value to the parent function help reduce heap size/memory usage?

  Read the article

• Free JVM profilers for websites

  - by 2Real

  I'm looking for a JVM profiler (preferably open source) so I can look at the heap and cpu usage of my personal website. I've used Lambda Probe, and I like it because it provides a web interface for my remote Unix computer that has no display. I was wondering what else is available Thanks,

  Read the article

• some qeustions about Vector in STL

  - by skydoor

  I have some questions about vector in STL to clarify..... 1 Where are the objects in vector allocated? heap? 2 does vector have boundary check? If the index out of the boundary, what error will happen? 3 Why array is faster than vector? 4 Is there any case in which vector is not applicable but array is a must?

  Read the article

• How many registers in custom VM?

  - by DeadMG

  I'm designing a custom VM and am curious about how many registers I should use. Initially, I had 255, but I'm a little concerned about backing 255 pointers (a whole KB) on to the stack or heap every time I call a function, when most of them won't even be used. How many registers should I use?

  Read the article

• C++ segmentation error when first parameter is null in comparison operator overload

  - by user1774515

  I am writing a class called Word, that handles a c string and overloads the <, , <=, = operators. word.h: friend bool operator<(const Word &a, const Word &b); word.cc: bool operator<(const Word &a, const Word &b) { if(a == NULL && b == NULL) return false; if(a == NULL) return true; if(b == NULL) return false; return a.wd < b.wd; //wd is a valid c string } main: char* temp = NULL; //EDIT: i was mistaken, temp is a char pointer Word a("blah"); //a.wd = [b,l,a,h] cout << (temp<a); i get a segmentation error before the first line of the operator< method after the last line in the main. I can correct the problem by writing cout << (a>temp); where the operator> is similarly defined and i get no errors. but my assignment requires (temp < a) to work so this is where i ask for help. EDIT: i made a mistake the first time and i said temp was of type Word, but it is actually of type char*. so i assume that the compiler converts temp to a Word using one of my constructors. i dont know which one it would use and why this would work since the first parameter is not Word. here is the constructor i think is being used to make the Word using temp: Word::Word(char* c, char* delimeters=NULL) { char *temporary = "\0"; if(c == NULL) c = temporary; check(stoppers!=NULL, "(Word(char*,char*))NULL pointer"); //exits the program if the expression is false if(strlen(c) == 0) size = DEFAULT_SIZE; //10 else size = strlen(c) + 1 + DEFAULT_SIZE; wd = new char[size]; check(wd!=NULL, "Word(char*,char*))heap overflow"); delimiters = new char[strlen(stoppers) + 1]; //EDIT: changed to [] check(delimiters!=NULL,"Word(char*,char*))heap overflow"); strcpy(wd,c); strcpy(delimiters,stoppers); count = strlen(wd); } wd is of type char* thanks for looking at this big question and trying to help. let me know if you need more code to look at

  Read the article

• Question regarding the method local innerclasses accesing the local variables of the method

  - by flash

  Hi I was going through the SCJP book about the innerclasses, and found this statement, it goes something like this. "A method local class can only refer to the local variables which are marked final" and in the explanation the reason specified is about the scope and lifetime of the local class object and the local variables on the heap, But I am unable to understand that.am I missing anything here about 'final'??

  Read the article

• .NET object creation and generations

  - by nimoraca

  Is there a way to tell the .NET to allocate a new object in generation 2 heap. I have a problem where I need to allocate approximately 200 MB of objects, do something with them, and throw them away. What happens here is that all the data gets copied two times (from gen0 to gen1 and then from gen1 to gen2).

  Read the article

• Using operator+ without leaking memory?

  - by xokmzxoo

  So the code in question is this: const String String::operator+ (const String& rhs) { String tmp; tmp.Set(this->mString); tmp.Append(rhs.mString); return tmp; } This of course places the String on the stack and it gets removed and returns garbage. And placing it on the heap would leak memory. So how should I do this?

  Read the article

• Details to log when starting an application

  - by Karl

  To help support and anyone who may use one of my applications I tend to log a few things during the application startup. Currently I log: Start Time App Name App Author App Version App Classpath Current working directory Java vendor Java version Max heap size Taking into consideration this application may be used / supported by a whole host of people can anyone think of any other vital details which we / others should log for good practice?

  Read the article

• Best way to laod a large file into arraylist in java

  - by user1730833

  I have a file whose size is about 300mb i want to read the contents line by line and then add it into arraylist. So i have made an object of array list a1 , then reading the file using bufferedreader , after that when i add the lines from file into arraylist it gives an error Exception in thread "main" java.lang.OutOfMemoryError: Java heap space. Please tell me what should be the solution for this.

  Read the article

• Java GC: top object classes promoted (by size)?

  - by Java Geek

  Hello! Please let me know what is the best way to determine composition of young generation memory promoted to old generation, after each young GC event? Ideally I would like to know class names which are responsible say, for 80% of heap in each "young gen - old gen" promotion chunk; Example: I have 600M young gen, each tenure promotes 6M; I want to know which objects compose this 6M. Thank you.

  Read the article

< Previous Page | 77 78 79 80 81 82 83 84 85 86 87 88  | Next Page >