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  • sql jdbc getgeneratedkeys with mysql returns column "id" not found

    - by iamrohitbanga
    I want to retrieve the most recently updated value in the table using an insert query. these are the datatypes in my sql table. int(11) // primary key auto increment, not being assigned by sqlQuery varchar(30) timestamp // has a default value. but i am explicit assigning it using CURRENT_TIMESTAMP varchar(300) varchar(300) varchar(300) int(11) varchar(300) // java code statement.executeUpdate(sqlQuery, Statement.RETURN_GENERATED_KEYS); ResultSet rs = statement.getGeneratedKeys(); System.out.println("here: " + rs.getMetaData().getColumnCount()); System.out.println("here1: " + rs.getMetaData().getColumnName(1)); // none of the following 3 works System.out.println("id: " + rs.getInt(1)); System.out.println("id: " + rs.getInt("GENERATED_KEY")); System.out.println("id: " + rs.getInt("id")); for a bit of background see this

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  • Java static method parameters

    - by Blitzkr1eg
    Why does the following code return 100 100 1 1 1 and not 100 1 1 1 1 ? public class Hotel { private int roomNr; public Hotel(int roomNr) { this.roomNr = roomNr; } public int getRoomNr() { return this.roomNr; } static Hotel doStuff(Hotel hotel) { hotel = new Hotel(1); return hotel; } public static void main(String args[]) { Hotel h1 = new Hotel(100); System.out.print(h1.getRoomNr() + " "); Hotel h2 = doStuff(h1); System.out.print(h1.getRoomNr() + " "); System.out.print(h2.getRoomNr() + " "); h1 = doStuff(h2); System.out.print(h1.getRoomNr() + " "); System.out.print(h2.getRoomNr() + " "); } } Why does it appear to pass Hotel by-value to doStuff() ?

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  • This .NET code snippet will NOT actually create a cookie, right?

    - by Ryan
    I just realized that this cookie is not showing up like it should, and I checked the code which was not written by me but I am pretty sure that this is NOT enough to create a cookie right?? public static void CreateSSOCookies(string tokenID) { System.Web.HttpContext.Current.Response.Cookies["ssocookies"].Domain = System.Web.HttpContext.Current.Request.ServerVariables["SERVER_NAME"].ToString().ToLower(); System.Web.HttpContext.Current.Response.Cookies["ssocookies"].Value = tokenID.ToString(); System.Web.HttpContext.Current.Response.Cookies["ssocookies"].Path = "~/"; System.Web.HttpContext.Current.Response.Cookies["ssocookies"].Expires = DateTime.Now.AddDays(7); } If it does work, where is the cookie then? Is the cookie name 'ssocookies' ?

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  • How to return Json from WCF Service?

    - by Zinoo
    Hi, I have the piece of code below of a template Ajax enabled WCF service. What can i do to make it return JSon instead of XML? thanks. using System; using System.Linq; using System.Runtime.Serialization; using System.ServiceModel; using System.ServiceModel.Activation; [ServiceContract(Namespace = "WCFServiceEight")] [AspNetCompatibilityRequirements(RequirementsMode = AspNetCompatibilityRequirementsMode.Allowed)] public class CostService { // Add [WebGet] attribute to use HTTP GET [OperationContract] [WebGet] public double CostOfSandwiches(int quantity) { return 1.25 * quantity; } }

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  • Error when accessing IIS 7 server variable from ASP.Net MVC

    - by StephSpr
    I have an ASP.Net MVC application which works fine on IIS 6.0 / Windows Server 2003. When installed on IIS 7.5 / Windows Server 2008 (integrated mode), it works but when the application attempts to generate an URL, it runs into the following error: [NullReferenceException: Object reference not set to an instance of an object.] System.Web.HttpServerVarsCollection.Get(String name) +10960764 System.Web.Mvc.PathHelpers.GenerateClientUrlInternal(HttpContextBase httpContext, String contentPath) +345 System.Web.Mvc.PathHelpers.GenerateClientUrl(HttpContextBase httpContext, String contentPath) +80 System.Web.Mvc.UrlHelper.GenerateUrl(String routeName, String actionName, String controllerName, RouteValueDictionary routeValues, RouteCollection routeCollection, RequestContext requestContext, Boolean includeImplicitMvcValues) +256 System.Web.Mvc.UrlHelper.Action(String actionName, String controllerName, RouteValueDictionary routeValues) +36 It looks like IIS7 fails to return the server name. There should be a configuration to set, but I couldn't find anything like that. Do you have any idea to fix this issue ? Thanks,

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  • Converting Byte[] to String - Interbase to C# - InvalidCastException

    - by NorthernOutpost
    I'm using OleDbDataReader rdr to read a "Comments" field in BLOB form (sub_type 1 segment size 80) into a string from an Interbase DB, and I keep getting exceptions. Any suggestions? Attempt #1 ls_Chap_Comments.Add((rdr["Comments"]).ToString()); InvalidCastException: The data value could not be converted for reasons other than sign mismatch or data overflow. For example, the data was corrupted in the data store but the row was still retrievable." Attempt #2 byte[] b = new byte[100]; b = (byte[])rdr["Comments"]; string s = System.Text.ASCIIEncoding.ASCII.GetString(b); InvalidCastException: Unable to cast object of type System.String to type System.Byte[] Attempt #3 // 17 is the BLOB column zero-based location for "Comments" retval = rdr.GetBytes(17, startIndex, outbyte, 0, bufferSize); InvalidCastException: Unable to cast object of type System.String to type System.Byte[]. Any suggestions would be really appreciated!

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  • Change English numbers to Persian and vice versa in MVC (httpmodule)?

    - by Mohammad
    I wanna change all English numbers to Persian for showing to users. and change them to English numbers again for giving all requests (Postbacks) e.g: we have something like this in view IRQ170, I wanna show IRQ??? to users and give IRQ170 from users. I know, I have to use Httpmodule, But I don't know how ? Could you please guide me? Edit : Let me describe more : I've written the following http module : using System; using System.Collections.Specialized; using System.Diagnostics; using System.IO; using System.Text; using System.Text.RegularExpressions; using System.Web; using System.Web.UI; using Smartiz.Common; namespace Smartiz.UI.Classes { public class PersianNumberModule : IHttpModule { private StreamWatcher _watcher; #region Implementation of IHttpModule /// <summary> /// Initializes a module and prepares it to handle requests. /// </summary> /// <param name="context">An <see cref="T:System.Web.HttpApplication"/> that provides access to the methods, properties, and events common to all application objects within an ASP.NET application </param> public void Init(HttpApplication context) { context.BeginRequest += ContextBeginRequest; context.EndRequest += ContextEndRequest; } /// <summary> /// Disposes of the resources (other than memory) used by the module that implements <see cref="T:System.Web.IHttpModule"/>. /// </summary> public void Dispose() { } #endregion private void ContextBeginRequest(object sender, EventArgs e) { HttpApplication context = sender as HttpApplication; if (context == null) return; _watcher = new StreamWatcher(context.Response.Filter); context.Response.Filter = _watcher; } private void ContextEndRequest(object sender, EventArgs e) { HttpApplication context = sender as HttpApplication; if (context == null) return; _watcher = new StreamWatcher(context.Response.Filter); context.Response.Filter = _watcher; } } public class StreamWatcher : Stream { private readonly Stream _stream; private readonly MemoryStream _memoryStream = new MemoryStream(); public StreamWatcher(Stream stream) { _stream = stream; } public override void Flush() { _stream.Flush(); } public override int Read(byte[] buffer, int offset, int count) { int bytesRead = _stream.Read(buffer, offset, count); string orgContent = Encoding.UTF8.GetString(buffer, offset, bytesRead); string newContent = orgContent.ToEnglishNumber(); int newByteCountLength = Encoding.UTF8.GetByteCount(newContent); Encoding.UTF8.GetBytes(newContent, 0, Encoding.UTF8.GetByteCount(newContent), buffer, 0); return newByteCountLength; } public override void Write(byte[] buffer, int offset, int count) { string strBuffer = Encoding.UTF8.GetString(buffer, offset, count); MatchCollection htmlAttributes = Regex.Matches(strBuffer, @"(\S+)=[""']?((?:.(?![""']?\s+(?:\S+)=|[>""']))+.)[""']?", RegexOptions.IgnoreCase | RegexOptions.Multiline); foreach (Match match in htmlAttributes) { strBuffer = strBuffer.Replace(match.Value, match.Value.ToEnglishNumber()); } MatchCollection scripts = Regex.Matches(strBuffer, "<script[^>]*>(.*?)</script>", RegexOptions.Singleline | RegexOptions.IgnoreCase | RegexOptions.Multiline | RegexOptions.IgnorePatternWhitespace); foreach (Match match in scripts) { MatchCollection values = Regex.Matches(match.Value, @"([""'])(?:(?=(\\?))\2.)*?\1", RegexOptions.Singleline | RegexOptions.IgnoreCase | RegexOptions.Multiline | RegexOptions.IgnorePatternWhitespace); foreach (Match stringValue in values) { strBuffer = strBuffer.Replace(stringValue.Value, stringValue.Value.ToEnglishNumber()); } } MatchCollection styles = Regex.Matches(strBuffer, "<style[^>]*>(.*?)</style>", RegexOptions.Singleline | RegexOptions.IgnoreCase | RegexOptions.Multiline | RegexOptions.IgnorePatternWhitespace); foreach (Match match in styles) { strBuffer = strBuffer.Replace(match.Value, match.Value.ToEnglishNumber()); } byte[] data = Encoding.UTF8.GetBytes(strBuffer); _memoryStream.Write(data, offset, count); _stream.Write(data, offset, count); } public override string ToString() { return Encoding.UTF8.GetString(_memoryStream.ToArray()); } #region Rest of the overrides public override bool CanRead { get { throw new NotImplementedException(); } } public override bool CanSeek { get { throw new NotImplementedException(); } } public override bool CanWrite { get { throw new NotImplementedException(); } } public override long Seek(long offset, SeekOrigin origin) { throw new NotImplementedException(); } public override void SetLength(long value) { throw new NotImplementedException(); } public override long Length { get { throw new NotImplementedException(); } } public override long Position { get { throw new NotImplementedException(); } set { throw new NotImplementedException(); } } #endregion } } It works well, but It converts all numbers in css and scripts files to Persian and it causes error.

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  • Array::ConvertAll in managed C++

    - by danny.lesnik
    This is a continuation from this post. I'm trying to parse this string in managed C++: String ^ rgba = "[0.09019608,0.5176471,0.9058824,1]"; cli::array<System::Double> ^ RGB = System::Array::ConvertAll<String,cli::array<System::Double> >((rgba->Substring(1,rgba->Length-2)->Split(',')),double::Parse); Compiler throws me the following error: Error 15 error C2770: invalid explicit generic argument(s) for 'cli::array<Type,dimension> ^System::Array::ConvertAll(cli::array<TInput,1> ^,System::Converter<TInput,TOutput> ^)' What am I doing wrong?

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  • C# - opening process and changig window position

    - by bartq
    I want to open from c# an application (standalone flashplayer) and set it position to (0,0) on the screen. How can I do this? So far I've managed to open flashplayer: using System; using System.Collections.Generic; using System.Linq; using System.Text; using System.Diagnostics; namespace swflauncher { class Program { static void Main(string[] args) { Process flash = new Process(); flash.StartInfo.WindowStyle = ProcessWindowStyle.Normal; flash.StartInfo.FileName = "D:\\development\\flex4\\runtimes\\player\\10\\win\\FlashPlayer.exe"; flash.Start(); } } }

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  • How to anti-alias the fonts in visual studio in windows forms application?

    - by user1781077
    i want my font to be anti aliased like this so that it looks more professionalenter link description heredoes any one know the code to anti alias the fonts so that the project looks more professional.tell me the code and where to insert it in the project.As of now the fonts looks jaggy the programming language is visual C# 4.0 .net and IDE is VS 2010 for example this is a label1 what do I need to insert to anti alias this.label1.AutoSize = true; this.label1.Font = new System.Drawing.Font("Segoe UI", 8.25F, System.Drawing.FontStyle.Regular, System.Drawing.GraphicsUnit.Point, ((byte)(0))); this.label1.Location = new System.Drawing.Point(189, 187); this.label1.Name = "label1"; this.label1.Size = new System.Drawing.Size(31, 13); this.label1.TabIndex = 0; this.label1.Text = "from";

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  • Collections in C#

    - by Oghenero
    am converting a vb.net component to c#, i get this error Using the generic type 'System.Collections.ObjectModel.Collection<T>' requires '1' type arguments This is what i did in VB.NET i had this Private _bufferCol As Collection i did this in c# private Collection _bufferCol = new Collection(); My declaration is using Microsoft.VisualBasi; using System.Collections; using System.Collections.Generic; using System.ComponentModel; using System.Collections.ObjectModel; Can any body help me please.

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  • When should ThreadLocal be used instead of Thread.SetData/Thread.GetData?

    - by Jon Ediger
    Prior to .net 4.0, I implemented a solution using named data slots in System.Threading.Thread. Now, in .net 4.0, there is the idea of ThreadLocal. How does ThreadLocal usage compare to named data slots? Does the ThreadLocal value get inherited by children threads? Is the idea that ThreadLocal is a simplified version of using named data slots? An example of some stuff using named data slots follows. Could this be simplified through use of ThreadLocal, and would it retain the same properties as the named data slots? public static void SetSliceName(string slice) { System.Threading.Thread.SetData(System.Threading.Thread.GetNamedDataSlot(SliceVariable), slice); } public static string GetSliceName(bool errorIfNotFound) { var slice = System.Threading.Thread.GetData(System.Threading.Thread.GetNamedDataSlot(SliceVariable)) as string; if (errorIfNotFound && string.IsNullOrEmpty(slice)) {throw new ConfigurationErrorsException("Server slice name not configured.");} return slice; }

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  • strange bug - how to pause a java program?

    - by TerraNova993
    I'm trying to: display a text in a jLabel, wait for two seconds, then write a new text in the jLabel this should be simple, but I get a strange bug: the first text is never written, the application just waits for 2 seconds and then displays the final text. here is the example code: private void testButtonActionPerformed(java.awt.event.ActionEvent evt) { displayLabel.setText("Clicked!"); // first method with System timer /* long t0= System.currentTimeMillis(); long t1= System.currentTimeMillis(); do{ t1 = System.currentTimeMillis(); } while ((t1 - t0) < (2000)); */ // second method with thread.sleep() try { Thread.currentThread().sleep(2000); } catch (InterruptedException e) {} displayLabel.setText("STOP"); } with this code, the text "Clicked!" is never displayed. I just get a 2 seconds - pause and then the "STOP" text. I tried to use System timer with a loop, or Thread.sleep(), but both methods give the same result.

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  • C# Console Application Output to .csv file

    - by Zinn
    I am trying to make a program that will show the numbers: 1, 10 +30 2, 40 (the scale goes up in this pattern by adding 20 to the last number added) 3, 90 +50 4, 160 5, 250 +70 So far I have this code: using System; using System.Collections.Generic; using System.Linq; using System.Text; using System.IO;// namespace Myloop { class Program { static void Main(string[] args) /// </summary> { StreamWriter myOutputStream = new StreamWriter("loopdata.csv"); int forloop; for (forloop = 1; forloop < 21; forloop++) Console.WriteLine(forloop); Console.ReadLine(); myOutputStream.Close(); } } } This is showing the first sequence of numbers 1 - 20, but could anyone give me any guidance how to do the other sequence next to it in the console application and how I can output these to a .csv file, as the information I have so far doesn't appear in the .csv file

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  • C# - opening process and changing window position

    - by bartq
    I want to open from c# an application (standalone flashplayer) and set it position to (0,0) on the screen. How can I do this? So far I've managed to open flashplayer: using System; using System.Collections.Generic; using System.Linq; using System.Text; using System.Diagnostics; namespace swflauncher { class Program { static void Main(string[] args) { Process flash = new Process(); flash.StartInfo.WindowStyle = ProcessWindowStyle.Normal; flash.StartInfo.FileName = "D:\\development\\flex4\\runtimes\\player\\10\\win\\FlashPlayer.exe"; flash.Start(); } } }

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  • ASP.NET UserControl Uri property

    - by Roedel
    I want to pass a property of the type System.Uri to an WebControl from inside an aspx page. Is it possible to pass the property like that: <MyUserControl id="myusercontrol" runat="server"> <MyUrlProperty> <System.Uri>http://myurl.com/</System.Uri> </MyUrlProperty> </MyUserControl> instead of: <MyUserControl id="myusercontrol" runat="server" MyUrlProperty="http://myurl.com/" /> which can't be casted from System.String to System.Uri

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  • gtk-sharp-2.0 hide/show external applications(processes)

    - by ziuciek
    Hi, maybe the topic isn't quite precise.. i want to write in c# (gtk#-2.0) an app which opens another app hidden and later shows that app. For now i know only how to open hidden app... in windows...: using System; using System.Collections.Generic; using System.Linq; using System.Text; using System.Diagnostics; namespace do_kasacji { class Program { static void Main(string[] args) { ProcessStartInfo info = new ProcessStartInfo(); info.WindowStyle = ProcessWindowStyle.Minimized; info.FileName = "notepad"; using (Process pr = Process.Start(info)) { pr.WaitForExit(); } } } } Anyone knows how to change it so hat it would run in linux?

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  • question about Littles Law

    - by davit-datuashvili
    I know that Little's Law states (paraphrased): the average number of things in a system is the product of the average rate at which things leave the system and the average time each one spends in the system, or: n=x*(r+z); x-throughput r-response time z-think time r+z - average response time now i have question about a problem from programming pearls: Suppose that system makes 100 disk accesses to process a transaction (although some systems require fewer, some systems will require several hundred disk access per transaction). How many transactions per hour per disk can the system handle? please help

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  • AutoMapper is not working for a Container class

    - by rboarman
    Hello, I have an AutoMapper issue that has been driving me crazy for way too long now. A similar question was also posted on the AutoMapper user site but has not gotten much love. The summary is that I have a container class that holds a Dictionary of components. The components are a derived object of a common base class. I also have a parallel structure that I am using as DTO objects to which I want to map. The error that gets generated seems to say that the mapper cannot map between two of the classes that I have included in the CreateMap calls. I think the error has to do with the fact that I have a Dictionary of objects that are not part of the container‘s hierarchy. I apologize in advance for the length of the code below. My simple test cases work. Needless to say, it’s only the more complex case that is failing. Here are the classes: #region Dto objects public class ComponentContainerDTO { public Dictionary<string, ComponentDTO> Components { get; set; } public ComponentContainerDTO() { this.Components = new Dictionary<string, ComponentDTO>(); } } public class EntityDTO : ComponentContainerDTO { public int Id { get; set; } } public class ComponentDTO { public EntityDTO Owner { get; set; } public int Id { get; set; } public string Name { get; set; } public string ComponentType { get; set; } } public class HealthDTO : ComponentDTO { public decimal CurrentHealth { get; set; } } public class PhysicalLocationDTO : ComponentDTO { public Point2D Location { get; set; } } #endregion #region Domain objects public class ComponentContainer { public Dictionary<string, Component> Components { get; set; } public ComponentContainer() { this.Components = new Dictionary<string, Component>(); } } public class Entity : ComponentContainer { public int Id { get; set; } } public class Component { public Entity Owner { get; set; } public int Id { get; set; } public string Name { get; set; } public string ComponentType { get; set; } } public class Health : Component { public decimal CurrentHealth { get; set; } } public struct Point2D { public decimal X; public decimal Y; public Point2D(decimal x, decimal y) { X = x; Y = y; } } public class PhysicalLocation : Component { public Point2D Location { get; set; } } #endregion The code: var entity = new Entity() { Id = 1 }; var healthComponent = new Health() { CurrentHealth = 100, Owner = entity, Name = "Health", Id = 2 }; entity.Components.Add("1", healthComponent); var locationComponent = new PhysicalLocation() { Location = new Point2D() { X = 1, Y = 2 }, Owner = entity, Name = "PhysicalLocation", Id = 3 }; entity.Components.Add("2", locationComponent); Mapper.CreateMap<ComponentContainer, ComponentContainerDTO>() .Include<Entity, EntityDTO>(); Mapper.CreateMap<Entity, EntityDTO>(); Mapper.CreateMap<Component, ComponentDTO>() .Include<Health, HealthDTO>() .Include<PhysicalLocation, PhysicalLocationDTO>(); Mapper.CreateMap<Component, ComponentDTO>(); Mapper.CreateMap<Health, HealthDTO>(); Mapper.CreateMap<PhysicalLocation, PhysicalLocationDTO>(); Mapper.AssertConfigurationIsValid(); var targetEntity = Mapper.Map<Entity, EntityDTO>(entity); The error when I call Map() (abbreviated stack crawls): AutoMapper.AutoMapperMappingException was unhandled Message=Trying to map MapperTest1.Entity to MapperTest1.EntityDTO. Using mapping configuration for MapperTest1.Entity to MapperTest1.EntityDTO Exception of type 'AutoMapper.AutoMapperMappingException' was thrown. Source=AutoMapper StackTrace: at AutoMapper.MappingEngine.AutoMapper.IMappingEngineRunner.Map(ResolutionContext context) . . . InnerException: AutoMapper.AutoMapperMappingException Message=Trying to map System.Collections.Generic.Dictionary`2[[System.String, mscorlib, Version=4.0.0.0, Culture=neutral, PublicKeyToken=b77a5c561934e089],[MapperTest1.Component, ElasticTest1, Version=1.0.0.0, Culture=neutral, PublicKeyToken=null]] to System.Collections.Generic.Dictionary`2[[System.String, mscorlib, Version=4.0.0.0, Culture=neutral, PublicKeyToken=b77a5c561934e089],[MapperTest1.ComponentDTO, ElasticTest1, Version=1.0.0.0, Culture=neutral, PublicKeyToken=null]]. Using mapping configuration for MapperTest1.Entity to MapperTest1.EntityDTO Destination property: Components Exception of type 'AutoMapper.AutoMapperMappingException' was thrown. Source=AutoMapper StackTrace: at AutoMapper.Mappers.TypeMapObjectMapperRegistry.PropertyMapMappingStrategy.MapPropertyValue(ResolutionContext context, IMappingEngineRunner mapper, Object mappedObject, PropertyMap propertyMap) . . InnerException: AutoMapper.AutoMapperMappingException Message=Trying to map System.Collections.Generic.Dictionary`2[[System.String, mscorlib, Version=4.0.0.0, Culture=neutral, PublicKeyToken=b77a5c561934e089],[MapperTest1.Component, ElasticTest1, Version=1.0.0.0, Culture=neutral, PublicKeyToken=null]] to System.Collections.Generic.Dictionary`2[[System.String, mscorlib, Version=4.0.0.0, Culture=neutral, PublicKeyToken=b77a5c561934e089],[MapperTest1.ComponentDTO, ElasticTest1, Version=1.0.0.0, Culture=neutral, PublicKeyToken=null]]. Using mapping configuration for MapperTest1.Entity to MapperTest1.EntityDTO Destination property: Components Exception of type 'AutoMapper.AutoMapperMappingException' was thrown. Source=AutoMapper StackTrace: at AutoMapper.MappingEngine.AutoMapper.IMappingEngineRunner.Map(ResolutionContext context) . InnerException: AutoMapper.AutoMapperMappingException Message=Trying to map MapperTest1.Component to MapperTest1.ComponentDTO. Using mapping configuration for MapperTest1.Health to MapperTest1.HealthDTO Destination property: Components Exception of type 'AutoMapper.AutoMapperMappingException' was thrown. Source=AutoMapper StackTrace: at AutoMapper.MappingEngine.AutoMapper.IMappingEngineRunner.Map(ResolutionContext context) . . InnerException: AutoMapper.AutoMapperMappingException Message=Trying to map System.Decimal to System.Decimal. Using mapping configuration for MapperTest1.Health to MapperTest1.HealthDTO Destination property: CurrentHealth Exception of type 'AutoMapper.AutoMapperMappingException' was thrown. Source=AutoMapper StackTrace: at AutoMapper.Mappers.TypeMapObjectMapperRegistry.PropertyMapMappingStrategy.MapPropertyValue(ResolutionContext context, IMappingEngineRunner mapper, Object mappedObject, PropertyMap propertyMap) . . InnerException: System.InvalidCastException Message=Unable to cast object of type 'MapperTest1.ComponentDTO' to type 'MapperTest1.HealthDTO'. Source=Anonymously Hosted DynamicMethods Assembly StackTrace: at SetCurrentHealth(Object , Object ) . . Thank you in advance. Rick

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  • Traditional IO vs memory-mapped

    - by Senne
    I'm trying to illustrate the difference in performance between traditional IO and memory mapped files in java to students. I found an example somewhere on internet but not everything is clear to me, I don't even think all steps are nececery. I read a lot about it here and there but I'm not convinced about a correct implementation of neither of them. The code I try to understand is: public class FileCopy{ public static void main(String args[]){ if (args.length < 1){ System.out.println(" Wrong usage!"); System.out.println(" Correct usage is : java FileCopy <large file with full path>"); System.exit(0); } String inFileName = args[0]; File inFile = new File(inFileName); if (inFile.exists() != true){ System.out.println(inFileName + " does not exist!"); System.exit(0); } try{ new FileCopy().memoryMappedCopy(inFileName, inFileName+".new" ); new FileCopy().customBufferedCopy(inFileName, inFileName+".new1"); }catch(FileNotFoundException fne){ fne.printStackTrace(); }catch(IOException ioe){ ioe.printStackTrace(); }catch (Exception e){ e.printStackTrace(); } } public void memoryMappedCopy(String fromFile, String toFile ) throws Exception{ long timeIn = new Date().getTime(); // read input file RandomAccessFile rafIn = new RandomAccessFile(fromFile, "rw"); FileChannel fcIn = rafIn.getChannel(); ByteBuffer byteBuffIn = fcIn.map(FileChannel.MapMode.READ_WRITE, 0,(int) fcIn.size()); fcIn.read(byteBuffIn); byteBuffIn.flip(); RandomAccessFile rafOut = new RandomAccessFile(toFile, "rw"); FileChannel fcOut = rafOut.getChannel(); ByteBuffer writeMap = fcOut.map(FileChannel.MapMode.READ_WRITE,0,(int) fcIn.size()); writeMap.put(byteBuffIn); long timeOut = new Date().getTime(); System.out.println("Memory mapped copy Time for a file of size :" + (int) fcIn.size() +" is "+(timeOut-timeIn)); fcOut.close(); fcIn.close(); } static final int CHUNK_SIZE = 100000; static final char[] inChars = new char[CHUNK_SIZE]; public static void customBufferedCopy(String fromFile, String toFile) throws IOException{ long timeIn = new Date().getTime(); Reader in = new FileReader(fromFile); Writer out = new FileWriter(toFile); while (true) { synchronized (inChars) { int amountRead = in.read(inChars); if (amountRead == -1) { break; } out.write(inChars, 0, amountRead); } } long timeOut = new Date().getTime(); System.out.println("Custom buffered copy Time for a file of size :" + (int) new File(fromFile).length() +" is "+(timeOut-timeIn)); in.close(); out.close(); } } When exactly is it nececary to use RandomAccessFile? Here it is used to read and write in the memoryMappedCopy, is it actually nececary just to copy a file at all? Or is it a part of memorry mapping? In customBufferedCopy, why is synchronized used here? I also found a different example that -should- test the performance between the 2: public class MappedIO { private static int numOfInts = 4000000; private static int numOfUbuffInts = 200000; private abstract static class Tester { private String name; public Tester(String name) { this.name = name; } public long runTest() { System.out.print(name + ": "); try { long startTime = System.currentTimeMillis(); test(); long endTime = System.currentTimeMillis(); return (endTime - startTime); } catch (IOException e) { throw new RuntimeException(e); } } public abstract void test() throws IOException; } private static Tester[] tests = { new Tester("Stream Write") { public void test() throws IOException { DataOutputStream dos = new DataOutputStream( new BufferedOutputStream( new FileOutputStream(new File("temp.tmp")))); for(int i = 0; i < numOfInts; i++) dos.writeInt(i); dos.close(); } }, new Tester("Mapped Write") { public void test() throws IOException { FileChannel fc = new RandomAccessFile("temp.tmp", "rw") .getChannel(); IntBuffer ib = fc.map( FileChannel.MapMode.READ_WRITE, 0, fc.size()) .asIntBuffer(); for(int i = 0; i < numOfInts; i++) ib.put(i); fc.close(); } }, new Tester("Stream Read") { public void test() throws IOException { DataInputStream dis = new DataInputStream( new BufferedInputStream( new FileInputStream("temp.tmp"))); for(int i = 0; i < numOfInts; i++) dis.readInt(); dis.close(); } }, new Tester("Mapped Read") { public void test() throws IOException { FileChannel fc = new FileInputStream( new File("temp.tmp")).getChannel(); IntBuffer ib = fc.map( FileChannel.MapMode.READ_ONLY, 0, fc.size()) .asIntBuffer(); while(ib.hasRemaining()) ib.get(); fc.close(); } }, new Tester("Stream Read/Write") { public void test() throws IOException { RandomAccessFile raf = new RandomAccessFile( new File("temp.tmp"), "rw"); raf.writeInt(1); for(int i = 0; i < numOfUbuffInts; i++) { raf.seek(raf.length() - 4); raf.writeInt(raf.readInt()); } raf.close(); } }, new Tester("Mapped Read/Write") { public void test() throws IOException { FileChannel fc = new RandomAccessFile( new File("temp.tmp"), "rw").getChannel(); IntBuffer ib = fc.map( FileChannel.MapMode.READ_WRITE, 0, fc.size()) .asIntBuffer(); ib.put(0); for(int i = 1; i < numOfUbuffInts; i++) ib.put(ib.get(i - 1)); fc.close(); } } }; public static void main(String[] args) { for(int i = 0; i < tests.length; i++) System.out.println(tests[i].runTest()); } } I more or less see whats going on, my output looks like this: Stream Write: 653 Mapped Write: 51 Stream Read: 651 Mapped Read: 40 Stream Read/Write: 14481 Mapped Read/Write: 6 What is makeing the Stream Read/Write so unbelievably long? And as a read/write test, to me it looks a bit pointless to read the same integer over and over (if I understand well what's going on in the Stream Read/Write) Wouldn't it be better to read int's from the previously written file and just read and write ints on the same place? Is there a better way to illustrate it? I've been breaking my head about a lot of these things for a while and I just can't get the whole picture..

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  • Delaying NIS & NFS startup till after network interface is fully ready on Fedora 17

    - by obmarg
    I've recently set up a fedora 17 server for our network, and I've been having trouble getting the NIS service to work on startup. Here's some logs from the system: Aug 21 12:57:12 cairnwell ypbind-pre-setdomain[718]: Setting NIS domain: 'indigo-nis' (environment variable) Aug 21 12:57:13 cairnwell ypbind: Binding NIS service Aug 21 12:57:13 cairnwell rpc.statd[730]: Unable to prune capability 0 from bounding set: Operation not permitted Aug 21 12:57:13 cairnwell systemd[1]: nfs-lock.service: control process exited, code=exited status=1 Aug 21 12:57:13 cairnwell systemd[1]: Unit nfs-lock.service entered failed state. Aug 21 12:57:14 cairnwell setroubleshoot: SELinux is preventing /usr/sbin/rpc.statd from using the setpcap capability. For complete SELinux messages. run sealert -l 024bba8a-b0ef-43dc-b195-5c9a2d4c4d41 Aug 21 12:57:15 cairnwell kernel: [ 18.822282] bnx2 0000:02:00.0: em1: NIC Copper Link is Up, 1000 Mbps full duplex Aug 21 12:57:15 cairnwell kernel: [ 18.822925] ADDRCONF(NETDEV_CHANGE): em1: link becomes ready Aug 21 12:57:15 cairnwell NetworkManager[621]: <info> (em1): carrier now ON (device state 20) Aug 21 12:57:15 cairnwell NetworkManager[621]: <info> (em1): device state change: unavailable -> disconnected (reason 'carrier-changed') [20 30 40] Aug 21 12:57:15 cairnwell NetworkManager[621]: <info> Auto-activating connection 'System em1'. Aug 21 12:57:15 cairnwell NetworkManager[621]: <info> Activation (em1) starting connection 'System em1' Aug 21 12:57:15 cairnwell NetworkManager[621]: <info> (em1): device state change: disconnected -> prepare (reason 'none') [30 40 0] ....... Aug 21 12:57:19 cairnwell sendmail[790]: YPBINDPROC_DOMAIN: Domain not bound Aug 21 12:57:26 cairnwell sendmail[790]: YPBINDPROC_DOMAIN: Domain not bound Aug 21 12:57:31 cairnwell sendmail[790]: YPBINDPROC_DOMAIN: Domain not bound Aug 21 12:57:35 cairnwell sendmail[790]: YPBINDPROC_DOMAIN: Domain not bound Aug 21 12:58:00 cairnwell ypbind: Binding took 47 seconds Aug 21 12:58:00 cairnwell ypbind: NIS server for domain indigo-nis is not responding. Aug 21 12:58:01 cairnwell ypbind: Killing ypbind with PID 733. Aug 21 12:58:01 cairnwell ypbind-post-waitbind[734]: /usr/lib/ypbind/ypbind-post-waitbind: line 51: kill: SIGTERM: invalid signal specification Aug 21 12:58:01 cairnwell systemd[1]: ypbind.service: control process exited, code=exited status=1 Aug 21 12:58:01 cairnwell systemd[1]: Unit ypbind.service entered failed state. By the looks of these logs the ypbind service is starting up at 12:57:12 but the network interface isn't coming up till 12:57:15. My guess is that this is causing ypbind to time out when trying to connect. As a knock-on effect the NIS failure is causing problems with NFS which is no longer able to map UIDs properly. This problem doesn't seem to be fixed by actually starting ypbind etc. so I've had to set all my NFS shares to noauto. I have tried manually adding NETWORKDELAY and NETWORKWAIT in /etc/sysconfig/network and also running systemctl enable NetworkManager-wait-online.service as I've seen suggested in some places, but neither of these have had any effect. It is relatively easy to fix manually by restarting ypbind & mounting NFS shares after the network has started up, but it's less than ideal to have to do this every time the server has been rebooted. Does anyone know of an easy (and preferably hack-free) way of delaying the ypbind startup till after the network interface is fully ready?

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  • DHCPDISCOVER requests from an off-by-one MAC address

    - by Aleksandr Levchuk
    In a Linux DHCP server I'm getting a bunch of these log lines: dhcpd: DHCPDISCOVER from 00:30:48:fe:5c:9c via eth1: network 192.168.2.0/24: no free leases I don't have any machines with 00:30:48:fe:5c:9c and I don't intend to give out an IP to 00:30:48:fe:5c:9c (whatever that could be). I tracked down the server that this is coming from and killed all the DHCP clients that were running but the DHCPDISCOVER requests do not stop. I can prove that this is the sending server by pulling the Ethernet cable - the requests stop. The strange thing is that the sending server only has 2 interfaces which are: 00:30:48:fe:5c:9a 00:30:48:fe:5c:9b What can be the cause of the off-by-one address? Who could be sending the requests? Details On the DHCP client: root@n34:~# ip link 1: lo: <LOOPBACK,UP,LOWER_UP> mtu 16436 qdisc noqueue state UNKNOWN link/loopback 00:00:00:00:00:00 brd 00:00:00:00:00:00 2: eth0: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc mq state UP qlen 100 link/ether 00:30:48:fe:5c:9a brd ff:ff:ff:ff:ff:ff 3: eth1: <NO-CARRIER,BROADCAST,MULTICAST,UP> mtu 1500 qdisc mq state DOWN qlen 1000 link/ether 00:30:48:fe:5c:9b brd ff:ff:ff:ff:ff:ff 4: ib0: <BROADCAST,MULTICAST> mtu 2044 qdisc noop state DOWN qlen 256 link/infiniband 80:00:00:48:fe:80:00:00:00:00:00:00:00:02:c9:03:00:08:81:9f brd 00:ff:ff:ff:ff:12:40:1b:ff:ff:00:00:00:00:00:00:ff:ff:ff:ff 5: ib1: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 2044 qdisc pfifo_fast state UP qlen 256 link/infiniband 80:00:00:49:fe:80:00:00:00:00:00:00:00:02:c9:03:00:08:81:a0 brd 00:ff:ff:ff:ff:12:40:1b:ff:ff:00:00:00:00:00:00:ff:ff:ff:ff Same info: root@n34:~# ifconfig -a eth0 Link encap:Ethernet HWaddr 00:30:48:fe:5c:9a inet addr:192.168.2.234 Bcast:192.168.2.255 Mask:255.255.255.0 inet6 addr: fe80::230:48ff:fefe:5c9a/64 Scope:Link UP BROADCAST RUNNING MULTICAST MTU:1500 Metric:1 RX packets:72544 errors:0 dropped:0 overruns:0 frame:0 TX packets:152773 errors:0 dropped:0 overruns:0 carrier:0 collisions:0 txqueuelen:100 RX bytes:4908592 (4.6 MiB) TX bytes:89815782 (85.6 MiB) Memory:dfd60000-dfd80000 eth1 Link encap:Ethernet HWaddr 00:30:48:fe:5c:9b UP BROADCAST MULTICAST MTU:1500 Metric:1 RX packets:0 errors:0 dropped:0 overruns:0 frame:0 TX packets:0 errors:0 dropped:0 overruns:0 carrier:0 collisions:0 txqueuelen:1000 RX bytes:0 (0.0 B) TX bytes:0 (0.0 B) Memory:dfde0000-dfe00000 ib0 Link encap:UNSPEC HWaddr 80-00-00-48-FE-80-00-00-00-00-00-00-00-00-00-00 BROADCAST MULTICAST MTU:2044 Metric:1 RX packets:0 errors:0 dropped:0 overruns:0 frame:0 TX packets:0 errors:0 dropped:0 overruns:0 carrier:0 collisions:0 txqueuelen:256 RX bytes:0 (0.0 B) TX bytes:0 (0.0 B) ib1 Link encap:UNSPEC HWaddr 80-00-00-49-FE-80-00-00-00-00-00-00-00-00-00-00 inet addr:192.168.3.234 Bcast:192.168.3.255 Mask:255.255.255.0 inet6 addr: fe80::202:c903:8:81a0/64 Scope:Link UP BROADCAST RUNNING MULTICAST MTU:2044 Metric:1 RX packets:1330 errors:0 dropped:0 overruns:0 frame:0 TX packets:255 errors:0 dropped:5 overruns:0 carrier:0 collisions:0 txqueuelen:256 RX bytes:716415 (699.6 KiB) TX bytes:17584 (17.1 KiB) lo Link encap:Local Loopback inet addr:127.0.0.1 Mask:255.0.0.0 inet6 addr: ::1/128 Scope:Host UP LOOPBACK RUNNING MTU:16436 Metric:1 RX packets:8 errors:0 dropped:0 overruns:0 frame:0 TX packets:8 errors:0 dropped:0 overruns:0 carrier:0 collisions:0 txqueuelen:0 RX bytes:560 (560.0 B) TX bytes:560 (560.0 B) The nodes were imaged with Perseus which uses kexec instead of rebooting.

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  • Windows 7: How to place SuperFetch cache on an SSD?

    - by Ian Boyd
    I'm thinking of adding a solid state drive (SSD) to my existing Windows 7 installation. I know I can (and should) move my paging file to the SSD: Should the pagefile be placed on SSDs? Yes. Most pagefile operations are small random reads or larger sequential writes, both of which are types of operations that SSDs handle well. In looking at telemetry data from thousands of traces and focusing on pagefile reads and writes, we find that Pagefile.sys reads outnumber pagefile.sys writes by about 40 to 1, Pagefile.sys read sizes are typically quite small, with 67% less than or equal to 4 KB, and 88% less than 16 KB. Pagefile.sys writes are relatively large, with 62% greater than or equal to 128 KB and 45% being exactly 1 MB in size. In fact, given typical pagefile reference patterns and the favorable performance characteristics SSDs have on those patterns, there are few files better than the pagefile to place on an SSD. What I don't know is if I even can put a SuperFetch cache (i.e. ReadyBoost cache) on the solid state drive. I want to get the benefit of Windows being able to cache gigabytes of frequently accessed data on a relativly small (e.g. 30GB) solid state drive. This is exactly what SuperFetch+ReadyBoost (or SuperFetch+ReadyDrive) was designed for. Will Windows offer (or let) me place a ReadyBoost cache on a solid state flash drive connected via SATA? A problem with the ReadyBoost cache over the ReadyDrive cache is that the ReadyBoost cache does not survive between reboots. The cache is encrypted with a per-session key, making its existing contents unusable during boot and SuperFetch pre-fetching during login. Update One I know that Windows Vista limited you to only one ReadyBoost.sfcache file (I do not know if Windows 7 removed that limitation): Q: Can use use multiple devices for EMDs? A: Nope. We've limited Vista to one ReadyBoost per machine Q: Why just one device? A: Time and quality. Since this is the first revision of the feature, we decided to focus on making the single device exceptional, without the difficulties of managing multiple caches. We like the idea, though, and it's under consideration for future versions. I also know that the 4GB limit on the cache file was a limitation of the FAT filesystem used on most USB sticks - an SSD drive would be formatted with NTFS: Q: What's the largest amount of flash that I can use for ReadyBoost? A: You can use up to 4GB of flash for ReadyBoost (which turns out to be 8GB of cache w/ the compression) Q: Why can't I use more than 4GB of flash? A: The FAT32 filesystem limits our ReadyBoost.sfcache file to 4GB Can a ReadyBoost cache on an NTFS volume be larger than 4GB? Update Two The ReadyBoost cache is encrypted with a per-boot session key. This means that the cache has to be re-built after each boot, and cannot be used to help speed boot times, or latency from login to usable. Windows ReadyDrive technology takes advantage of non-volatile (NV) memory (i.e. flash) that is incorporated with some hybrid hard drives. This flash cache can be used to help Windows boot, or resume from hibernate faster. Will Windows 7 use an internal SSD drive as a ReadyBoost/*ReadyDrive*/SuperFetch cache? Is it possible to make Windows store a SuperFetch cache (i.e. ReadyBoost) on a non-removable SSD? Is it possible to not encrypt the ReadyBoost cache, and if so will Windows 7 use the cache at boot time? See also SuperUser.com: ReadyBoost + SSD = ? Windows 7 - ReadyBoost & SSD drives? Support and Q&A for Solid-State Drives Using SDD as a cache for HDD, is there a solution? Performance increase using SSD for paging/fetch/cache or ReadyBoost? (Win7) Windows 7 To Boost SSD Performance How to Disable Nonvolatile Caching

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  • Expert iptables help needed?

    - by Asad Moeen
    After a detailed analysis, I collected these details. I am under a UDP Flood which is more of application dependent. I run a Game-Server and an attacker is flooding me with "getstatus" query which makes the GameServer respond by making the replies to the query which cause output to the attacker's IP as high as 30mb/s and server lag. Here are the packet details, Packet starts with 4 bytes 0xff and then getstatus. Theoretically, the packet is like "\xff\xff\xff\xffgetstatus " Now that I've tried a lot of iptables variations like state and rate-limiting along side but those didn't work. Rate Limit works good but only when the Server is not started. As soon as the server starts, no iptables rule seems to block it. Anyone else got more solutions? someone asked me to contact the provider and get it done at the Network/Router but that looks very odd and I believe they might not do it since that would also affect other clients. Responding to all those answers, I'd say: Firstly, its a VPS so they can't do it for me. Secondly, I don't care if something is coming in but since its application generated so there has to be a OS level solution to block the outgoing packets. At least the outgoing ones must be stopped. Secondly, its not Ddos since just 400kb/s input generates 30mb/s output from my GameServer. That never happens in a D-dos. Asking the provider/hardware level solution should be used in that case but this one is different. And Yes, Banning his IP stops the flood of outgoing packets but he has many more IP-Addresses as he spoofs his original so I just need something to block him automatically. Even tried a lot of Firewalls but as you know they are just front-ends to iptables so if something doesn't work on iptables, what would the firewalls do? These were the rules I tried, iptables -A INPUT -p udp -m state --state NEW -m recent --set --name DDOS --rsource iptables -A INPUT -p udp -m state --state NEW -m recent --update --seconds 1 --hitcount 5 --name DDOS --rsource -j DROP It works for the attacks on un-used ports but when the server is listening and responding to the incoming queries by the attacker, it never works. Okay Tom.H, your rules were working when I modified them somehow like this: iptables -A INPUT -p udp -m length --length 1:1024 -m recent --set --name XXXX --rsource iptables -A INPUT -p udp -m string --string "xxxxxxxxxx" --algo bm --to 65535 -m recent --update --seconds 1 --hitcount 15 --name XXXX --rsource -j DROP They worked for about 3 days very good where the string "xxxxxxxxx" would be rate-limited, blocked if someone flooded and also didn't affect the clients. But just today, I tried updating the chain to try to remove a previously blocked IP so for that I had to flush the chain and restore this rule ( iptables -X and iptables -F ), some clients were already connected to servers including me. So restoring the rules now would also block some of the clients string completely while some are not affected. So does this mean I need to restart the server or why else would this happen because the last time the rules were working, there was no one connected?

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  • How to place SuperFetch cache on an SSD?

    - by Ian Boyd
    I'm thinking of adding a solid state drive (SSD) to my existing Windows 7 installation. I know I can (and should) move my paging file to the SSD: Should the pagefile be placed on SSDs? Yes. Most pagefile operations are small random reads or larger sequential writes, both of which are types of operations that SSDs handle well. In looking at telemetry data from thousands of traces and focusing on pagefile reads and writes, we find that Pagefile.sys reads outnumber pagefile.sys writes by about 40 to 1, Pagefile.sys read sizes are typically quite small, with 67% less than or equal to 4 KB, and 88% less than 16 KB. Pagefile.sys writes are relatively large, with 62% greater than or equal to 128 KB and 45% being exactly 1 MB in size. In fact, given typical pagefile reference patterns and the favorable performance characteristics SSDs have on those patterns, there are few files better than the pagefile to place on an SSD. What I don't know is if I even can put a SuperFetch cache (i.e. ReadyBoost cache) on the solid state drive. I want to get the benefit of Windows being able to cache gigabytes of frequently accessed data on a relativly small (e.g. 30GB) solid state drive. This is exactly what SuperFetch+ReadyBoost (or SuperFetch+ReadyDrive) was designed for. Will Windows offer (or let) me place a ReadyBoost cache on a solid state flash drive connected via SATA? A problem with the ReadyBoost cache over the ReadyDrive cache is that the ReadyBoost cache does not survive between reboots. The cache is encrypted with a per-session key, making its existing contents unusable during boot and SuperFetch pre-fetching during login. Update One I know that Windows Vista limited you to only one ReadyBoost.sfcache file (I do not know if Windows 7 removed that limitation): Q: Can use use multiple devices for EMDs? A: Nope. We've limited Vista to one ReadyBoost per machine Q: Why just one device? A: Time and quality. Since this is the first revision of the feature, we decided to focus on making the single device exceptional, without the difficulties of managing multiple caches. We like the idea, though, and it's under consideration for future versions. I also know that the 4GB limit on the cache file was a limitation of the FAT filesystem used on most USB sticks - an SSD drive would be formatted with NTFS: Q: What's the largest amount of flash that I can use for ReadyBoost? A: You can use up to 4GB of flash for ReadyBoost (which turns out to be 8GB of cache w/ the compression) Q: Why can't I use more than 4GB of flash? A: The FAT32 filesystem limits our ReadyBoost.sfcache file to 4GB Can a ReadyBoost cache on an NTFS volume be larger than 4GB? Update Two The ReadyBoost cache is encrypted with a per-boot session key. This means that the cache has to be re-built after each boot, and cannot be used to help speed boot times, or latency from login to usable. Windows ReadyDrive technology takes advantage of non-volatile (NV) memory (i.e. flash) that is incorporated with some hybrid hard drives. This flash cache can be used to help Windows boot, or resume from hibernate faster. Will Windows 7 use an internal SSD drive as a ReadyBoost/*ReadyDrive*/SuperFetch cache? Is it possible to make Windows store a SuperFetch cache (i.e. ReadyBoost) on a non-removable SSD? Is it possible to not encrypt the ReadyBoost cache, and if so will Windows 7 use the cache at boot time? See also SuperUser.com: ReadyBoost + SSD = ? Windows 7 - ReadyBoost & SSD drives? Support and Q&A for Solid-State Drives Using SDD as a cache for HDD, is there a solution? Performance increase using SSD for paging/fetch/cache or ReadyBoost? (Win7) Windows 7 To Boost SSD Performance How to Disable Nonvolatile Caching

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