Search Results

Search found 18464 results on 739 pages for 'virtual functions'.

Page 139/739 | < Previous Page | 135 136 137 138 139 140 141 142 143 144 145 146  | Next Page >

  • Is it good practice to use functions just to centralize common code?

    - by EpsilonVector
    I run across this problem a lot. For example, I currently write a read function and a write function, and they both check if buf is a NULL pointer and that the mode variable is within certain boundaries. This is code duplication. This can be solved by moving it into its own function. But should I? This will be a pretty anemic function (doesn't do much), rather localized (so not general purpose), and doesn't stand well on its own (can't figure out what you need it for unless you see where it is used). Another option is to use a macro, but I want to talk about functions in this post. So, should you use a function for something like this? What are the pros and cons?

    Read the article

  • memory available to 64bit Fedora guest under 32bit XP host running virtualbox

    - by Chris Card
    I have successfully installed a 64 bit Fedora 11 guest os using VirtualBox on a host machine (AMD64) running 32 bit Windows XP . At the moment the host machine has 2 Gb ram installed and I've allocated 1 Gb to the guest, which all works well. The host machine can hold a maximum of 4 Gb ram, so I was wondering if it's worth buying an extra 2 Gb for it. I know that 32 bit Windows XP can't use all of the 4 Gb, but can the guest os use any of the ram that the host os can't use?

    Read the article

  • WITH_OBJECT_HEADERS enabled GC from Dalvik?

    - by Wonil
    Hello, As I know Dalvik VM does not support generational GC as default. But, I found "WITH_OBJECT_HEADERS" compilation flag which could be related with generational GC from HeapInternal.h file. typedef struct DvmHeapChunk { #if WITH_OBJECT_HEADERS u4 header; const Object *parent; const Object *parentOld; const Object *markFinger; const Object *markFingerOld; u2 birthGeneration; u2 markCount; u2 scanCount; u2 oldMarkGeneration; u2 markGeneration; u2 oldScanGeneration; u2 scanGeneration; #endif Does anyone try to build Dalvik with this option enabled? Do you know anything about generational GC support from Dalvik? Regards, Wonil.

    Read the article

  • How can I get read-ahead bytes?

    - by Bruno Martinez
    Operating systems read from disk more than what a program actually requests, because a program is likely to need nearby information in the future. In my application, when I fetch an item from disk, I would like to show an interval of information around the element. There's a trade off between how much information I request and show, and speed. However, since the OS already reads more than what I requested, accessing these bytes already in memory is free. What API can I use to find out what's in the OS caches? Alternatively, I could use memory mapped files. In that case, the problem reduces to finding out whether a page is swapped to disk or not. Can this be done in any common OS?

    Read the article

  • Understanding Virtualization

    - by mohit
    Hi, I wana to know about Virtualization in detail. But start from basics, like what is virtualization, with real world examples and scenarios. When ever i search, i got Virtualization technologies, but i want to learn and in fcat know what exactly is virtualization, its types n all..... Please help me in getting practical details of term "Virtualization"

    Read the article

  • Of which bad practice is require calling functions in order a sign?

    - by stijn
    Sometimes I find myself writing comments on class methods like this: class A : public Base { public: /** * Sets variable; * should be called before ImplementsInterfaceMtehod(), * else has no effect. */ void SetSomeVariable( var_type value ); virtual void ImplementsInterfaceMethod(); } The callers of Base::ImplementsInterfaceMethod obviously do not know about the variable, and should not. But the users of A should set the variable if they want it to take effect. It is not required to set the variable (else it could be a parameter for the constructor), so I cannot throw exceptions in ImplementsInterfaceMethod if it is not set. Is this a sign of some typical bad practice? Is there a better way than writing a comment as shown to deal with this?

    Read the article

  • How to reliably measure available memory in Linux?

    - by Alex B
    Linux /proc/meminfo shows a number of memory usage statistics. MemTotal: 4040732 kB MemFree: 23160 kB Buffers: 163340 kB Cached: 3707080 kB SwapCached: 0 kB Active: 1129324 kB Inactive: 2762912 kB There is quite a bit of overlap between them. For example, as far as I understand, there can be active page cache (belongs to "cached" and "active") and inactive page cache ("inactive" + "cached"). What I want to do is to measure "free" memory, but in a way that it includes used pages that are likely to be dropped without a significant impact on overall system's performance. At first, I was inclined to use "free" + "inactive", but Linux's "free" utility uses "free" + "cached" in its "buffer-adjusted" display, so I am curious what a better approach is. When the kernel runs out of memory, what is the priority of pages to drop and what is the more appropriate metric to measure available memory?

    Read the article

  • git can I speed up committing?

    - by AndreasT
    I have a big repository in a shared folder. I use git from within a VM on that folder. Everything works nice, but the repository is big and git's searching through all directories and files when committing is slow. I cannot move this repository out of the shared folder. I tried to git add specific files and directories, but when I do git commit -m "something" it still goes off onto it's oddyssey through the directory tree. Can I do commits that ignore the rest of the tree?

    Read the article

  • How do polymorphic inline caches work with mutable types?

    - by kingkilr
    A polymorphic inline cache works by caching the actual method by the type of the object, in order to avoid the expensive lookup procedures (usually a hashtable lookup). How does one handle the type comparison if the type objects are mutable (i.e. the method might be monkey patched into something different at run time). The one idea I've come up with would be a "class counter" that gets incremented each time a method is adjusted, however this seems like it would be exceptionally expensive in a heavily monkey patched environ since it would kill all the PICs for that class, even if the methods for them weren't altered. I'm sure there must be a good solution to this, as this issue is directly applicable to Javascript and AFAIK all 3 of the big JS VMs have PICs (wow acronym ahoy).

    Read the article

  • Why are so many new languages written for the Java VM?

    - by sdudo
    There are more and more programming languages (Scala, Clojure,...) coming out that are made for the Java VM and are therefore compatible with the Java Byte-Code. I'm beginning to ask myself: Why the Java VM? What makes it so powerful or popular that there are new programming languages, which seem gaining popularity too, created for it? Why don't they write a new VM for a new language?

    Read the article

  • Prevent mapping all public members of a class in Fluent NHibernate

    - by alimbada
    I have a class generated from a WSDL that has a bunch of public properties and a public event. I'm extending this class with my own and adding some properties to it. All of my own properties are declared virtual, but the base class properties are not virtual. I'm using Fluent NHibernate's ClassMap to map only the properties from my extended class. How do I prevent (Fluent)NHibernate from trying to persist all the base class's public members? At the moment, I get the following exception when creating the ISessionFactory: NHibernate.InvalidProxyTypeException: The following types may not be used as proxies: Type: method get_<BaseClassProperty should be 'public/protected virtual' or 'protected internal virtual' Type: method set_<BaseClassProperty should be 'public/protected virtual' or 'protected internal virtual' ... Type: method add_<BaseClassEvent should be 'public/protected virtual' or 'protected internal virtual' Type: method remove_<BaseClassEvent should be 'public/protected virtual' or 'protected internal virtual'

    Read the article

  • How communicate with pty via minicom or screen?

    - by gscott2112
    I am trying to provide an AT/Modem-like interface around some hardware. Follwing this post I have the server setting up a pty using openpty(). Now I can communicate with the server as expected with a client app that open the slave and communicates via read() and write() calls. However I would also like to be able to use either the screen command or minicom to issue commands by hand to the slave. However the server never seems to receive any data when trying to do this. Is there something significant I am missing with this approach?

    Read the article

  • Php code works on guest os but doesn't work on host os

    - by Ieyasu Sawada
    Can you give me some guide on how to determine whats the problem if the same piece of code works on guest os. And doesn't work on the host os? I've created the project on Windows 7 but now it seems to be working on XP only. Here's what I have installed on the host os(Windows 7): And here's what I got on the guest os: And here's the screenshot. The guest os and host os side by side: Other things which are the same: php version mysql version apache same data stored on the database Here's the code of checkout.php: http://cu.pastebin.com/YeBR9rTs Forgive me if its messy.

    Read the article

  • How do I set up for sharing code (ASP.NET) across multiple domain names?

    - by Scott J.
    I have built a website and now the customer wants to split it between three different domains. What is the best way to do this? This is what I have so far. c:/website1/ points to www.website1.com c:/website1/vd1/ points to www.website2.com c:/website1/vd2/ points to www.website3.com The webhost I'm working with has done it the following way, but now I'm getting a bunch of errors that seems like it's not seeing the App_code folder. Do I need to make a lot of changes? How does this affect the location references?

    Read the article

  • Adding web reference is not generating the expected reference.cs file. Absent functions.

    - by user48408
    I'm working with an old windows app in visual studio 2005. A webserviced referenced in the original app has 2 functions and when i peak inside the auto-generated reference.cs file I notice a couple of other functions to allow async calls have been geenrated i.e. BeginWhateverFunctionNameIsCalled and EndWhateverFunctionNameIsCalled. My problem is that I've created a new windows app and added the same web references but the Begin and End functions are not generated in my reference.cs proxy class. Anyone know whats going on?

    Read the article

  • Would it be simply better to use the system's functions rather than use the language?

    - by Nullw0rm
    There are many scenarios where I've questioned PHP's performance with some of its functions, and whether I should build a complex class to handle specific things using its seemingly slow tools. For example, Complex regular expressions with sed and processing with awk would seemingly be exponential in performance rather than making PHP's regular expression and seemingly excessive functions parse and in time manage to finish it. If I were to do a lot of network tasks such as MX lookups/DIGging/retrieving simultaneously I would rather pass it via system() and let the OS handle it itself. There are simply too many functions in PHP, that are inefficient and result in slow pages or can be handled easier by the OS. What are your opinions? Do you think I should do the hard work with the OS in its own/custom functions?

    Read the article

  • In what circumstances can large pages produce a speedup ?

    - by timday
    Modern x86 CPUs have the ability to support larger page sizes than the legacy 4K (ie 2MB or 4MB), and there are OS facilities (Linux, Windows) to access this functionality. The Microsoft link above states large pages "increase the efficiency of the translation buffer, which can increase performance for frequently accessed memory". Which isn't very helpful in predicting whether large pages will improve any given situation. I'm interested in concrete, preferably quantified, examples of where moving some program logic (or a whole application) to use huge pages has resulted in some performance improvement. Anyone got any success stories ? There's one particular case I know of myself: using huge pages can dramatically reduce the time needed to fork a large process (presumably as the number of TLB records needing copying is reduced by a factor on the order of 1000). I'm interested in whether huge pages can also benefit more mundane applications though.

    Read the article

  • How to shrink Windows 7 XP Mode VHD files?

    - by A_M
    I'm trying to shrink a Windows 7 XP Mode VHD file with VhdResizer with little success. When I select my VHD file, it says "VhdExpand only supports fixed and dynamic VHD files". My XP Mode VHDs are dynamic files. Does anyone have any idea why it is failing? Failing that, does anyone have a process that I can use to shrink my XP mode VHD files on Windows 7 (64 bit)?

    Read the article

< Previous Page | 135 136 137 138 139 140 141 142 143 144 145 146  | Next Page >