blocking

问题 I'm using Firebug 1.5.2 and while testing a site before production release i can see a huge amount of time consumed by 'Blocking' parts of the requests. What exactly does the 'Blocking' mean? 回答1: "Blocking" previously (earlier versions of FireBug) was called "Queuing". It actually means that request is sitting in queue waiting for available connection. As far as I know number of persistent connections by default is limited in last versions of Firefox to 6, IE8 also 6. Earlier it was only 2.

问题 I don't really know how to formulate my question this time... I have my application with a QDialog as a main window. The application is getting different values like temperature, humidity and so on from a remote machine. For development I added a group box with different widgets to simulate these values. I have different limits for throwing warnings and alarms to the user. For example if temperature rises over 30°C then I open a QMessageBox with the request time (the application does polling

问题 This question is not about designs or patterns and which to use. The heart of this question is about what is happening regarding threads and blocking. This example is to apply to any blocking method that is designed to perform the same action continuously. In this case it is a blocking read or write on a networkstream. Is there any appreciable difference behind the scenes as to threading and performance between the methods? My assumption is that each of the methods below creates a thread or

问题 I am currently programming a server in C that communicates over sockets using TCP. The client is supposed to send {filename\n} + {file contents\n} and the server will store that information and then send a response on success. However, we can't be sure the client will actually send the proper information in a structured protocol. Often in simpler situations, we know a specified amount of bytes to be sent before and can wait until that specified number has been reached. In this case, we don't

问题 I can write non-blocking I/O in Node.js very easily. It's what the entire library is set up for. But any computation done is blocking. Any message passing over event emitters are blocking. For example, emitting events are resolved immediately and are thus blocking: var e = new process.EventEmitter; e.on("foo", function() { console.log("event"); }); process.nextTick(function() { console.log("next tick"); }); setTimeout(function() { console.log("timeout"); }, 0); e.emit("foo"); > event > next

问题 I have the classic problem of a thread pushing events to the incoming queue of a second thread. Only this time, I am very interested about performance. What I want to achieve is: I want concurrent access to the queue, the producer pushing, the receiver poping. When the queue is empty, I want the consumer to block to the queue, waiting for the producer. My first idea was to use a LinkedBlockingQueue , but I soon realized that it is not concurrent and the performance suffered. On the other hand

问题 I need to wait for a response from a SOAP webservice, I am calling via a NSURLConnection as I need to manipulate the data being returned and then return it from my class to the calling class.. Here is my code: #import <Foundation/Foundation.h> @interface UsersBLL : NSObject { NSMutableData *webData; NSMutableString *soapResults; NSXMLParser *xmlParser; BOOL *recordResults; NSNumber *EmailCount; } @property(nonatomic, retain) NSMutableData *webData; @property(nonatomic, retain) NSMutableString

问题 I need to wait for a response from a SOAP webservice, I am calling via a NSURLConnection as I need to manipulate the data being returned and then return it from my class to the calling class.. Here is my code: #import <Foundation/Foundation.h> @interface UsersBLL : NSObject { NSMutableData *webData; NSMutableString *soapResults; NSXMLParser *xmlParser; BOOL *recordResults; NSNumber *EmailCount; } @property(nonatomic, retain) NSMutableData *webData; @property(nonatomic, retain) NSMutableString

问题 I have my main process send pthread_cancel to another thread which is waiting for a condition to happen with cond_wait(&condition) . On the pthread_cancel they are saying : Deferred cancel ability means that cancellation will be delayed until the thread next calls a function that is a cancellation point. But often those function are blocking function. Then my question is the thread cancelled only after that thread has been unblock (in my example by a broadcast or a signal) or it would see

问题 I have my main process send pthread_cancel to another thread which is waiting for a condition to happen with cond_wait(&condition) . On the pthread_cancel they are saying : Deferred cancel ability means that cancellation will be delayed until the thread next calls a function that is a cancellation point. But often those function are blocking function. Then my question is the thread cancelled only after that thread has been unblock (in my example by a broadcast or a signal) or it would see