Search Results

Search found 5945 results on 238 pages for 'green threads'.

Page 37/238 | < Previous Page | 33 34 35 36 37 38 39 40 41 42 43 44  | Next Page >

  • Regular expression test can't decide between true and false (JavaScript)

    - by nw
    I get this behavior in both Chrome (Developer Tools) and Firefox (Firebug). Note the regex test returns alternating true/false values: > var re = /.*?\bbl.*\bgr.*/gi; undefined > re /.*?\\bbl.*\\bgr.*/gi > re.test("Blue-Green"); true > re.test("Blue-Green"); false > re.test("Blue-Green"); true > re.test("Blue-Green"); false However, testing the same regex as a literal: > /.*?\bbl.*\bgr.*/gi.test("Blue-Green"); true > /.*?\bbl.*\bgr.*/gi.test("Blue-Green"); true > /.*?\bbl.*\bgr.*/gi.test("Blue-Green"); true > /.*?\bbl.*\bgr.*/gi.test("Blue-Green"); true I can't explain this and it's making debugging very difficult. Can anyone explain this behavior?

    Read the article

  • Why is my multithreaded Java program not maxing out all my cores on my machine?

    - by James B
    Hi, I have a program that starts up and creates an in-memory data model and then creates a (command-line-specified) number of threads to run several string checking algorithms against an input set and that data model. The work is divided amongst the threads along the input set of strings, and then each thread iterates the same in-memory data model instance (which is never updated again, so there are no synchronization issues). I'm running this on a Windows 2003 64-bit server with 2 quadcore processors, and from looking at Windows task Manager they aren't being maxed-out, (nor are they looking like they are being particularly taxed) when I run with 10 threads. Is this normal behaviour? It appears that 7 threads all complete a similar amount of work in a similar amount of time, so would you recommend running with 7 threads instead? Should I run it with more threads?...Although I assume this could be detrimental as the JVM will do more context switching between the threads. Alternatively, should I run it with fewer threads? Alternatively, what would be the best tool I could use to measure this?...Would a profiling tool help me out here - indeed, is one of the several profilers better at detecting bottlenecks (assuming I have one here) than the rest? Note, the server is also running SQL Server 2005 (this may or may not be relevant), but nothing much is happening on that database when I am running my program. Note also, the threads are only doing string matching, they aren't doing any I/O or database work or anything else they may need to wait on. Thanks in advance, -James

    Read the article

  • Handling user interface in a multi-threaded application (or being forced to have a UI-only main thre

    - by Patrick
    In my application, I have a 'logging' window, which shows all the logging, warnings, errors of the application. Last year my application was still single-threaded so this worked [quite] good. Now I am introducing multithreading. I quickly noticed that it's not a good idea to update the logging window from different threads. Reading some articles on keeping the UI in the main thread, I made a communication buffer, in which the other threads are adding their logging messages, and from which the main thread takes the messages and shows them in the logging window (this is done in the message loop). Now, in a part of my application, the memory usage increases dramatically, because the separate threads are generating lots of logging messages, and the main thread cannot empty the communication buffer quickly enough. After the while the memory decreases again (if the other threads have finished their work and the main thread gradually empties the communication buffer). I solved this problem by having a maximum size on the communication buffer, but then I run into a problem in the following situation: the main thread has to perform a complex action the main thread takes some parts of the action and let's separate threads execute this while the seperate threads are executing their logic, the main thread processes the results from the other threads and continues with its work if the other threads are finished Problem is that in this situation, if the other threads perform logging, there is no UI-message loop, and so the communication buffer is filled, but not emptied. I see two solutions in solving this problem: require the main thread to do regular polling of the communication buffer only performing user interface logic in the main thread (no other logic) I think the second solution seems the best, but this may not that easy to introduce in a big application (in my case it performs mathematical simulations). Are there any other solutions or tips? Or is one of the two proposed the best, easiest, most-pragmatic solution? Thanks, Patrick

    Read the article

  • The JRockit Performance Counters

    - by Marcus Hirt
    Every now and then I get a question regarding what the attributes in the PerfCounters dynamic MBean represent. Now, all the MBeans under the oracle.jrockit.management (bea.jrockit.management pre R28) domain are part of what we call JMXMAPI (the JRockit JMX based Management API), which is unsupported. Therefore there is no official documentation for the API. I did however write a bit about JMXMAPI in my recent JRockit book, Oracle JRockit: The Definitive Guide. The information in the table below is from that book: Counter Description java.cls.loadedClasses The number of classes loaded since the start of the JVM. java.cls.unloadedClasses The number of classes unloaded since the start of the JVM. java.property.java.class.path The class path of the JVM. java.property.java.endorsed.dirs The endorsed dirs. See the Endorsed Standards Override Mechanism. java.property.java.ext.dirs The ext dirs, which are searched for jars that should be automatically put on the classpath. See the Java documentation for java.ext.dirs. java.property.java.home The root of the JDK or JRE installation. java.property.java.library.path The library path used to find user libraries. java.property.java.vm.version The JRockit version. java.rt.vmArgs The list of VM arguments. java.threads.daemon The number of running daemon threads. java.threads.live The total number of running threads. java.threads.livePeak The peak number of threads that has been running since JRockit was started. java.threads.nonDaemon The number of non-daemon threads running. java.threads.started The total number of threads started since the start of JRockit. jrockit.gc.latest.heapSize The current heap size in bytes. jrockit.gc.latest.nurserySize The current nursery size in bytes. jrockit.gc.latest.oc.compaction.time How long, in ticks, the last compaction lasted. Reset to 0 if compaction is skipped. jrockit.gc.latest.oc.heapUsedAfter Used heap at the end of the last OC, in bytes. jrockit.gc.latest.oc.heapUsedBefore Used heap at the start of the last OC, in bytes. jrockit.gc.latest.oc.number The number of OCs that have occurred so far. jrockit.gc.latest.oc.sumOfPauses The paused time for the last OC, in ticks. jrockit.gc.latest.oc.time The time the last OC took, in ticks. jrockit.gc.latest.yc.sumOfPauses The paused time for the last YC, in ticks. jrockit.gc.latest.yc.time The time the last YC took, in ticks. jrockit.gc.max.oc.individualPause The longest OC pause so far, in ticks. jrockit.gc.max.yc.individualPause The longest YC pause so far, in ticks. jrockit.gc.total.oc.compaction.externalAborted Number of aborted external compactions so far. jrockit.gc.total.oc.compaction.internalAborted Number of aborted internal compactions so far. jrockit.gc.total.oc.compaction.internalSkipped Number of skipped internal compactions so far. jrockit.gc.total.oc.compaction.time The total time spent doing compaction so far, in ticks. jrockit.gc.total.oc.ompaction.externalSkipped Number of skipped external compactions so far. jrockit.gc.total.oc.pauseTime The sum of all OC pause times so far, in ticks. jrockit.gc.total.oc.time The total time spent doing OC so far, in ticks. jrockit.gc.total.pageFaults The number of page faults that have occurred during GC so far. jrockit.gc.total.yc.pauseTime The sum of all YC pause times, in ticks. jrockit.gc.total.yc.promotedObjects The number of objects that all YCs have promoted. jrockit.gc.total.yc.promotedSize The total number of bytes that all YCs have promoted, in bytes. jrockit.gc.total.yc.time The total time spent doing YC, in ticks. oracle.ci.jit.count The number of methods JIT compiled. oracle.ci.jit.timeTotal The total time spent JIT compiling, in ticks. oracle.ci.opt.count The number of methods optimized. oracle.ci.opt.timeTotal The total time spent optimizing, in ticks. oracle.rt.counterFrequency Used to convert ticks values to seconds. Note that many of these counters are excellent choices for attributes to plot in the Management Console. Also note that many values are in ticks – to convert them to seconds, divide by the value in the oracle.rt.counterFrequency counter.

    Read the article

  • Can I query DOM Document with xpath expression from multiple threads safely?

    - by Dan
    I plan to use dom4j DOM Document as a static cache in an application where multiples threads can query the document. Taking into the account that the document itself will never change, is it safe to query it from multiple threads? I wrote the following code to test it, but I am not sure that it actually does prove that operation is safe? package test.concurrent_dom; import org.dom4j.Document; import org.dom4j.DocumentException; import org.dom4j.DocumentHelper; import org.dom4j.Element; import org.dom4j.Node; /** * Hello world! * */ public class App extends Thread { private static final String xml = "<Session>" + "<child1 attribute1=\"attribute1value\" attribute2=\"attribute2value\">" + "ChildText1</child1>" + "<child2 attribute1=\"attribute1value\" attribute2=\"attribute2value\">" + "ChildText2</child2>" + "<child3 attribute1=\"attribute1value\" attribute2=\"attribute2value\">" + "ChildText3</child3>" + "</Session>"; private static Document document; private static Element root; public static void main( String[] args ) throws DocumentException { document = DocumentHelper.parseText(xml); root = document.getRootElement(); Thread t1 = new Thread(){ public void run(){ while(true){ try { sleep(3); } catch (InterruptedException e) { e.printStackTrace(); } Node n1 = root.selectSingleNode("/Session/child1"); if(!n1.getText().equals("ChildText1")){ System.out.println("WRONG!"); } } } }; Thread t2 = new Thread(){ public void run(){ while(true){ try { sleep(3); } catch (InterruptedException e) { e.printStackTrace(); } Node n1 = root.selectSingleNode("/Session/child2"); if(!n1.getText().equals("ChildText2")){ System.out.println("WRONG!"); } } } }; Thread t3 = new Thread(){ public void run(){ while(true){ try { sleep(3); } catch (InterruptedException e) { e.printStackTrace(); } Node n1 = root.selectSingleNode("/Session/child3"); if(!n1.getText().equals("ChildText3")){ System.out.println("WRONG!"); } } } }; t1.start(); t2.start(); t3.start(); System.out.println( "Hello World!" ); } }

    Read the article

  • Is there an use case for non-blocking receive when I have threads?

    - by Gabriel Šcerbák
    I know non-blocking receive is not used as much in message passing, but still some intuition tells me, it is needed. Take for example GUI event driven applications, you need some way to wait for a message in a non-blocking way, so your program can execute some computations. One of the ways to solve this is to have a special thread with message queue. Is there some use case, where you would really need non-blocking receive even if you have threads?

    Read the article

  • Do really need a count lock on Multi threads with one CPU core?

    - by MrROY
    If i have some code looks like this(Please ignore the syntax, i want to understand it without a specified language): count = 0 def countDown(): count += 1 if __name__ == '__main__': thread1(countDown) thread2(countDown) thread3(countDown) Here i have a CPU with only one core, do i really need a lock to the variable count in case of it could be over-written by other threads. I don't know, but if the language cares a lot, please explain it under Java?C and Python, So many thanks.

    Read the article

  • locking on dictionary of structs not working between 2 threads?

    - by Rancur3p1c
    C#, .Net2.0, XP, Zen I have 2 threads accessing a shared dictionary of structures, each thread via an event. At the beginning of the event I lock the dictionary, remove some structures, and exit the lock+event. Yet somehow the 2nd thread|event is finding some of the removed structures. Conceptually I must be doing something wrong for this to be happening? I thought locking was supposed to make it thread safe?

    Read the article

  • How are the concepts of process and threads implementated in Linux kernel?

    - by Shan
    Can any one explain how are the concepts of process and threads implemented in Linux kernel ? I am looking for an intuitive explanation with some C snippets ( and important data structures) that clearly distinguishes between the two. I am just looking for the key implementation ideas I should get hold off. Essentially, I want to understand them and implement something similar in an embedded target (not supporte by any OS) in C language.

    Read the article

  • Can two or more threads iterate over the same List<t> without any problems?

    - by CodingCrapper
    Talking about System.Collections.Generic.List here. With example below can Method1 and Method2 execute and the same time, on different threads without any problems? Thanks class Test { private readonly List<MyData> _data; public Test() { _data = LoadData(); } private List<MyData> LoadData() { //Get data from dv. } public void Method1() { foreach (var list in _data) { //do something } } public void Method2() { foreach (var list in _data) { //do something } } }

    Read the article

  • Using two threads and controlling one from the other in java?

    - by sidra
    Can someone please help me out. I need to use two threads in a way that one thread will run permanently while(true) and will keep track of a positioning pointer (some random value coming in form a method). This thread has a logic, if the value equals something, it should start the new thread. And if the value does not equal it should stop the other thread. Can someone give me some code snippet (block level) about how to realize this?

    Read the article

  • Is MSDN referencing a system.thread, a worker thread, an io thread or all three?

    - by w0051977
    Please see the warning below taken from the StreamWriter class specification (http://msdn.microsoft.com/en-us/library/system.io.streamwriter.aspx): "Any public static (Shared in Visual Basic) members of this type are thread safe. Any instance members are not guaranteed to be thread safe." I understand that a W3WC process contains two thread pools i.e. worker threads and I/O threads. A worker thread could contain many threads of its own (if the application creates its own System.Thread instances). Does the warning only relate to System.Threads or does it relate to worker threads and I/O threads as well I.e. as the instance variables of the streamwriter class are not thread safe then does this mean that there would be problems if multiple worker threads access it eg if two users on two different web clients attempt to write to the log file at the same time, then could one lock out the other?

    Read the article

  • Scheduling thread tiles with C++ AMP

    - by Daniel Moth
    This post assumes you are totally comfortable with, what some of us call, the simple model of C++ AMP, i.e. you could write your own matrix multiplication. We are now ready to explore the tiled model, which builds on top of the non-tiled one. Tiling the extent We know that when we pass a grid (which is just an extent under the covers) to the parallel_for_each call, it determines the number of threads to schedule and their index values (including dimensionality). For the single-, two-, and three- dimensional cases you can go a step further and subdivide the threads into what we call tiles of threads (others may call them thread groups). So here is a single-dimensional example: extent<1> e(20); // 20 units in a single dimension with indices from 0-19 grid<1> g(e);      // same as extent tiled_grid<4> tg = g.tile<4>(); …on the 3rd line we subdivided the single-dimensional space into 5 single-dimensional tiles each having 4 elements, and we captured that result in a concurrency::tiled_grid (a new class in amp.h). Let's move on swiftly to another example, in pictures, this time 2-dimensional: So we start on the left with a grid of a 2-dimensional extent which has 8*6=48 threads. We then have two different examples of tiling. In the first case, in the middle, we subdivide the 48 threads into tiles where each has 4*3=12 threads, hence we have 2*2=4 tiles. In the second example, on the right, we subdivide the original input into tiles where each has 2*2=4 threads, hence we have 4*3=12 tiles. Notice how you can play with the tile size and achieve different number of tiles. The numbers you pick must be such that the original total number of threads (in our example 48), remains the same, and every tile must have the same size. Of course, you still have no clue why you would do that, but stick with me. First, we should see how we can use this tiled_grid, since the parallel_for_each function that we know expects a grid. Tiled parallel_for_each and tiled_index It turns out that we have additional overloads of parallel_for_each that accept a tiled_grid instead of a grid. However, those overloads, also expect that the lambda you pass in accepts a concurrency::tiled_index (new in amp.h), not an index<N>. So how is a tiled_index different to an index? A tiled_index object, can have only 1 or 2 or 3 dimensions (matching exactly the tiled_grid), and consists of 4 index objects that are accessible via properties: global, local, tile_origin, and tile. The global index is the same as the index we know and love: the global thread ID. The local index is the local thread ID within the tile. The tile_origin index returns the global index of the thread that is at position 0,0 of this tile, and the tile index is the position of the tile in relation to the overall grid. Confused? Here is an example accompanied by a picture that hopefully clarifies things: array_view<int, 2> data(8, 6, p_my_data); parallel_for_each(data.grid.tile<2,2>(), [=] (tiled_index<2,2> t_idx) restrict(direct3d) { /* todo */ }); Given the code above and the picture on the right, what are the values of each of the 4 index objects that the t_idx variables exposes, when the lambda is executed by T (highlighted in the picture on the right)? If you can't work it out yourselves, the solution follows: t_idx.global       = index<2> (6,3) t_idx.local          = index<2> (0,1) t_idx.tile_origin = index<2> (6,2) t_idx.tile             = index<2> (3,1) Don't move on until you are comfortable with this… the picture really helps, so use it. Tiled Matrix Multiplication Example – part 1 Let's paste here the C++ AMP matrix multiplication example, bolding the lines we are going to change (can you guess what the changes will be?) 01: void MatrixMultiplyTiled_Part1(vector<float>& vC, const vector<float>& vA, const vector<float>& vB, int M, int N, int W) 02: { 03: 04: array_view<const float,2> a(M, W, vA); 05: array_view<const float,2> b(W, N, vB); 06: array_view<writeonly<float>,2> c(M, N, vC); 07: parallel_for_each(c.grid, 08: [=](index<2> idx) restrict(direct3d) { 09: 10: int row = idx[0]; int col = idx[1]; 11: float sum = 0.0f; 12: for(int i = 0; i < W; i++) 13: sum += a(row, i) * b(i, col); 14: c[idx] = sum; 15: }); 16: } To turn this into a tiled example, first we need to decide our tile size. Let's say we want each tile to be 16*16 (which assumes that we'll have at least 256 threads to process, and that c.grid.extent.size() is divisible by 256, and moreover that c.grid.extent[0] and c.grid.extent[1] are divisible by 16). So we insert at line 03 the tile size (which must be a compile time constant). 03: static const int TS = 16; ...then we need to tile the grid to have tiles where each one has 16*16 threads, so we change line 07 to be as follows 07: parallel_for_each(c.grid.tile<TS,TS>(), ...that means that our index now has to be a tiled_index with the same characteristics as the tiled_grid, so we change line 08 08: [=](tiled_index<TS, TS> t_idx) restrict(direct3d) { ...which means, without changing our core algorithm, we need to be using the global index that the tiled_index gives us access to, so we insert line 09 as follows 09: index<2> idx = t_idx.global; ...and now this code just works and it is tiled! Closing thoughts on part 1 The process we followed just shows the mechanical transformation that can take place from the simple model to the tiled model (think of this as step 1). In fact, when we wrote the matrix multiplication example originally, the compiler was doing this mechanical transformation under the covers for us (and it has additional smarts to deal with the cases where the total number of threads scheduled cannot be divisible by the tile size). The point is that the thread scheduling is always tiled, even when you use the non-tiled model. But with this mechanical transformation, we haven't gained anything… Hint: our goal with explicitly using the tiled model is to gain even more performance. In the next post, we'll evolve this further (beyond what the compiler can automatically do for us, in this first release), so you can see the full usage of the tiled model and its benefits… Comments about this post by Daniel Moth welcome at the original blog.

    Read the article

  • Excel Issues macro may be needed

    - by user124643
    I trying to compare lists in excel. There are two lists, one list just has one column and the other has two columns, and what I am trying to do is when column A matches column C than take the value in column D and use that to replace column A. For example: Column A Column B Column C Column D Blue Blue Shirt Blue Red Pants Red Green Shoes Red Green Green Purple So the completed list should look like: Column A Column B Column C Column D Shirt Blue Shirt Shirt Red Pants Pants Green Shoes Pants Shoes Shoes Purple

    Read the article

  • Positioning divs inside a container div without the content of an upper div affecting the position o

    - by silverCORE
    Hi. I'm trying to accomplish the following layout, and I'm almost there, except for the last green div, which is going lower and lower depending on the content of the content (white) div. If I set a value for the TOP property for the green div, and then I add some more text to the content div, the green div goes lower and lower. Since the green div is child to the main container div, and the green div is relatively positioned, isn't it supposed to be placed specifically at the position indicated by the TOP value of it? If I'm incorrect...can someone please tell me how can i make it so that the green div is always displayed at the same spot within the container (gray) div, regardless of the height of the content/white div? I tried to paste the css code here but was having problems with the brower. you can see the test site source/css at http://www.rae-mx.com/test tia for the help.

    Read the article

< Previous Page | 33 34 35 36 37 38 39 40 41 42 43 44  | Next Page >