Search Results

Search found 4291 results on 172 pages for 'cluster analysis'.

Page 147/172 | < Previous Page | 143 144 145 146 147 148 149 150 151 152 153 154  | Next Page >

• XtraGrid Suite - is there a way to add a button or hyperlink to a cell?

  - by calico-cat

  I'm working with the XtraGrid Suite made by DevExpress. I can't find any sort of functionality to do this, but I'm curious if you can add a button or hyperlink to a grid cell. Context: I've got an Events list. Each Event has a Time, Start/End, and a Category (Utility and Maintenance). There can be Start events and Stop events. Having done my analysis of the problem, I've decided that having a StartTime and EndTime for each event would not work. So if an event starts, I'd record the current time to the Event object, and set it as a 'Start' event. I'd like to add a "Stop" button/hyperlink to a cell in that row. If the user wishes to log an Ends event, the event type, etc would be copied to a new Event with the type 'Stop' and the button would disappear. I hope this makes sense. EDIT: Aaronaught's answer is actually better than what I was originally asking (a button) so I've updated the question. That way, anyone looking for putting a hyperlink in a cell can benefit from his example : )

  Read the article

• Segmentation fault on MPI, runs properly on OpenMP

  - by Bellman

  Hi, I am trying to run a program on a computer cluster. The structure of the program is the following: PROGRAM something ... CALL subroutine1(...) ... END PROGRAM SUBROUTINE subroutine1(...) ... DO i=1,n CALL subroutine2(...) ENDDO ... END SUBROUTINE SUBROUTINE subroutine2(...) ... CALL subroutine3(...) CALL subroutine4(...) ... END SUBROUTINE The idea is to parallelize the loop that calls subroutine2. Main program basically only makes the call to subroutine1 and only its arguments are declared. I use two alternatives. On the one hand, I write OpenMP clauses arround the loop. On the other hand, I add an IF conditional branch arround the call and I use MPI to share the results. In the OpenMP case, I add CALL KMP_SET_STACKSIZE(402653184) at the beginning of the main program and I can run it with 8 threads on an 8 core machine. When I run it (on the same 8 core machine) with MPI (either using 8 or 1 processors) it crashes just when makes the call to subroutine3 with a segmentation fault (signal 11) error. If I comment subroutine4, then it doesn't crash (notice that it crashed just when calling subroutine3 and it works when commenting subroutine4). I compile with mpif90 using MPICH2 libraries and the following flags: -O3 -fpscomp logicals -openmp -threads -m64 -xS. The machine has EM64T architecture and I use a Debian Linux distribution. I set ulimit -s hard before running the program. Any ideas on what is going on? Has it something to do with stack size? Thanks in advance

  Read the article

• Web-based clients vs thick/rich clients?

  - by rudolfv

  My company is a software solutions provider to a major telecommunications company. The environment is currently IBM WebSphere-based with front-end IBM Portal servers talking to a cluster of back-end WebSphere Application Servers providing EJB services. Some of the portlets use our own home-grown MVC-pattern and some are written in JSF. Recently we did a proof-of-concept rich/thick-client application that communicates directly with the EJB's on the back-end servers. It was written in NetBeans Platform and uses the WebSphere application client library to establish communication with the EJB's. The really painful bit was getting the client to use secure JAAS/SSL communications. But, after that was resolved, we've found that the rich client has a number of advantages over the web-based portal client applications we've become accustomed to: Enormous performance advantage (CORBA vs. HTTP, cut out the Portal Server middle man) Development is simplified and faster due to use of NetBeans' visual designer and Swing's generally robust architecture The debug cycle is shortened by not having to deploy your client application to a test server No mishmash of technologies as with web-based development (Struts, JSF, JQuery, HTML, JSTL etc., etc.) After enduring the pain of web-based development (even JSF) for a while now, I've come to the following conclusion: Rich clients aren't right for every situation, but when you're developing an in-house intranet-based solution, then you'd be crazy not to consider NetBeans Platform or Eclipse RCP. Any comments/experiences with rich clients vs. web clients?

  Read the article

• RotatingFileHandler throws an exception when delay parameter is set

  - by Eli Courtwright

  When I run the following code under Python 2.6 import logging from logging.handlers import RotatingFileHandler rfh = RotatingFileHandler("testing.log", delay=True) logging.getLogger().addHandler(rfh) logging.warning("Boo!") then the last line throws AttributeError: RotatingFileHandler instance has no attribute 'level'. So I add the line rfh.setLevel(logging.DEBUG) before the call to addHandler, and then the last line throws AttributeError: RotatingFileHandler instance has no attribute 'filters'. So if I manually set filters to be an empty list, then it complains about not having the attribute lock, etc. When I remove the delay=True to leave it as the default value of False as documented here, the problem completely goes away. Am I missing something? How do I properly use the delay parameter of the RotatingFileHandler class? EDIT: Upon further analysis (presented in my own answer below), this looks like a bug, but I can't find a bug report on this in the Python bug tracker, even trying different search terms, so I guess I'll report it. However, if someone can locate the actual bug report, then I can avoid submitting a duplicate reporting and wasting the time of the Python developers. I'll hold off on reporting the bug for a few hours, and if someone posts an answer that has the current bug report, then I'll accept that answer for this question.

  Read the article

• Gmail IMAP OAuth for desktop clients

  - by Sabya

  Recently Google announced that they are supporting OAUth for Gmail IMAP/SMTP. I browsed through their multiple documentations, but still I am confused about if they support OAuth for installed applications. 1. In this documentation they say: Note: Though the OAuth protocol supports the desktop/installed application use case, Google only supports OAuth for web applications. But they also have a document for OAuth for installed applications. 2. When I read the OAuth specification pointed by them, it says (in section 11.7): In many applications, the Consumer application will be under the control of potentially untrusted parties. For example, if the Consumer is a freely available desktop application, an attacker may be able to download a copy for analysis. In such cases, attackers will be able to recover the Consumer Secret used to authenticate the Consumer to the Service Provider. Also I think the disclaimer in point 1 above is about Google Data APIs, and surely IMAP/SMTP is not a part of them. I understand that for installed applications I can have a setup like: Have a small web-app at say example.com for my application. This web-app talks to Google gets the access token. The installed application talks to example.com only to get the access token. Installed application then talks to Google with the access token. I am now confused. Is this the only way?

  Read the article

• Eclipse RCP: Using different JUnit version (4.3.1) than shipped with eclipse galileo (4.5.0)

  - by Skrrytch

  Hallo, I have the following situation: We are developing an Eclipse RCP Application and want to switch from Eclipse 3.4 to Eclipse 3.5. Our JUnit-Tests are using JUnit 4.3.1 and we have a launch configuration to start our test suite. I think I don't need to go into more details here. The problem is: Running the tests with Eclipse 3.5 does not work: JUnit cannot find any annotations in the test classes (neither (at)Test nor (at)RunWith). I patched the junit library with some logging output to check what is going on. I found out that this problem is a classloading issue: The test class passed to JUnit 'lies in' a ClassLoader which is different from the one JUnit uses to load the annotation classes like 'RunWith'. This is not the case in Eclipse 3.4 in org.junit.internal.requests.ClassRequest: public Runner getRunner() { log("TestClass ClassLoader: "+this.fTestClass.getClassLoader()); log("RunWith.class ClassLoader: "+RunWith.class.getClassLoader()); ... // validating test class: searching for annotations and more } The first line prints another classloader than the second line. This is bad because JUnit cannot match the annotations in the test class with the Annotation-Class (here: RunWith.class): "RunWith" in CL1 is not equal to "RunWith" in CL2. I have a solution which points to the core problem: Replace JUnit 4.5 in Eclipse Galileo with JUnit 4.3.1 so that there is only one JUnit-Version: The Test-Run and the tests classes are both using JUnit 4.3.1 (I had to patch "org.eclipse.jdt.junit4.runtime" to accept an ealier junit version). I think I can also replace JUnit 4.3.1 in my test class with Version 4.5, but that is not an option yet. Guess: The classloaders are different because the classes 'come from' different JUnit-Bundles: the testclass with its annotations from version 4.3.1 and the test runs in version 4.5 What I want to know: Is there any other solution besides patching Eclipse (replace JUnit versions)? Any commandline argument or such? Any configuration to force Eclipse to Use JUnit 4.3.1? Any hints on the above described analysis are welcome!

  Read the article

• C# File IO with Streams - Best Memory Buffer Size

  - by AJ

  Hi, I am writing a small IO library to assist with a larger (hobby) project. A part of this library performs various functions on a file, which is read / written via the FileStream object. On each StreamReader.Read(...) pass, I fire off an event which will be used in the main app to display progress information. The processing that goes on in the loop is vaired, but is not too time consuming (it could just be a simple file copy, for example, or may involve encryption...). My main question is: What is the best memory buffer size to use? Thinking about physical disk layouts, I could pick 2k, which would cover a CD sector size and is a nice multiple of a 512 byte hard disk sector. Higher up the abstraction tree, you could go for a larger buffer which could read an entire FAT cluster at a time. I realise with today's PC's, I could go for a more memory hungry option (a couple of MiB, for example), but then I increase the time between UI updates and the user perceives a less responsive app. As an aside, I'm eventually hoping to provide a similar interface to files hosted on FTP / HTTP servers (over a local network / fastish DSL). What would be the best memory buffer size for those (again, a "best-case" tradeoff between perceived responsiveness vs. performance). Thanks in advance for any ideas, Adam

  Read the article

• Web service SSL handshake fails in production environment unless SSL debugging enabled

  - by JST

  Scenario: calling a client web service over SSL (https) with mutual SSL authentication. Different service endpoint URLs and certs (both keystore and truststore) for test vs. production environments. Both test and production environments run tomcat / JBoss clustered. Production environment has load balancing / BigIP, runs Blade and non-Blade machines. Truststore is set (using -Djavax.net.ssl.trustStore=value) at startup. Keystore is set using System.setProperty("javax.net.ssl.keyStore", "value") in Java code. Web service call made using Axis2. All works fine in test environment, but when we moved to production environment (6 servers), it appears certs are not being forwarded for the handshake. Here's what we've done: in test environment, handshake using test versions of certs has been working all along, with no ssl debugging enabled confirmed in test environment that handshake with client production endpoint succeeds (production certs, both ours and theirs, are fine) -- this was done using -Djavax.net.debug=handshake,ssl confirmed that the error condition occurs on all 6 production servers took one server out of the cluster, turned on ssl debugging for just that one (with a restart), hit it directly, handshake works! switched to a different server without the debugging turned on, handshake error condition occurs turned debugging on on that second server (with a restart), hit it directly, handshake works! From the evidence, it seems like somehow the debugging being enabled causes the certificates to be properly retrieved/conveyed, although that makes no sense! I wonder whether somehow the enabled debugging makes the system pay attention to the System.setProperty call, and ignore it otherwise. However, in local and test environments, handshake worked without debugging enabled. Do I maybe need to be setting keystore on server startup like I'm setting truststore? Have been avoiding that because the keystore will differ for each of our test environments (16 of them).

  Read the article

• How to avoid XCode framework weak-linking problems?

  - by Frank R.

  Hi, I'm building an application that takes advantage of Mac OS X 10.6-only technologies, but without giving up backwards compatibility to 10.5 Leopard. The way I do this is by setting the 10.6 SDK as the base SDK, weak-linking all frameworks and setting the deployment target to 10.5 as described in: http://developer.apple.com/mac/library/DOCUMENTATION/MacOSX/Conceptual/BPFrameworks/Concepts/WeakLinking.html This works fine; before making a call that is Snow Leopard-only I need to check that the selector or indeed the class actually exist. Or I can just check the OS version before making the call. The problem is that this is incredibly fragile. If I make a single call that is 10.6 only I blow Leopard-compatibility. So using even the normal code code completion feature can be dangerous. My question: is there any way of checking which calls are not defined on 10.5 before doing a release build? Some kind of static analysis, or even just a trick (a target set the other SDK?) would do. I obviously should test on a Leopard machine before releasing anything, but even so I can't possibly go through all paths of the program before every release. Any advice would be appreciated. Best regards, Frank

  Read the article

• Check for valid IMEI

  - by Tim

  Hi, does somebody knows how to check for a valid IMEI? I have found a function to check on this page: http://www.dotnetfunda.com/articles/article597-imeivalidator-in-vbnet-.aspx But it returns false for valid IMEI's (f.e. 352972024585360). I can validate them online on this page: http://www.numberingplans.com/?page=analysis&sub=imeinr What is the correct way(in VB.Net) to check if a given IMEI is valid? Regards, Tim PS: This function from above page must be incorrect in some way: Public Shared Function isImeiValid(ByVal IMEI As String) As Boolean Dim cnt As Integer = 0 Dim nw As String = String.Empty Try For Each c As Char In IMEI cnt += 1 If cnt Mod 2 <> 0 Then nw += c Else Dim d As Integer = Integer.Parse(c) * 2 ' Every Second Digit has to be Doubled nw += d.ToString() ' Genegrated a new number with doubled digits End If Next Dim tot As Integer = 0 For Each ch As Char In nw.Remove(nw.Length - 1, 1) tot += Integer.Parse(ch) ' Adding all digits together Next Dim chDigit As Integer = 10 - (tot Mod 10) ' Finding the Check Digit my Finding the Remainder of the sum and subtracting it from 10 If chDigit = Integer.Parse(IMEI(IMEI.Length - 1)) Then ' Checking the Check Digit with the last digit of the Given IMEI code Return True Else Return False End If Catch ex As Exception Return False End Try End Function

  Read the article

• Dashboard for collaborative science / data processing projects

  - by rescdsk

  Hi, Continuous Integration servers like Hudson are a pretty amazing addition to software development. I work in an academic research lab, and I'd love to apply similar principles to scientific data analysis. I want a dashboard-like view of which collections of data are fine, which ones are failing their tests (simple shell scripts, mostly), and so on. A lot like the Chromium dashboard (WARNING: page takes a long time to load). It takes work from at least 4 people, and maybe 10 or 12 hours of computer time, to bring our data (from behavioral studies) from its raw form to its final, easily-analyzed form. I've tried Hudson and buildbot, but neither is really appropriate to our workflow. We just want to run a bunch of tests on maybe fifty independent collections of subject data, and display the results nicely. SO! Does anyone have a recommendation of a way to generate this kind of report easily? Or, can you think of a good way to shoehorn this kind of workflow into a continuous integration server? Or, can you recommend a unit testing dashboard that could deal with tests that are little shell scripts rather than little functions? Thank you!

  Read the article

• sharing build artifacts between jobs in hudson

  - by programming panda

  Hi I'm trying to set up our build process in hudson. Job 1 will be a super fast (hopefully) continuous integration build job that will be built frequently. Job 2, will be responsible for running a comprehensive test suite, at a regular interval or triggered manually. Job 3 will be responsible for running analysis tools across the codebase (much like Job 2). I tried using the "Advanced Projects Options use custom workspace" feature so that code compiled in Job 1 can be used in Job 2 and 3. However, it seems that all build artifacts remain inside that Job 1 workspace. I'm I doing this right? Is there a better way of doing this? I guess I'm looking for something similar to a build pipeline setup...so that things can be shared and the appropriate jobs can be executed in stages. (I also considered using 'batch tasks'...but it seems like those can't be scheduled? only triggered manually?) Any suggestions are welcomed. Thanks!

  Read the article

• Useful training courses that aren't specific to a single technology

  - by Dave Turvey

  I have possibly the best problem in the world. I have about £1600 left in a training budget and I need to find something to spend it on. I can spend it on anything that could be considered training. Books, courses, conferences, etc. I would like to find a course that would benifit a software developer but is not about learning a specific programming technology. I don't really want to spend it on a technical training course. These topics are usually best learned with a good book and some trial and error. I have also already been on a general business/management training course and a PRINCE2 project management course. I am currently working on a project on my own so am responsible for communicating with the client, requirements gathering, project management, etc., as well as the coding. What training have you found useful outside the usual technical stuff? Has anyone done any business analysis courses? What were they like? Are there any courses on some of the practicalities of working with software, e.g. automated test and deployment strategies, handling technical support? I would prefer a course in the UK but I can travel if necessary.

  Read the article

• Is there an "embedded DBMS" to support multiple writer applications (processes) on the same db files

  - by Amir Moghimi

  I need to know if there is any embedded DBMS (preferably in Java and not necessarily relational) which supports multiple writer applications (processes) on the same set of db files. BerkeleyDB supports multiple readers but just one writer. I need multiple writers and multiple readers. UPDATE: It is not a multiple connection issue. I mean I do not need multiple connections to a running DBMS application (process) to write data. I need multiple DBMS applications (processes) to commit on the same storage files. HSQLDB, H2, JavaDB (Derby) and MongoDB do not support this feature. I think that there may be some File System limitations that prohibit this. If so, is there a File System that allows multiple writers on a single file? Use Case: The use case is a high-throughput clustered system that intends to store its high-volume business log entries into a SAN storage. Storing business logs in separate files for each server does not fit because query and indexing capabilities are needed on the whole biz logs. Because "a SAN typically is its own network of storage devices that are generally not accessible through the regular network by regular devices", I want to use SAN network bandwidth for logging while cluster LAN bandwidth is being used for other server to server and client to server communications.

  Read the article

• Can I make a "TCP packet modifier" using tun/tap and raw sockets?

  - by benhoyt

  I have a Linux application that talks TCP, and to help with analysis and statistics, I'd like to modify the data in some of the TCP packets that it sends out. I'd prefer to do this without hacking the Linux TCP stack. The idea I have so far is to make a bridge which acts as a "TCP packet modifier". My idea is to connect to the application via a tun/tap device on one side of the bridge, and to the network card via raw sockets on the other side of the bridge. My concern is that when you open a raw socket it still sends packets up to Linux's TCP stack, and so I couldn't modify them and send them on even if I wanted to. Is this correct? A pseudo-C-code sketch of the bridge looks like: tap_fd = open_tap_device("/dev/net/tun"); raw_fd = open_raw_socket(); for (;;) { select(fds = [tap_fd, raw_fd]); if (FD_ISSET(tap_fd, &fds)) { read_packet(tap_fd); modify_packet_if_needed(); write_packet(raw_fd); } if (FD_ISSET(raw_fd, &fds)) { read_packet(raw_fd); modify_packet_if_needed(); write_packet(tap_fd); } } Does this look possible, or are there other better ways of achieving the same thing? (TCP packet bridging and modification.)

  Read the article

• Database warehouse design: fact tables and dimension tables

  - by morpheous

  I am building a poor man's data warehouse using a RDBMS. I have identified the key 'attributes' to be recorded as: sex (true/false) demographic classification (A, B, C etc) place of birth date of birth weight (recorded daily): The fact that is being recorded My requirements are to be able to run 'OLAP' queries that allow me to: 'slice and dice' 'drill up/down' the data and generally, be able to view the data from different perspectives After reading up on this topic area, the general consensus seems to be that this is best implemented using dimension tables rather than normalized tables. Assuming that this assertion is true (i.e. the solution is best implemented using fact and dimension tables), I would like to seek some help in the design of these tables. 'Natural' (or obvious) dimensions are: Date dimension Geographical location Which have hierarchical attributes. However, I am struggling with how to model the following fields: sex (true/false) demographic classification (A, B, C etc) The reason I am struggling with these fields is that: They have no obvious hierarchical attributes which will aid aggregation (AFAIA) - which suggest they should be in a fact table They are mostly static or very rarely change - which suggests they should be in a dimension table. Maybe the heuristic I am using above is too crude? I will give some examples on the type of analysis I would like to carryout on the data warehouse - hopefully that will clarify things further. I would like to aggregate and analyze the data by sex and demographic classification - e.g. answer questions like: How does male and female weights compare across different demographic classifications? Which demographic classification (male AND female), show the most increase in weight this quarter. etc. Can anyone clarify whether sex and demographic classification are part of the fact table, or whether they are (as I suspect) dimension tables.? Also assuming they are dimension tables, could someone elaborate on the table structures (i.e. the fields)? The 'obvious' schema: CREATE TABLE sex_type (is_male int); CREATE TABLE demographic_category (id int, name varchar(4)); may not be the correct one.

  Read the article

• Starting out NLP - Python + large data set

  - by pencilNero

  Hi, I've been wanting to learn python and do some NLP, so have finally gotten round to starting. Downloaded the english wikipedia mirror for a nice chunky dataset to start on, and have been playing around a bit, at this stage just getting some of it into a sqlite db (havent worked with dbs in the past unfort). But I'm guessing sqlite is not the way to go for a full blown nlp project(/experiment :) - what would be the sort of things I should look at ? HBase (.. and hadoop) seem interesting, i guess i could run then im java, prototype in python and maybe migrate the really slow bits to java... alternatively just run Mysql.. but the dataset is 12gb, i wonder if that will be a problem? Also looked at lucene, but not sure how (other than breaking the wiki articles into chunks) i'd get that to work.. What comes to mind for a really flexible NLP platform (i dont really know at this stage WHAT i want to do.. just want to learn large scale lang analysis tbh) ? Many thanks.

  Read the article

• Are PyArg_ParseTuple() "s" format specifiers useful in Python 3.x C API?

  - by Craig McQueen

  I'm trying to write a Python C extension that processes byte strings, and I have something basically working for Python 2.x and Python 3.x. For the Python 2.x code, near the start of my function, I currently have a line: if (!PyArg_ParseTuple(args, "s#:in_bytes", &src_ptr, &src_len)) ... I notice that the s# format specifier accepts both Unicode strings and byte strings. I really just want it to accept byte strings and reject Unicode. For Python 2.x, this might be "good enough"--the standard hashlib seems to do the same, accepting Unicode as well as byte strings. However, Python 3.x is meant to clean up the Unicode/byte string mess and not let the two be interchangeable. So, I'm surprised to find that in Python 3.x, the s format specifiers for PyArg_ParseTuple() still seem to accept Unicode and provide a "default encoded string version" of the Unicode. This seems to go against the principles of Python 3.x, making the s format specifiers unusable in practice. Is my analysis correct, or am I missing something? Looking at the implementation for hashlib for Python 3.x (e.g. see md5module.c, function MD5_update() and its use of GET_BUFFER_VIEW_OR_ERROUT() macro) I see that it avoids the s format specifiers, and just takes a generic object (O specifier) and then does various explicit type checks using the GET_BUFFER_VIEW_OR_ERROUT() macro. Is this what we have to do?

  Read the article

• Boost Mersenne Twister: how to seed with more than one value?

  - by Eamon Nerbonne

  I'm using the boost mt19937 implementation for a simulation. The simulation needs to be reproducible, and that means storing and potentially reusing the RNG seeds later. I'm using the windows crypto api to generate the seed values because I need an external source for the seeds and not because of any particular guarantees of randomness. The output of any simulation run will have a note including the RNG seed - so the seed needs to be reasonably short. On the other hand, as part of the analysis of the simulation, I'll be comparing several runs - but to be sure that these runs are actually different, I'll need to use different seeds - so the seed needs to be long enough to avoid accidental collisions. I've determined that 64-bits of seeding should suffice; the chance of a collision will reach 50% after about 2^32 runs - that probability is low enough that the average error caused by it is negligible to me. Using just 32-bits of seed is tricky; the chance of a collision reaches 50% already after 2^16 runs; and that's a little too likely for my tastes. Unfortunately, the boost implementation either seeds with a full state vector - which is far, far too long - or a single 32-bit unsigned long - which isn't ideal. How can I seed the generator with more than 32-bits but less than a full state vector? I tried just padding the vector or repeating the seeds to fill the state vector, but even a cursory glance at the results shows that that generates poor results.

  Read the article

• Pros & Cons of Google App Engine

  - by Rishi

  Pros & Cons of Google App Engine [An Updated List 21st Aug 09] Help me Compile a List of all the Advantages & Disadvantages of Building an Application on the Google App Engine Pros: 1) No Need to buy Servers or Server Space (no maintenance). 2) Makes solving the problem of scaling much easier. Cons: 1) Locked into Google App Engine ?? 2)Developers have read-only access to the filesystem on App Engine. 3)App Engine can only execute code called from an HTTP request (except for scheduled background tasks). 4)Users may upload arbitrary Python modules, but only if they are pure-Python; C and Pyrex modules are not supported. 5)App Engine limits the maximum rows returned from an entity get to 1000 rows per Datastore call. 6)Java applications may only use a subset (The JRE Class White List) of the classes from the JRE standard edition. 7)Java applications cannot create new threads. Known Issues!! http://code.google.com/p/googleappengine/issues/list Hard limits Apps per developer - 10 Time per request - 30 sec Files per app - 3,000 HTTP response size - 10 MB Datastore item size - 1 MB Application code size - 150 MB Pro or Con? App Engine's infrastructure removes many of the system administration and development challenges of building applications to scale to millions of hits. Google handles deploying code to a cluster, monitoring, failover, and launching application instances as necessary. While other services let users install and configure nearly any *NIX compatible software, App Engine requires developers to use Python or Java as the programming language and a limited set of APIs. Current APIs allow storing and retrieving data from a BigTable non-relational database; making HTTP requests; sending e-mail; manipulating images; and caching. Most existing Web applications can't run on App Engine without modification, because they require a relational database.

  Read the article

• Weblogic 10.3.0 : Loosing a stateless session bean in the bean pool

  - by KlasE

  Hi, We have a strange situation where we loose a Stateless SessionBean in a Bean Pool in Weblogic 10.3.0 Since we only have one bean in the pool, this effectively hangs all incoming calls. We do not want more than one instance in the pool because of application restrictions. In the Weblogic admin console, we can see that there are 1 instance in the bean pool, 0 beans in use and 1 waiting incoming request. The question is, what can have caused the system to not send the request to the one obviously free bean instance? This happens after several hours and over 100000 incoming requests, and the same scenario worked fine in the old weblogic 8 environment. We get the following stacktrace: "[ACTIVE] ExecuteThread: '5' for queue: 'weblogic.kernel.Default (self-tuning)'" waiting for lock java.util.concurrent.locks.AbstractQueuedSynchronizer$ConditionObject@b0d484 TIMED_WAITING sun.misc.Unsafe.park(Native Method) java.util.concurrent.locks.LockSupport.parkNanos(LockSupport.java:198) java.util.concurrent.locks.AbstractQueuedSynchronizer$ConditionObject.await(AbstractQueuedSynchronizer.java:2054) weblogic.ejb.container.pool.StatelessSessionPool.waitForBean(StatelessSessionPool.java:269) weblogic.ejb.container.pool.StatelessSessionPool.getBean(StatelessSessionPool.java:111) weblogic.ejb.container.manager.StatelessManager.preInvoke(StatelessManager.java:148) weblogic.ejb.container.internal.BaseRemoteObject.preInvoke(BaseRemoteObject.java:227) weblogic.ejb.container.internal.StatelessRemoteObject.preInvoke(StatelessRemoteObject.java:52) com.mycompany.beans.MessageLogFacace_n73y0z_EOImpl.isMyStuffValid(MessageLogFacace_n73y0z_EOImpl.java:261) com.mycompany.beans.MessageLogFacace_n73y0z_EOImpl_WLSkel.invoke(Unknown Source) weblogic.rmi.internal.BasicServerRef.invoke(BasicServerRef.java:589) weblogic.rmi.cluster.ClusterableServerRef.invoke(ClusterableServerRef.java:230) weblogic.rmi.internal.BasicServerRef$1.run(BasicServerRef.java:477) weblogic.security.acl.internal.AuthenticatedSubject.doAs(AuthenticatedSubject.java:363) weblogic.security.service.SecurityManager.runAs(Unknown Source) weblogic.rmi.internal.BasicServerRef.handleRequest(BasicServerRef.java:473) weblogic.rmi.internal.wls.WLSExecuteRequest.run(WLSExecuteRequest.java:118) weblogic.work.ExecuteThread.execute(ExecuteThread.java:201) weblogic.work.ExecuteThread.run(ExecuteThread.java:173) Any help would be very welcome. Regards Klas

  Read the article

• Oracle T4CPreparedStatement memory leaks?

  - by Jay

  A little background on the application that I am gonna talk about in the next few lines: XYZ is a data masking workbench eclipse RCP application: You give it a source table column, and a target table column, it would apply a trasformation (encryption/shuffling/etc) and copy the row data from source table to target table. Now, when I mask n tables at a time, n threads are launched by this app. Here is the issue: I have run into a production issue on first roll out of the above said app. Unfortunately, I don't have any logs to get to the root. However, I tried to run this app in test region and do a stress test. When I collected .hprof files and ran 'em through an analyzer (yourKit), I noticed that objects of oracle.jdbc.driver.T4CPreparedStatement was retaining heap. The analysis also tells me that one of my classes is holding a reference to this preparedstatement object and thereby, n threads have n such objects. T4CPreparedStatement seemed to have character arrays: lastBoundChars and bindChars each of size char[300000]. So, I researched a bit (google!), obtained ojdbc6.jar and tried decompiling T4CPreparedStatement. I see that T4CPreparedStatement extends OraclePreparedStatement, which dynamically manages array size of lastBoundChars and bindChars. So, my questions here are: Have you ever run into an issue like this? Do you know the significance of lastBoundChars / bindChars? I am new to profiling, so do you think I am not doing it correct? (I also ran the hprofs through MAT - and this was the main identified issue - so, I don't really think I could be wrong?) I have found something similar on the web here: http://forums.oracle.com/forums/thread.jspa?messageID=2860681 Appreciate your suggestions / advice.

  Read the article

• Database warehoue design: fact tables and dimension tables

  - by morpheous

  I am building a poor man's data warehouse using a RDBMS. I have identified the key 'attributes' to be recorded as: sex (true/false) demographic classification (A, B, C etc) place of birth date of birth weight (recorded daily): The fact that is being recorded My requirements are to be able to run 'OLAP' queries that allow me to: 'slice and dice' 'drill up/down' the data and generally, be able to view the data from different perspectives After reading up on this topic area, the general consensus seems to be that this is best implemented using dimension tables rather than normalized tables. Assuming that this assertion is true (i.e. the solution is best implemented using fact and dimension tables), I would like to see some help in the design of these tables. 'Natural' (or obvious) dimensions are: Date dimension Geographical location Which have hierarchical attributes. However, I am struggling with how to model the following fields: sex (true/false) demographic classification (A, B, C etc) The reason I am struggling with these fields is that: They have no obvious hierarchical attributes which will aid aggregation (AFAIA) - which suggest they should be in a fact table They are mostly static or very rarely change - which suggests they should be in a dimension table. Maybe the heuristic I am using above is too crude? I will give some examples on the type of analysis I would like to carryout on the data warehouse - hopefully that will clarify things further. I would like to aggregate and analyze the data by sex and demographic classification - e.g. answer questions like: How does male and female weights compare across different demographic classifications? Which demographic classification (male AND female), show the most increase in weight this quarter. etc. Can anyone clarify whether sex and demographic classification are part of the fact table, or whether they are (as I suspect) dimension tables.? Also assuming they are dimension tables, could someone elaborate on the table structures (i.e. the fields)? The 'obvious' schema: CREATE TABLE sex_type (is_male int); CREATE TABLE demographic_category (id int, name varchar(4)); may not be the correct one.

  Read the article

• Keyboard hook return different symbols from card reader depends whther my app in focus or not

  - by user363868

  I code WinForm application where one of the input is magnetic stripe card reader (CR). I am using code George Mamaladze's article Processing Global Mouse and Keyboard Hooks in C# on codeproject.com to listen keyboard (USB card reader acts same way as keyboard) and I have weird situation. One card reader CR1 (Unitech MS240-2UG) produces keystroke which I intercept on KeyPress event analyze that I intercept certain patter like %ABCD-6EFJHI? and trigger some logic. Analysis required because user can type something else into application or in another application meanwhile my app is open When I use another card reader CR2 (IdTech IDBM-334133) keystroke intercepted by hook started from number 5 instead of % (It is actually same key on keyboard). Since it is starting sentinel it is very important for me to have ability recognize input from card reader. Moreover if my app running in background and I have focus on Notepad when I swipe card string %ABCD-6EFJHI? appears in Notepad and same way, with proper starting character) intercepted by keyboard hook. If swiped when focus on Form it is 5ABCD-6EFJHI? User who tried app with another card reader has same result as me with CR2. Only CR1 works for me as expected I was looking into Device manager of Windows and both devices use same HID driver supplied by MS. I checked devices though respective software from CR makers and starting and ending sentinels set to % and ? respective on both. I would appreciate and ideas and thoughts as I hit the wall myself Thank you

  Read the article

• Access SSAS cube from across domains without direct database connection

  - by SuperKing

  Hello, I'm working with SQL Server Analysis Services for the first time and have the dilemma of working on a project in which users must be able to access SSAS Cubes (via a custom web dashboard) that live across different servers and domains, but without having access to the other server's SSAS database connection strings. So Organization A and Organization B will have their own cubes on their own servers, but Organization A users must be able to view Organization B's cubes, and Organization B users must be able to view Organization A's cubes, but neither organization should have access to the connection string. I've read about allowing HTTP access to the SSAS server and cube from the link below, but that requires setting up users for authentication or allowing anonymous access to one organization's server for users of another organization, and I'm not sure this would be acceptable for this situation, or if this is the preferred way to do this. Is performance acceptable here? http://technet.microsoft.com/en-us/library/cc917711.aspx I also wonder if perhaps it makes sense to run a nightly/weekly process that accesses the other organization's SSAS database via a web service or something, and pull that data into a database on the organization's server, and then rebuild the cube. Then that cube would be queried without having to go and connect to the other organization server when viewing the cube. Has anyone else attempted to accomplish something similar? Is HTTP access the standard way to go for this? Or any other possible options? Thanks, and please let me know if you need more info, still unclear on how some of this works.

  Read the article

< Previous Page | 143 144 145 146 147 148 149 150 151 152 153 154  | Next Page >