Search Results

Search found 18119 results on 725 pages for 'shared memory'.

Page 252/725 | < Previous Page | 248 249 250 251 252 253 254 255 256 257 258 259  | Next Page >

  • Can someone explain the true landscape of Rails vs PHP deployment, particularly within the context of Reseller-based web hosting (e.g., Hostgator)?

    - by rcd
    Currently, I have a reseller account with the company HostGator. I design websites, which up until now have occasionally been wrapped in Wordpress CMSs and the like (PHP applications). I then sell hosting (of the site I've designed) to the client, which is pretty simple, in that I can simply click a button and add a new shared hosting account/site with whatever settings I want. Furthermore, I then utilize WHMCS to automate billing and account management. It's a nice package and pretty simple. I pay something like $25 a month, and can sell a hundred accounts under this (because my clients bandwidth requirements are low). Now I am finding the need to develop more customized applications, including a minimalist CMS and several proprietary things. I soon anticipate developing these apps for clients as well. Thus, I've spent the past few months learning Rails, and it's coming along well now. The thing that has nagged at me all along, though, is the deployment issue. I can't wrap my brain around it. It seems like all of the popular options (Heroku, etc) have nice automation with git and are set up in the "Rails Way". I get that (sort of). But it's terribly expensive... a single dyno, a helper, and the cheapest database (which they say is mainly suitable for testing) that isn't limited to 5MB runs $51. This is for ONE app!!! Throw in a "production" DB and you're over $200. This is like... the same prices as getting a server somewhere, right? Meanwhile, going back to what I guess is a "traditional" hosting environment with Hostgator, their server only has Ruby 1.8.7 and Rails 2.3.5... No Rails 3. AND, no Passenger (not that I really understand the difference in CGI or mod_rails or whatever, but they say Passenger is the simplest). So I'm to understand that if I build an app in Rails 3, it won't run at all on this host? But damn, I already have these accounts under my reseller account there, all running static html and/or PHP stuff, right? So what now? How do I get all of this under one simple (and affordable) roof? Forgive my ignorance, but I just don't get it. Managing a VPS is cool and all, but entails learning server admin stuff and security... And it's expensive. I get that a shared and/or reseller "server-based" (forgive the terminology) may be inadequate for large-scale apps that use a lot of bandwidth... But what about for those of us who are building real (but small and low bandwidth) apps (with Rails) and who want to deploy them simply, cheaply, using the same conceptual approach as PHP? Even after learning all of this Ruby and Rails stuff for months, I'm questioning whether it's worth it when it comes to deployment. I want to build a small app, upload it to my home directory on a shared server account, and just make it run. Why should that be so hard? Am I just choosing the wrong language/framework? Forgive my ignorance in the subject; these questions are not rhetorical; just trying to learn here. So: 1) I'd appreciate if someone could give me a good rundown of how to understand deployment in Rails vs. PHP. 2) I'd appreciate if someone could address my issue with running a hosting/web business around reseller hosting (Hostgator) while also being able to host Rails apps. Can it be done? And how can a company like Hostgator completely ignore what's current in Rails/Ruby? Thanks.

    Read the article

  • installing ubuntu 13.04 along side window 7 64 bit

    - by Shikhar Subedi
    I have a 64 bit computer with windows OS. Here are my specifications: core i3 processor 4 gb ram nvdia ge210 hard disk with 680 gb memory In my windows installation I have C: drive with 104 gb, D: drive with 246gb and E: drive with 246gb memory. My dvd rom is in f: drive. I want to install ubuntu 13.04 64 bit along side windows 7. So i burned the ubuntu 64 bit iso image onto a dvd and restarted the computer. but in the choice for installations, there is no option to select installing ubuntu along side windows. There is an option to install ubuntu inside windows instead. There are other options as well. What should I do to get the option to install ubuntu along side windows. I think the problem is with the number of drives in windows. Please tell me how should I make a partition in windows 7 to install ubuntu. Thanks a lot..

    Read the article

  • What is hiberfil.sys and How Do I Delete It?

    - by The Geek
    You’re no doubt reading this article because there’s a gigantic hiberfil.sys file sitting in the root of your drive, and you want to get rid of it to free up some space… but you can’t! Luckily, you actually can delete it, and today we’ll show you how. The more memory you have in your PC, the bigger the file will be. So What is hiberfil.sys Anyway? Windows has two power management modes that you can choose from: one is Sleep Mode, which keeps the PC running in a low power state so you can almost instantly get back to what you were working on. The other is Hibernate mode, which completely writes the memory out to the hard drive, and then powers the PC down entirely, so you can even take the battery out, put it back in, start back up, and be right back where you were. Hibernate mode uses the hiberfil.sys file to store the the current state (memory) of the PC, and since it’s managed by Windows, you can’t delete the file. So if you never use it, and want to disable Hibernate mode, keep reading. Personally I stick with Sleep Mode the vast majority of the time, but I do use Hibernate quite often. Disable Hibernate (and Delete hiberfil.sys) in Windows 7 or Vista You’ll need to open an administrator mode command prompt by right-clicking on the command prompt in the start menu, and then choosing Run as Administrator. Once you’re there, type in the following command: powercfg -h off You should immediately notice that the Hibernate option is gone from the Shut down menu. You’ll also notice that the file is magically gone! For more about dealing with Hibernate like setting how long it takes to head into Hibernate mode, you can check out our article on How to Manage Hibernate Mode in Windows 7. Disabling Hibernate Mode in Windows XP It’s a lot easier in Windows XP to get rid of Hibernate mode… in fact, we’ve already covered it before, but we’ll cover it again. Just head into Control Panel –> Power Options, and then find the Hibernate tab. Uncheck the box, reboot your PC, and then you can delete the hiberfil.sys file. Similar Articles Productive Geek Tips How to Delete a System File in Windows 7 or VistaDisable Delete Confirmation Dialog in Windows 7 or VistaClear IE7 Browsing History From the Command LineHide, Delete, or Destroy the Recycle Bin Icon in Windows 7 or VistaClear the Auto-Complete Email Address Cache in Outlook TouchFreeze Alternative in AutoHotkey The Icy Undertow Desktop Windows Home Server – Backup to LAN The Clear & Clean Desktop Use This Bookmarklet to Easily Get Albums Use AutoHotkey to Assign a Hotkey to a Specific Window Latest Software Reviews Tinyhacker Random Tips DVDFab 6 Revo Uninstaller Pro Registry Mechanic 9 for Windows PC Tools Internet Security Suite 2010 Whoa ! Use Printflush to Solve Printing Problems Icelandic Volcano Webcams Open Multiple Links At One Go NachoFoto Searches Images in Real-time Office 2010 Product Guides

    Read the article

  • System Requirement Checking

    - by gl3829
    I am working on a game and want to strengthen its requirement checking to ensure that it can run successfully. Therefore, I am looking for information on what is useful to check before starting the game. As a simple example, Why check for a specific amount of memory? Should I as a game developer ensure a minimum amount of memory? I feel this information is usually skipped in many books and resources but is critical to be able to deliver a game that will run on many machines. I would appreciate if you answered with what you check in the system, why you check it and if you have a good resource about it, please include. Just to be a bit more specific, I'm developing in Windows.

    Read the article

  • No access to Samba shares

    - by koanhead
    I have three shared folders in my local home directory- that is to say, on my Ubuntu desktop's /home/me/. All were set up using "Sharing Options" in Nautilus' right-click menu. The standard "Music" and "Videos" folders are configured identically: the "Guest Access" box is checked, but the "Allow others to create and delete" is not. The third folder, called "shared", is configured to not allow Guest access but to allow others to modify files. I have not altered /etc/samba/smb.conf by hand, I have only used Sharing Options to create and modify these so-called "shares". My roommates have two Windows 7 computers and one Ubuntu Netbook Remix netbook. I have the aforementioned desktop machine and laptop running 10.04. None of these machines can access any of the shares. Attempts to access the Guest shares result in the message \\machine\directory is not accessible. The network name could not be found. This is the error message generated by a VM running Windows 2000. The other Windows machines generate a similar error. The Ubuntu laptop gives the error Unable to mount location: Failed to mount Windows share. Hurrah, once again, for informative error messages. That really helps a lot. When attempting to browse the folder called "shared" from the laptop, I'm confronted with a password dialog. This behavior is the same will all machines I've tried in the situation. On entering my username and password for the account to which the shares belong, the password dialog briefly disappears and is replaced with an identical dialog. No error message, useful or not, appears. When attempting to browse this folder with the VM, the outcome is the same except that the password dialog helpfully states "incorrect username or password". My assumption is that the username and password in question is that of the user which owns the shares. I have tried all other username and password combinations available in this context and the outcome is the same. I would like to be able to share files. Sharing them with Windows machines is a nice feature, or would be if it was available. Really I consider sharing files between two machines with the same version of the same operating system kind of a minimum condition for network usability. Samba last functioned reliably for me more than ten years ago. I have attempted to use it on and off since then with only intermittent success. Oh, and "Personal File Sharing" from the Preferences menu does not result in an entry in Places → Network → my-server. In fact, the old entry "MY-SERVER" goes away and is replaced by "koanhead's public files on my-server", which when I attempt to open it from the laptop gives a "DBus.Error.NoReply: Message did not receive a reply." I know I come here and gripe about Ubuntu a lot, but on the other hand I spend literally hours every day trying to fix things in Ubuntu. It's a good system which aspires to greatness, which is why things like this either Need to work; or Be adequately documented. Ideally both would be the case. Anyway, rant over. Hopefully someone will have some insight on this issue. Thanks all who bother to read this wall o'text for your time.

    Read the article

  • Analyzing I/O Characteristics and Sizing Storage Systems for SQL Server Database Applications

    Understanding how to analyze the characteristics of I/O patterns in the Microsoft® SQL Server® data management software and how they relate to a physical storage configuration is useful in determining deployment requirements for any given workload. A well-performing I/O subsystem is a critical component of any SQL Server application. I/O subsystems should be sized in the same manner as other hardware components such as memory and CPU. As workloads increase it is common to increase the number of CPUs and increase the amount of memory. Increasing disk resources is often necessary to achieve the right performance, even if there is already enough capacity to hold the data. Too many SQL Servers to keep up with?Download a free trial of SQL Response to monitor your SQL Servers in just one intuitive interface."The monitoringin SQL Response is excellent." Mike Towery.

    Read the article

  • 100% APC Fragmentation - Cacherouter & Pressflow install

    - by granttoth
    My APC cache has a 100% fragmentation. I'm not quite sure I understand what is going on here. For testing I jacked the available memory up to 512. After a day the total available free memory shows 73% but I still have 100% fragmentation. Would you gurus please look at my settings and offer your advice? Oh, I have read people suggest that I disable apc.stat when possible but when I do the site crashes. I am using the Pressflow build of Drupal 6 with the cacherouter module installed. Edit: (added screenshot) http://i.imgur.com/DqZEX.png

    Read the article

  • How do I prevent Ubuntu gradually slowing down to a stop?

    - by user29165
    I really do not know what is causing the problem of my desktop environment (D.E.) gradually slowing down. It seems to happen in Gnome 3.2, LXDE, XFCE, and KDE. I am running Ubuntu 11.10 and this problem started happening from a fresh install. I have noticed that if I restart Gnome or otherwise re-log-in with any of the D.E.s the speed resets to normal. I don't seem to have and memory leaks that account for it and there are not any processes that are using excessive CPU cycles. Due to the symptoms I am guessing that there is an underlying package that interacts with all D.E.s that is the source of the problem. Just to clarify, in extreme situations, if I let the slowdown continue without a restart of the D.E. my system will finally get to a point where everything, even my clock, freezes. The time over which Gnome slows down (noticeably after 17 hrs) is much less than LXDE, or XFCE but eventually they freeze as well. I didn't mention Unity since I haven't used it enough to verify the problem, but I don't see why it should be different. Just in case this is relevant, I Suspend my computer rather than turn it off. I do this because of the greatly reduced load time and the 17 hrs I stated above is actual up-time, not time where the D.E. is actually active. However, the slow down does not seem to be affected by how long the computer has been in suspend mode. I know that it is possible that this problem is due to an interaction between two or more of the applications that I use and as such it may not be able to be duplicated by others. In the end I am just wondering (a) are other people experiencing this issue and (b) does anyone have some advice on where to start looking for a solution if one is not already known. I am even open to the idea of switching to the beta release of 12.04 if anyone thinks it will solve the problem. Edit: I took a video of my latest freeze that you can watch at http://youtu.be/flKUqUzCmdE, sorry about the audio. Edit: Since that video I checked my memory for errors and tried installing the proprietary video drivers. No memory errors were found and the proprietary video drivers made the display unusable so I had to uninstall them. Any thoughts?

    Read the article

  • Problems while installing Ubuntu 12.04 64 & 32 bits from LiveCd

    - by user76104
    I am trying to install Ubuntu on my new pc but I am encountering problems. When I boot from the installation CD, everything runs fine until the "window" when the user has to decide to Try Ubuntu or Install it in the machine. Well that "window" appears in blank, and my mouse and keyboard behaves really slow. I can't do anything , so i have to shut it down by pressing power button. The specification of my pc are this Motherboard: Gigabyte ex58 ud7 CPU: i7 950 HD: Western digital caviar black Int. memory: 6gb memory corsair Graphics: evga gtx580 I really need to install Ubuntu or another Linux distribution, i am using de seismic Unix program {Edit : Guess it is this} on my laptop. I hope someone can help me.

    Read the article

  • Resource Managers - Are they any good?

    - by The Communist Duck
    Hey. I've seen many a time in source code, things like this [well, this is more of a pseudo C++ idea of mine] type defshared_ptr ResourcePtr;// for ease ResourcePtr sound1 = resourceManager.Get("boom.ogg"); sound1-Play(); ResourcePtr sprite = resourceManager.Get("sprite.png"); I was just wondering how useful a class like this was, something that: Loaded media files Stored them in memory Did this at the start of a level - loading screen. Cleaned up Rather than having a system of: Resources are held by entities only, or loose. Responsible for own load into memory. The first is a 'manager' as such; something I feel indicates it's wrong to use. However, it allows for something like a vector of resource names to be passed, rather than having to scramble around finding everything that needs to be loaded.

    Read the article

  • SharePoint 2010 slow page response time suddenly !

    - by H(at)Ni
    Hello, One of my customers faced a problem that suddenly their SharePoint portal was loading extremely slower than usual. After some basic troubleshooting I did not find anything suspicious in the ULS logs, IIS logs or even Event logs. After that, I came to the part that I like most which is capturing a memory dump for the IIS process and analyzing the threads running. I searched for any common mistakes like looping a large list, calling a remote web service but couldn't find any. After a deep analysis of the memory dump (Which was done by an Escalation Engineer for SharePoint), it seems that the farm root certificate was missing and therefore was trying to validate it from the internet every time the user requests to load the page and this was the resolution http://support.microsoft.com/kb/2625048 Cheers,

    Read the article

  • Using UNION in a query with PHP [migrated]

    - by work
    I have an SQL query which links 3 tables using UNION: $sql ="(SELECT Drive.DriveID,Ram.Memory from Drive,Ram where Drive.DriveID = Ram.RamID) UNION (SELECT Drive.DriveID,External.Memory from Drive, External where Drive.DriveID = External.ExtID)"; Suppose I want to get Ram.Name as well. How do I do this? If I use Ram.Name in the first SELECT statement it would not produce the correct result. Any method for tackling this? I want to do it using UNION.

    Read the article

  • Debugging Silverlight crash

    - by RHLopez
    I am trying to debug an IE 8 crash caused by a Silverlight application. I managed to find some articles on how to do a memory dump when a process crashes. I loaded the dump in windbg and ran !analyze -v. Below is the result. I am stuck at what further steps I can take to figure out what module or library that is running in Silverlight is causing the crash. So all I have right now is the crash in IE is caused by an Access violation (attempt to execute non-executable address) and from what is in the stack trace that some animation is running in Silverlight. Any tips or articles that would help me debug this will be appreciated. This dump file has an exception of interest stored in it. The stored exception information can be accessed via .ecxr. (1864.1560): Access violation - code c0000005 (first/second chance not available) eax=00000000 ebx=00000000 ecx=1b11fc58 edx=5c6f007d esi=00000000 edi=193b8e08 eip=00000000 esp=0f61f750 ebp=0f61f76c iopl=0 nv up ei pl nz na pe nc cs=0023 ss=002b ds=002b es=002b fs=0053 gs=002b efl=00010206 00000000 ?? ??? FAULTING_IP: +56b3952f04ebde68 748bc9f1 654c dec esp EXCEPTION_RECORD: ffffffff -- (.exr 0xffffffffffffffff) ExceptionAddress: 748bc9f1 ExceptionCode: c0000005 (Access violation) ExceptionFlags: 00000000 NumberParameters: 2 Parameter[0]: 00000008 Parameter[1]: 00000000 Attempt to execute non-executable address 00000000 PROCESS_NAME: iexplore.exe ERROR_CODE: (NTSTATUS) 0xc0000005 - The instruction at 0x%08lx referenced memory at 0x%08lx. The memory could not be %s. EXCEPTION_CODE: (NTSTATUS) 0xc0000005 - The instruction at 0x%08lx referenced memory at 0x%08lx. The memory could not be %s. EXCEPTION_PARAMETER1: 00000008 EXCEPTION_PARAMETER2: 00000000 WRITE_ADDRESS: 00000000 FOLLOWUP_IP: agcore!CFrameworkElement::SetValue+1d7 5c704fa8 84c0 test al,al FAILED_INSTRUCTION_ADDRESS: +56b3952f04ebde68 748bc9f1 654c dec esp NTGLOBALFLAG: 0 APPLICATION_VERIFIER_FLAGS: 0 FAULTING_THREAD: 00001560 BUGCHECK_STR: APPLICATION_FAULT_SOFTWARE_NX_FAULT_NULL PRIMARY_PROBLEM_CLASS: SOFTWARE_NX_FAULT_NULL DEFAULT_BUCKET_ID: SOFTWARE_NX_FAULT_NULL LAST_CONTROL_TRANSFER: from 5c704fa8 to 00000000 STACK_TEXT: WARNING: Frame IP not in any known module. Following frames may be wrong. 0f61f74c 5c704fa8 1b17a134 193b8e08 0e690e14 0x0 0f61f76c 5c712360 0e690e14 1b17a134 0e690e14 agcore!CFrameworkElement::SetValue+0x1d7 0f61f788 5c7123a8 0e690e14 1b17a134 0e690e14 agcore!CShape::SetValue+0x72 0f61f7a0 5c70a6ff 0e690e14 1b17a134 00000000 agcore!CEllipse::SetValue+0x3b 0f61f7d0 5c752c2b 1b17a090 193b8e08 00000000 agcore!CAnimation::DoSetValue+0x50 0f61f810 5c7a7fb1 0f61f884 0f61f868 1b17a090 agcore!CAnimation::UpdateAnimationUsingKeyFrames+0x3b5 0f61f82c 5c707146 00000000 00000000 00000000 agcore!CAnimation::UpdateAnimation+0x184 0f61f87c 5c7071e5 3e4c8000 0f61f8cc 00000000 agcore!CTimeline::ComputeState+0x13a 0f61f89c 5c706d49 193f82b0 0f61f8cc 0f61f8d4 agcore!CTimelineGroup::ComputeState+0x8c 0f61f8ac 5c7069c7 3e4c8000 0f61f8cc 0b111f60 agcore!CStoryboard::ComputeState+0x48 0f61f8d4 5c706a29 0e6a0ca0 00000000 0e490070 agcore!CTimeManager::Tick+0x79 0f61f8e8 5c78f960 0b0e6d68 0f61f990 00000000 agcore!CCoreServices::Tick+0x21 0f61f940 5c706ac2 0b111f60 0e42ca08 ffffffff agcore!CCoreServices::Draw+0x140 0f61f964 67ac141c 0af99b90 00000000 0f61f990 agcore!CCoreServices::Draw+0x2d 0f61f9b4 67a933c2 0f61f9c8 00000000 00000000 npctrl!CXcpBrowserHost::OnTick+0x1b1 0f61f9e0 67a927c6 0064069c 00000402 00000000 npctrl!CXcpDispatcher::Tick+0xf3 0f61fa08 67a92709 0064069c 00000402 00000000 npctrl!CXcpDispatcher::OnReentrancyProtectedWindowMessage+0xcd 0f61fa28 764b6238 0064069c 00000402 00000000 npctrl!CXcpDispatcher::WindowProc+0xb8 0f61fa54 764b68ea 67a9269d 0064069c 00000402 user32!InternalCallWinProc+0x23 0f61facc 764b7d31 00000000 67a9269d 0064069c user32!UserCallWinProcCheckWow+0x109 0f61fb2c 764b7dfa 67a9269d 00000000 0f61fbb4 user32!DispatchMessageWorker+0x3bc 0f61fb3c 6fe504a6 0f61fb54 00000000 0ab11908 user32!DispatchMessageW+0xf 0f61fbb4 6fe60446 0af956a0 00000000 0b18a338 ieframe!CTabWindow::_TabWindowThreadProc+0x452 0f61fc6c 769d49bd 0ab11908 00000000 0f61fc88 ieframe!LCIETab_ThreadProc+0x2c1 0f61fc7c 76e53677 0b18a338 0f61fcc8 77829d72 iertutil!CIsoScope::RegisterThread+0xab 0f61fc88 77829d72 0b18a338 7dbc895d 00000000 kernel32!BaseThreadInitThunk+0xe 0f61fcc8 77829d45 769d49af 0b18a338 00000000 ntdll!__RtlUserThreadStart+0x70 0f61fce0 00000000 769d49af 0b18a338 00000000 ntdll!_RtlUserThreadStart+0x1b SYMBOL_STACK_INDEX: 1 SYMBOL_NAME: agcore!CFrameworkElement::SetValue+1d7 FOLLOWUP_NAME: MachineOwner MODULE_NAME: agcore IMAGE_NAME: agcore.dll DEBUG_FLR_IMAGE_TIMESTAMP: 4a67e422 STACK_COMMAND: ~44s; .ecxr ; kb FAILURE_BUCKET_ID: SOFTWARE_NX_FAULT_NULL_c0000005_agcore.dll!CFrameworkElement::SetValue BUCKET_ID: APPLICATION_FAULT_SOFTWARE_NX_FAULT_NULL_BAD_IP_agcore!CFrameworkElement::SetValue+1d7

    Read the article

  • Is it possible to implement bitwise operators using integer arithmetic?

    - by Statement
    Hello World! I am facing a rather peculiar problem. I am working on a compiler for an architecture that doesn't support bitwise operations. However, it handles signed 16 bit integer arithmetics and I was wondering if it would be possible to implement bitwise operations using only: Addition (c = a + b) Subtraction (c = a - b) Division (c = a / b) Multiplication (c = a * b) Modulus (c = a % b) Minimum (c = min(a, b)) Maximum (c = max(a, b)) Comparisons (c = (a < b), c = (a == b), c = (a <= b), et.c.) Jumps (goto, for, et.c.) The bitwise operations I want to be able to support are: Or (c = a | b) And (c = a & b) Xor (c = a ^ b) Left Shift (c = a << b) Right Shift (c = a b) (All integers are signed so this is a problem) Signed Shift (c = a b) One's Complement (a = ~b) (Already found a solution, see below) Normally the problem is the other way around; how to achieve arithmetic optimizations using bitwise hacks. However not in this case. Writable memory is very scarce on this architecture, hence the need for bitwise operations. The bitwise functions themselves should not use a lot of temporary variables. However, constant read-only data & instruction memory is abundant. A side note here also is that jumps and branches are not expensive and all data is readily cached. Jumps cost half the cycles as arithmetic (including load/store) instructions do. On other words, all of the above supported functions cost twice the cycles of a single jump. Some thoughts that might help: I figured out that you can do one's complement (negate bits) with the following code: // Bitwise one's complement b = ~a; // Arithmetic one's complement b = -1 - a; I also remember the old shift hack when dividing with a power of two so the bitwise shift can be expressed as: // Bitwise left shift b = a << 4; // Arithmetic left shift b = a * 16; // 2^4 = 16 // Signed right shift b = a >>> 4; // Arithmetic right shift b = a / 16; For the rest of the bitwise operations I am slightly clueless. I wish the architects of this architecture would have supplied bit-operations. I would also like to know if there is a fast/easy way of computing the power of two (for shift operations) without using a memory data table. A naive solution would be to jump into a field of multiplications: b = 1; switch (a) { case 15: b = b * 2; case 14: b = b * 2; // ... exploting fallthrough (instruction memory is magnitudes larger) case 2: b = b * 2; case 1: b = b * 2; } Or a Set & Jump approach: switch (a) { case 15: b = 32768; break; case 14: b = 16384; break; // ... exploiting the fact that a jump is faster than one additional mul // at the cost of doubling the instruction memory footprint. case 2: b = 4; break; case 1: b = 2; break; }

    Read the article

  • Javascript Closures - What are the negatives?

    - by vol7ron
    Question: There seem to be many benefits to Closures, but what are the negatives (memory leakage? obfuscation problems? bandwidth increasage?)? Additionally, is my understanding of Closures correct? Finally, once closures are created, can they be destroyed? I've been reading a little bit about Javascript Closures. I hope someone a little more knowledgeable will guide my assertions, correcting me where wrong. Benefits of Closures: Encapsulate the variables to a local scope, by using an internal function. The anonymity of the function is insignificant. What I've found helpful is to do some basic testing, regarding local/global scope: <script type="text/javascript"> var global_text = ""; var global_count = 0; var global_num1 = 10; var global_num2 = 20; var global_num3 = 30; function outerFunc() { var local_count = local_count || 0; alert("global_num1: " + global_num1); // global_num1: undefined var global_num1 = global_num1 || 0; alert("global_num1: " + global_num1); // global_num1: 0 alert("global_num2: " + global_num2); // global_num2: 20 global_num2 = global_num2 || 0; // (notice) no definition with 'var' alert("global_num2: " + global_num2); // global_num2: 20 global_num2 = 0; alert("local_count: " + local_count); // local_count: 0 function output() { global_num3++; alert("local_count: " + local_count + "\n" + "global_count: " + global_count + "\n" + "global_text: " + global_text ); local_count++; } local_count++; global_count++; return output; } var myFunc = outerFunc(); myFunc(); /* Outputs: ********************** * local_count: 1 * global_count: 1 * global_text: **********************/ global_text = "global"; myFunc(); /* Outputs: ********************** * local_count: 2 * global_count: 1 * global_text: global **********************/ var local_count = 100; myFunc(); /* Outputs: ********************** * local_count: 3 * global_count: 1 * global_text: global **********************/ alert("global_num1: " + global_num1); // global_num1: 10 alert("global_num2: " + global_num2); // global_num2: 0 alert("global_num3: " + global_num3); // global_num3: 33 </script> Interesting things I took out of it: The alerts in outerFunc are only called once, which is when the outerFunc call is assigned to myFunc (myFunc = outerFunc()). This assignment seems to keep the outerFunc open, in what I would like to call a persistent state. Everytime myFunc is called, the return is executed. In this case, the return is the internal function. Something really interesting is the localization that occurs when defining local variables. Notice the difference in the first alert between global_num1 and global_num2, even before the variable is trying to be created, global_num1 is considered undefined because the 'var' was used to signify a local variable to that function. -- This has been talked about before, in the order of operation for the Javascript engine, it's just nice to see this put to work. Globals can still be used, but local variables will override them. Notice before the third myFunc call, a global variable called local_count is created, but it as no effect on the internal function, which has a variable that goes by the same name. Conversely, each function call has the ability to modify global variables, as noticed by global_var3. Post Thoughts: Even though the code is straightforward, it is cluttered by alerts for you guys, so you can plug and play. I know there are other examples of closures, many of which use anonymous functions in combination with looping structures, but I think this is good for a 101-starter course to see the effects. The one thing I'm concerned with is the negative impact closures will have on memory. Because it keeps the function environment open, it is also keeping those variables stored in memory, which may/may not have performance implications, especially regarding DOM traversals and garbage collection. I'm also not sure what kind of role this will play in terms of memory leakage and I'm not sure if the closure can be removed from memory by a simple "delete myFunc;." Hope this helps someone, vol7ron

    Read the article

  • Random Complete System Unresponsiveness Running Mathematical Functions

    - by Computer Guru
    I have a program that loads a file (anywhere from 10MB to 5GB) a chunk at a time (ReadFile), and for each chunk performs a set of mathematical operations (basically calculates the hash). After calculating the hash, it stores info about the chunk in an STL map (basically <chunkID, hash>) and then writes the chunk itself to another file (WriteFile). That's all it does. This program will cause certain PCs to choke and die. The mouse begins to stutter, the task manager takes 2 min to show, ctrl+alt+del is unresponsive, running programs are slow.... the works. I've done literally everything I can think of to optimize the program, and have triple-checked all objects. What I've done: Tried different (less intensive) hashing algorithms. Switched all allocations to nedmalloc instead of the default new operator Switched from stl::map to unordered_set, found the performance to still be abysmal, so I switched again to Google's dense_hash_map. Converted all objects to store pointers to objects instead of the objects themselves. Caching all Read and Write operations. Instead of reading a 16k chunk of the file and performing the math on it, I read 4MB into a buffer and read 16k chunks from there instead. Same for all write operations - they are coalesced into 4MB blocks before being written to disk. Run extensive profiling with Visual Studio 2010, AMD Code Analyst, and perfmon. Set the thread priority to THREAD_MODE_BACKGROUND_BEGIN Set the thread priority to THREAD_PRIORITY_IDLE Added a Sleep(100) call after every loop. Even after all this, the application still results in a system-wide hang on certain machines under certain circumstances. Perfmon and Process Explorer show minimal CPU usage (with the sleep), no constant reads/writes from disk, few hard pagefaults (and only ~30k pagefaults in the lifetime of the application on a 5GB input file), little virtual memory (never more than 150MB), no leaked handles, no memory leaks. The machines I've tested it on run Windows XP - Windows 7, x86 and x64 versions included. None have less than 2GB RAM, though the problem is always exacerbated under lower memory conditions. I'm at a loss as to what to do next. I don't know what's causing it - I'm torn between CPU or Memory as the culprit. CPU because without the sleep and under different thread priorities the system performances changes noticeably. Memory because there's a huge difference in how often the issue occurs when using unordered_set vs Google's dense_hash_map. What's really weird? Obviously, the NT kernel design is supposed to prevent this sort of behavior from ever occurring (a user-mode application driving the system to this sort of extreme poor performance!?)..... but when I compile the code and run it on OS X or Linux (it's fairly standard C++ throughout) it performs excellently even on poor machines with little RAM and weaker CPUs. What am I supposed to do next? How do I know what the hell it is that Windows is doing behind the scenes that's killing system performance, when all the indicators are that the application itself isn't doing anything extreme? Any advice would be most welcome.

    Read the article

  • perl threading problem

    - by Alice Wozownik
    I'm writing a multithreaded website uptime checker in perl, and here is the basic code so far (includes only threading part): !/usr/bin/perl use LWP::UserAgent; use Getopt::Std; use threads; use threads::shared; my $maxthreads :shared = 50; my $threads :shared = 0; print "Website Uptime Checker\n"; my $infilename = $ARGV[0]; chomp($infilename); open(INFILE, $infilename); my $outfilename = $ARGV[1]; chomp($outfilename); open(OUTFILE, "" . $outfilename); OUTFILE-autoflush(1); while ($site = ) { chomp($site); while (1) { if ($threads < $maxthreads) { $threads++; my $thr = threads-create(\&check_site, $site); $thr-detach(); last; } else { sleep(1); } } } while ($threads 0) { sleep(1); } sub check_site { $server = $_[0]; print "$server\n"; $threads--; } It gives an error after a while: Can't call method "detach" on an undefined value at C:\perl\webchecker.pl line 28, line 245. What causes this error? I know it is at detach, but what am I doing wrong in my code? Windows shows lots of free memory, so it should not be the computer running out of memory, this error occurs even if I set $maxthreads as low as 10 or possibly even lower.

    Read the article

  • Will IOC solve our problems?

    - by user127954
    Just trying to implement unit testing into a brownfield type system. Be aware i'm relatively new into the unit testing world. Its going to be a gradual migration of course because there are just so many areas of pain. The current problem i'm trying to solve is we followed a lot of bad practices from our VB6 days and in the conversion of our app to .Net. We have LOT AN LOTS of shared/static functions which call other shared functions and those call others and so on. Sometimes depedencies are passed in as parameters and sometimes they are just newed up within the calling function. I've already instructed our developers to stop creating shared functions and instead create instance members and only use those instance members off of interfaces but that doesn't alleviate the current situation. So you must recursively pass in each and every dependency at the top layer for each function in your code path and method signatures are turning into a mess. I'm hoping this is something that IOC will fix. Currently we are using NUnit/Moq and i'm starting to investigate StructureMap. So far i understand that you pretty much tell StructureMap for x interface i want to default to the concrete class y: ObjectFactory.Initialize(x=>{x.ForRequestType<IInterface>().TheDefaultIsConcreteType<MyClass>()}); Then to runtime: var mytype = ObjectFactory.GetInstance<IInterface>(); the IOC container will initialize the correct type for you. Not sure yet how to swap a fake in for the concrete type but hopefully thats simple. Again will IOC solve the problems i was talking about above? Is there a specific IOC framework that will do it better than StructureMap or can they all handle this situation. Any help would be much appreciated.

    Read the article

  • Facebook like and share create a fanpage

    - by nblumoe
    We are using the facebook like plugin with the share button. The URL points to a resource of our app. For example http://apps.facebook.com/appname/resources/id The first time this resource/url is shared or liked, everything works fine. The share for example holds the URL given above. But if the same resource/url is shared again, an error occurs. Facebook did create a fanpage for that resource like http://www.facebook.com/pages/appname So from now on, share/likes refer to that page instead of the resource/url of our app. The URL we use for the like plugin is correct and always points to the app resource URL. The fbappid in there is correct, too. Furthermore the page of the resource holds open graph meta tags like og:url, also pointing to the correct URL. The facebook linter/debugger returns URLs to the correct app resource URLs, when checking the liked/shared resource. Why is a fanpage created instead and the URL exchanged in shares/likes? How to fix it? We want the share to include the URL of the app resource and to increase the like count for that open graph object.

    Read the article

  • Development environment for ASP.NET with EpiServer

    - by Binary255
    At our company we are going to develop more for the Windows platform than we have done up until now. As this scale of Windows development is new to us it would be nice with some feedback from experienced developers. Requirements we have: 5 developers from the beginning. 15 developers a year from now. All developers should be able to develop at the same time. Be able to develop solution for ASP.NET and EpiServer 5. Our idea: A shared server which developers use for development through Terminal Services. SQL Server Express. Start with some free express edition of Visual Studio, upgrade to a commercial version if we need the additional features. Use IIS and not the web server built into Visual Studio. Questions: Are we on the right track? In terms of license costs the above should be cheapest, right? What do you think about multiple developers doing development using a shared TS-server? Do you know of any company which has a similar development environment? Are we going to miss some features of the full Visual Studio version immediately? Is using Express version a bad choice? Is IIS the best choice? If use IIS the developers may use the same port for deployment. If we use the built in web server each one has to set their own port as we're sharing a machine. Comment answer: We are thinking about a shared server as it will most likely decrease the license costs. So it's purely a cost issue. We are using CVS for version control. Our situation is that we develop on Mac and Linux, that's why buying 1 server license + Visual Studio licenses seems to be a cost effective way of starting this type of development.

    Read the article

  • Groovlet + Tomcat: "unable to resolve class" when importing libraries

    - by Rob Hruska
    I'm having some trouble running a groovy servlet (groovlet) in tomcat that imports a library class. When I don't import anything the groovlet works correctly, but if I do import something that I expect to be on the classpath (I can import the same class successfully in a regular servlet), I see the following error: groovy.util.ScriptException: Could not parse scriptName: /MyGroovlet.groovy java.lang.RuntimeException: groovy.util.ScriptException: Could not parse scriptName: /MyGroovlet.groovy at groovy.servlet.GroovyServlet$1.call(GroovyServlet.java:123) ... Caused by: org.codehaus.groovy.control.MultipleCompilationErrorsException: startup failed, /MyGroovlet.groovy: 1: unable to resolve class com.mycompany.mypackage.MyLibraryClass @ line 1, column 1. The jar containing MyLibraryClass is in shared/lib, which is loaded by tomcat by the following in catalina.properties: shared.loader=...,${catalina.base}/shared/lib/*.jar,... My groovlets are mapped as described in the user guide in my application's web.xml: <servlet> <servlet-name>GroovyServlet</servlet-name> <servlet-class>groovy.servlet.GroovyServlet</servlet-class> </servlet> <servlet-mapping> <servlet-name>GroovyServlet</servlet-name> <url-pattern>*.groovy</url-pattern> </servlet-mapping> And here's the code for the groovlet, MyGroovlet.groovy: import com.mycompany.mypackage.MyLibraryClass MyLibraryClass.someStaticMethod() My groovlet is deployed to WEB-INF/groovy/MyGroovlet.groovy, per the GroovyServlet API. When I visit http://localhost:8080/myapplication/MyGroovlet.groovy, the error described previously is written to my application logs. Is there some way that I need to explicitly declare the runtime classpath for GroovyServlet? I've tried moving the library jar to several places, including WEB-INF/lib and moving the actual MyLibraryClass.class file to WEB-INF/classes, but with no luck.

    Read the article

< Previous Page | 248 249 250 251 252 253 254 255 256 257 258 259  | Next Page >