Timer used by periodic real-time threads

Hi,
periodic threads may be released periodically, for example with waitForNextPeriod(). Is this periodic release realized by a timer, like an instance of the class PeriodicTimer?
So knowing the accuracy of a periodic timer on a system may help to estimate the accuracy of wfnp()?
Thanks,
Gordon

Nope, waitForNextPeriod need have no connection to other timer functionality.
In Java RTS on Solaris, waitForNextPeriod is implemented through our Cyclic driver, whereas Timers are implemented using POSIX timers.
That said, these all use the Solaris cyclic subsystem at some level so the resolution is the same. For timers however there's potentially more room for latency as there is additional OS/libc code in the path.
David Holmes

Similar Messages

BAdI........How are they used in the real time scenario.

Im a rookie in ABAP development and i was wondering that how we use the BAdI enhancement technique in the real time scenarios. Like do we get create them or we have few already built BAdI's which we work on? Can any body please explain how this works.

Hi Ramana,
Business add-ins are enhancements to the standard version of the system.
Business Add-In is a new SAP enhancement technique based on ABAP Objects.
They can be inserted into the SAP system based on specific user requirements.
Each Business Add-In has:
at least one Business Add-In definition
a Business Add-In interface
a Business Add-In class that implements the interface
In order to enhance a program, a Business Add-In must first be defined
Subsequently two classes are automatically generated:
An interface with IF_EX_ inserted between the first and second characters of the BADI name.
An adapter class with CL_EX_ inserted between the first and second characters of the BADI name.
The Application developer creates an interface for this Add-In.
There are multiple ways of searching for BADI.
Finding BADI Using CL_EXITHANDLER=>GET_INSTANCE
Finding BADI Using SQL Trace (TCODE-ST05).
Finding BADI Using Repository Information System (TCODE- SE84).
1. Go to the Transaction, for which we want to find the BADI, take the example of Transaction VD02. Click on System->Status. Double click on the program name. Once inside the program search for CL_EXITHANDLER=>GET_INSTANCE.
Make sure the radio button In main program is checked. A list of all the programs with call to the BADIs will be listed.
The export parameter EXIT_NAME for the method GET_INSTANCE of class CL_EXITHANDLER will have the user exit assigned to it. The changing parameter INSTANCE will have the interface assigned to it. Double click on the method to enter the source code.Definition of Instance would give you the Interface name.
2. Start transaction ST05 (Performance Analysis).
Set flag field "Buffer trace"
Remark: We need to trace also the buffer calls, because BADI database tables are buffered. (Especially view V_EXT_IMP and V_EXT_ACT)
Push the button "Activate Trace". Start transaction VA02 in a new GUI session. Go back to the Performance trace session.
Push the button "Deactivate Trace".
Push the button "Display Trace".
The popup screen "Set Restrictions for Displaying Trace" appears.
Now, filter the trace on Objects:
V_EXT_IMP
V_EXT_ACT
Push button "Multiple selections" button behind field Objects
Fill: V_EXT_IMP and V_EXT_ACT
All the interface class names of view V_EXT_IMP start with IF_EX_. This is the standard SAP prefix for BADI class interfaces. The BADI name is after the IF_EX_.
So the BADI name of IF_EX_CUSTOMER_ADD_DATA is CUSTOMER_ADD_DATA
3. Go to Maintain Transaction (TCODE- SE93).
Enter the Transaction VD02 for which you want to find BADI.
Click on the Display push buttons.
Get the Package Name. (Package VS in this case)
Go to TCode: SE84->Enhancements->Business Add-inns->Definition
Enter the Package Name and Execute.
Here you get a list of all the Enhancement BADIs for the given package MB.
Have a look at http://help.sap.com/saphelp_nw04/helpdata/en/04/f3683c05ea4464e10000000a114084/content.htm
http://help.sap.com/saphelp_erp2005/helpdata/en/73/7e7941601b1d09e10000000a155106/frameset.htm
http://support.sas.com/rnd/papers/sugi30/SAP.ppt
http://www.sts.tu-harburg.de/teaching/sap_r3/ABAP4/abapindx.htm
http://members.aol.com/_ht_a/skarkada/sap/
http://www.ct-software.com/reportpool_frame.htm
http://www.saphelp.com/SAP_Technical.htm
http://www.kabai.com/abaps/q.htm
http://www.guidancetech.com/people/holland/sap/abap/
http://www.planetsap.com/download_abap_programs.htm
http://help.sap.com/saphelp_nw04/helpdata/en/c8/1975cc43b111d1896f0000e8322d00/content.htm
/people/thomas.weiss/blog/2006/04/03/how-to-define-a-new-badi-within-the-enhancement-framework--part-3-of-the-series
/people/thomas.weiss/blog/2006/04/18/how-to-implement-a-badi-and-how-to-use-a-filter--part-4-of-the-series-on-the-new-enhancement-framework
How to develop BADI
Reward if useful.
Thanks
Aneesh.

How do I sample a frequency or voice input using labview in real time?

This is my first time using labview to sample real-time! I'm trying to setup a microphone, so that when a voice is spoken to the mic I can sample the frequency, and
further customize the data in labview. The final goal is to amplify the frequency and output it to a speaker. If possible via labview. My question is do I need some type of evaluation board , microcontroller, to sample the frequencies and save the data sample to labview. Also, how would I go by doing this in real-time, or when the person is speaking to the mic the voice/frequency can be modified in labview instantenaeously. If someone can give me a step-by-step way of performing this, please let me know.
I currently use Labview 8.2 and 8.5

There are many LabVIEW shipping examples that are built to acquire sound samples from a microphone attached to a sound card. There is also an example on how to play a sound file directly to speakers, that you should definitely take a look at. These examples VIs are found in the Sound folder which is under Hardware Input and Output in the NI Example Finder. Depending on how advanced your frequency analysis will be, you might want to look into purchasing the Sound and Vibration Toolkit. For your specific application, it doesn't sound like you will need the LabVIEW Real-Time Module, you should be able to obtain very accurate results without it. Please view the article linked below for more information on this toolkit. Thanks!
Sound and Vibration Toolkit for LabVIEW
Meghan M.

Using partition in real time

Hi i am new to essbase
How we can use replicate and transperent partition option in the real time.
kindly help me in understanding this concept.

Hi,
We will use transparent partition as an interface to read the data from the source cube
A transparent partition allows users to manipulate their data that is stored in a target database as if it were part of the actual source database. The remote data is retrieved from the source database each time the users of the target database request it. Write backs to the target database also flow through back to the source database.
We can use this technique for the improved maintenance of a large data bases by splitting them into smaller databases to allow the operations on the smaller databases and stiil facilitate the users as they see in a single data base.
We can use this for the improved security maintenance.
A replicated database partition copies a portion of the source database to be stored in a target database. Users can access the target database as if it were the source. The database administrator must occasionally refresh the target database from the source database.
We can use this technique as a means of transferring data between the essbase cubes.
I will explain you a classic example.
In the current reporting cube we will maintain only two years data - previous year and current year data.
As part of year end activity, we need to move the previous year data to the History cube and the same to be deleted from the current cube.
we will create a replicated partition for the previous year b/w current and History cube.
Replicate the data from current to History cube.
drop the relicated partition and clear the prev year data in the current cube.
I hope this will suffice.

Using Views in Real time mappings?

Hello fellow OW Builders!
I have been investigating OWB 11gR2 as a solution for data warehousing. The requirement I have is to produce a real-time system, to propagate any changes in the source data as quickly as possible, to the targets. The problem I have is, I only have access to the source data via views on the database. I can create 'regular' mappings using views as a data source, as part of a batch load process. However, I cannot set up Queue Operators (required for real-time mappings), using views as the data source.
I am hoping there are some OWB gurus out there, who might be able to suggest a suitable approach, for real-time data warehousing, using views as a data source? If it helps with your creativity, it doesn't have to be an OWB solution (although I think that would be preferable). The database version for the source and targets is 10gR2, should that be of interest.
Thanks in advance for your time.
Edited by: user13130528 on 17-Aug-2010 06:49

Has this completely foxed everyone?! Even if the answer is 'no way, Jose', it would be good to know, so I can ditch OWB and concentrate on finding another solution.
Thanks!

Odd behavior on web template used to update real-time cubes

Hello all
This is my first time posting on this forum so please excuse any blunders.
I have a situation wherein 2 queries (one built on an aggregate level which is set up on a multiprovider containing a real-time cube and the other built on an aggregate level set up directly on a real-time cube) are being used to update data. For both of these queries, I'm trying to fill in fields such as user, created by, time, date etc. These fields are being filled in the custom class "ZCL_LOC_CR_LINE_ITEM" and all of the settings are correct for the aggregation level/infoproviders.
However, I'm encountering 2 problems. Firstly, for one of these queries on the web template, the fields I want filled are not getting filled in by the exit. In fact, I put hard-code break points in the exit's DERIVE method but the control is not even going in there. But for the other query, the control flows into the user-exit correctly when I hit the return key after populating all of the remaining characteristic fields on the input screen. Secondly, for the first query, the fields are not input-enabled. But I've set up both queires to be more or less similar in the sense that the fields to be populated in the user-exit are not on the query screen etc. I'm stumped and would appreciate some help from the experts out there.
Regards
Sam

Regarding yor first quesiton, if the exit is not being reached, then most likely you have not correctly defined the characteristic relationship in the planning modeler. For it all to work, go to the planning modeler for the infoprovider that you are deriving the characteristics. Ensure that your source characteristics are all contained in the aggregatin level being used by the planning query in question. Also ensure that none of the target characteristics are contained in the aggregation level.
Also, make sure that the "inactive" checkbox is not marked for the individual characteristic relationships.
Note that whether or not the query is on an multiprovider or a real-time sube, the characteristic relationships are always defined directly on the underlying real-time cube.
Regarding the second question, for a query to be input-ready:
-There must be a real-time cube in the query directly (or indirectly via mutliprovider)
-The query must start up in change mode (or be switched into change mode)
-Cell(s) must be defined as input ready either by their settings in the row or column
-Every characteristic in the aggregation level must be fully qualified (including currency,UOM, or any nav attributes used as selections)
- note that when using a mulitiprovider, it is necessary to specify the real-time infocube name in the planning cell/row/col selections
If all of the above are met, try drilling down in the query once it is presented and see if anything is unaccounted for

3D position using camera system - real time

Greetings!
I amtrying to use Labview to track an object in 3D space. I am using threehigh speed cameras which are connected via a framegrabber to my PC. Theidea is that I want to be able to throw an object, let’s say a ball, and haveLabview detect the motion and return real time stats on the object (location inxyz and the velocity vector). The object should be about the size of abird as this will be the final object tracked.
I amcurrently constrained as to where the cameras can be. They have to bepositioned in a horizontal line beside one another, but they can be turned toany angle I see fit.
Ihave some ideas of how to approach this but since this is my first visualproject I am a little unsure what the best method will be.
Oneidea I had was to have one camera centered facing strait forward and one cameraon either side if it turned 45 degrees toward the center line of vision. Thenthe idea would be to calculate the actual x-y-z position based on the geometryof the camera. However this method isless than flexable.
Anotheridea was to eliminate restrictions on the camera positions and have some sortof target system set up which would then "calibrate" the cameras foreach particular setup. I am thinkingof x and y rulers printed out and hung from the ceiling. Then, using the distances between x ruler markingscompared to y ruler markings to determine the camera angle and what the zcomponent should be. Maybe use a basketball to calibrate instead?
Solutions?Working code that takes jpegs from three saved camera files? Any help atall in 3D positioning would be much appreciated.
Thanks inadvance!!
~Chad

Chad,
Having all three cameras in a straight line is a poor choice for 3D work. Try putting one at (1,0,0), one at (0,1,0) and one at (0,0,1) or some similar distribution. Then the angle from the camera axis gives you a starting point for your 3D geometry.
Can you arrange that the object is always in the field of view of all three cameras? Do the cameras/lenses distort off-axis images?
If the object is a known size and has a simple geometric shape (sphere, cube, tetrahedron), you may be able to also use size of image to get an estimate of distance. Rotation of more complex shapes makes for a difficult calculation.
The rulers might be helpful if the object size is known. If the object size is unknown or variable, the challenge is much greater.
Lynn

Real-time database or non real-time database

I know the scheduling mechanism in Oracle database is somewhat like the Linux OS which is not real-time. Does Oracle provide real-time database which has some real-time scheduling guaranteeing each user transaction to meet with a deadline ? Thx a lot.

The Berkley DB that Oracle owns has been ported to QNX which is a real-time operating system.
http://www.oracle.com/technology/documentation/berkeley-db/db/ref/build_unix/qnx.html
Why, out of curiosity, are you looking into Oracle for a real-time system? That implies that you're running a real-time operating system on your servers, which is certainly unusual. I've heard of some ports of 9i to real-time operating systems, but that would certainly be unusual.
Justin

Time Machine backup in real time?

I'm about to get a new Mac Mini for my girlfriend and thought about getting an additional external hard drive for Time Machine backups. I have never used Time Machine and the help topics/manuals seem to indicate you can only backup every hour. Can you set it to backup as new files are being created? Sometimes she imports files from her camera and saves them downsized for the web and forgets to "save as" so the originals get deleted. Actually, it's only happened once, but if TM was backing up everything as it was being copied over there would be no problems....I hope. If this isn't an option I might not even get an external. Thanks for any information.

Can you set it to backup as new files are being created?
No. The only way to do that would be via RAID 1 (mirroring), but that's not going to help either, because as soon as you delete (or overwrite) a file its going to get deleted (or overwritten) on the mirror, too.
Seriously, though, I think you'll find Time Machine more than handles what you want, even at the hourly invocation. You say it's only happened once before anyway, and you might be surprised at how much time passes between copying the files from the camera and accidentally overwriting the original so the chances are the files will be copied anyway.
Also think of it this way, even at an hour, there's a good chance that you will have a backup of the original. Without Time Machine (or some other automatic backup system) there is zero chance. Which would you prefer?

How to check running time of program in real time?

Hello Experts,
I am currently creating a report wherein I need to check how long the program is running.
For example, If it currently runs in almost 10 minutes, I need to terminate the report or create
a message informing the user to please limit the selection of records.
Are there any FMs to do this? Thank you guys and take care!

Get runtime in two phases:
DATA: t1 type i, t2 type i, delta type i.
GET RUNTIME FIELD t1.
..... evaluation .....
GET RUNTIME FIELD t2.
delta = t2 - t1. "Microseconds!
.... check the delta and send message if necessary!
Hope this helps, R.

!!!-Need help for terminating a Java thread in real time

Hi everyone!
I use J2SDK1.4.1 on a Unix platform.
I want to terminate (or stop) a running java thread, which is dealing with time consuming tasks, in real-time (for example: the delay before the thread is terminated can't beyond one second), However, I don't know which techniques I can use to make sure the previous (or old) running java threads have been terminated?
Could you please give me any help if you can?
Any suggestion or reply will be kindly appreciated!
Thanks!

Thanks very much, jverd !
I do set a flag that the thread should periodically check !
Well, the scenario is like this:
1. the thread read line by line (using BufferedReader) string from a probably huge-size file
2. analyse each string read from the file if required (some strings may be omitted based on the user's operations), the analyzing process is a time-consuming task, and the analysing process may be terminated at any time the user want.
3. record only the strings that have been analyzed by the previous process into a recording file
The problem I meet is as follows: (Here, I suppose that it should take at least 30 seconds to finish analyse all the strings in a given huge file )
1. the user start the analysing process, and run it for only 5 seconds,then stop the analyzing.
2. the user start the analysing process again from the begining of the file(analyse the strings within the same file as previous step), and then stop the analysing process at 10 second. (it means, this time the analysing process is running for 10 seconds, still haven't finish analyse all the strings in the file).
Once I open the record file, I saw some of the strings in the recording file have been repetitively record for 2 times, and the repetitive strings are just the strings the analysing time from at 5 second to at 10 second.
And the repetitive times are depend on how many time the user start and stop the analysing process using the same file. for example, based on the above two steps, the user do the third step as follow:
3. the user start the analysing process once again, analyse the same file,too. And run it for 15 seconds
This time open the recording file, this time I saw some of the strings have been repetitively record for 3 times, and the repetitive strings are just the strings the analysing time from at 10 second to at 15 second.
So, I guess the problem is probably because the previous analysing threads haven't been terminated completely, or say they just are blocked or set as inactive etc., then when the next time start the analysing process, the old threads will be reactive,and rerun ffrom the last time they are blocked.
I hope you had catched what I mean, if you not, please ust let me know, I'll try to explain it again.
Thanks once again!

When I use Call Library Function Node in real time, is the DLL loaded once for all or load every time it is called?

When I use Call Library Function Node in real time, is the DLL loaded once for all or load every time when it is called?
I have a time critical real time application, in which I use a piece of DLL function developed by C++. It is OK? Could any senior developer assure me?
Thank you in advance.
Solved!
Go to Solution.

qing_shan61 wrote:
When I use Call Library Function Node in real time, is the DLL loaded once for all or load every time when it is called?
Once
qing_shan61 wrote:
I have a time critical real time application, in which I use a piece of DLL function developed by C++. It is OK?
OK
Be sure that all DLL calls are thread safe (do not perform calls in UI thread).
Also for real-time application you need real-time OS.
Andrey.

How to find out Tcode Used and their hit rate over a given period of time.

Hi All,
We wanted to know what are the tcodes that are used and how many times over a period of time..
Can you please suggest the ways to find this out..
I have heard of ST03N but not sure how to use this and then download the information ..
Regards,
Vidya..

Hi,
Check this
[How to get list of frequently used TCodes]

What are the limitations of using labview 8.5.1 developers suite verses a real-time module in field point applications?

What are the limitations of using labview 8.5.1 developers suite verses a real-time module in field point applications? Can an exe. be loaded onto a field point controller or does the controlling program have to reside on a PC for example?

centerbolt is correct, you can't load a .exe or even run a program on the fieldPoint controller unless you have the Real Time module. However, that does not mean you can't use your FieldPoint bank without the Real Time module.
From LabVIEW for windows you can make calls to the fieldpoint IO using the fieldpoint read/write functions.
This program runs on the PC not the FieldPoint controller. If you loose network connection to the fieldpoint, your program will loose connection to the IO. For many data logging applications this type of arrangement can work just fine. However, if this is the only type of application you are ever going to run, then you may as well not buy the Real Time controller for your fieldpoint but the network controller only.
If your application requires more reliability, and/or greater determinism than can be achieved by running a program on windows, then you should use the LabVIEW Real Time module and develop a program that can run down on the FieldPoint controller independent of windows.
Message Edited by StevenA on 07-22-2008 04:14 PM
SteveA
CLD
FPGA/RT/PDA/TP/DSC
Attachments:
fp pallet.PNG ‏6 KB

How to verify RTSJ use linux real time kernel?

Hi,
I'm complete newbie into this area and I'm trying out the RTSJ 2.1 beta Linux. I'm using this on Ubuntu with the linux real time kernel. Is there anyway to find out whether the real time kernel is being actually used or in other words is there a way to find out whether RTSJ works fine with the real time kernel on Ubuntu? I see that the programs get compiled and run irrespective of whether I use the real time kernel or the generic kernel.
Thanks,
Vidura

Hi,
I would assume, like other distributions, that you either boot the real-time kernel or you don't. uname should show you what you are running, but you'd have to ask the Ubuntu folk what you should see for the RT kernel.
To see if you are benefiting from real-time, you need to run a RTSJ app that tracks deadline misses or measures latency/jitter. Try it on the non-real-time kernel and the real-time one and see what you get. Some of the examples in the "Getting Started" guide should be usable for these purposes.
David Holmes

Timer used by periodic real-time threads

Similar Messages

Maybe you are looking for