Now that I am using it for backend processing of csv files, and the cf8 standard is limited to ten threads, I want to make sure i won't somehow overload the server...
Any suggestions?
I am making uniquely named threads, but i am worried about performance...also what if i need to stop a thread, how do i do that?
Thank You.
ColdFusion 9's Server Monitor will allow you to measure server performance such as Memory, Requests and specific Threads. Prior to ColdFusion 9 you needed to use third party utilities such as FusionReactor to monitor threads (www.fusion-reactor.com). While I have not used FusionReactor, it does have a good reputation in the CF community.
In the Administrator settings, you can change how many of your available threads are used for background processing. The setting is at the bottom of the Request Tuning page.
Log into the ColdFusion Administrator Server Monitor. Select the "Statistics" tab, and choose "Active ColdFusion Threads" under the "Request Statistics" menu. From there you can see what threads are running, and you can stop them by clicking the red "Abort Request" symbol to the left of the thread name. That will let you keep an eye on running threads and you can tune from there.
There is no real way to monitor threads, unless you have the server monitor on, and for cf8 standard that is disabled.
There's no way, I could find to list active threads, in a query or java code...
Which would be an important improvement, to have some kind of tracking mechanism.
I can't make a solution for something that is not available to me in information or statistics.
Thank You all for your effrots.
td = createObject('java', 'coldfusion.monitor.util.CFthreadDictionary');
writedump(td.getInstance().getAllActiveThreads());
Related
I inherited a coldfusion MX7 application that has a long running process, which the user kicked by accident.
By my calculations, at the current rate, the job will run for 3 days.
There doesnt seem to be a way through the administrator interface to stop a job that is running.
The table that is being filled can be easily repopulated, so I would think stopping the coldfusion service wont effect anything except the table, which isnt a problem.
Am I right? Is that safe? Is there another way?
a one-time restart of the service should be fine. for the future, you may want to add a required url param or other such safety mechanism to keep this long process from accidentally going off.
Check to see if the task already has an explicit timeout out set
Explicit Timeout
Otherwise the default page time out is used
Server Settings
For newer versions of ColdFusion 8 and above, you can kill a running page with with the Server Monitor in the section labeled "Aborting unresponsive or troublesome requests/threads"
Using server monitor.
It also may be possible to stop the processing by killing the SQL Server Task:
Is there a task manager of sorts for SQL Server 2008 and on?
I want to make a tool that runs on win32 to monitor our online game servers. The servers actually are .exe files. I need to know whether they have crashed so I can restart them. Therefore, the tool will have 2 main features:
Frequently check a list of the server programs to see whether they are running or not
Reopen the executable of any server that has crashed
Does anyone have any idea or knows an API to start with?
If you're in Win32, you can start out with C# using System.Diagnostics
using System.Diagnostics;
Then get a process list:
Process[] processlist = Process.GetProcesses();
foreach(Process theprocess in processlist){
Console.WriteLine(“Process: {0} ID: {1}”, theprocess.ProcessName, theprocess.Id);
}
And from there it's up to you what you want to do with the info.
Game servers should produce logs. You should make a service / cron job to monitor the logs. Depends on the contents of logs, your service should act respective actions, e.g. restart service, trigger alarms, etc.
I realize that this is not exactly what you asked for, but what about doing the monitoring with a fully-fledged monitoring tool such as Nagios? You would of course have to "teach" the monitoring tool about the processes that shall be monitored but you would also profit from its more advanced functions. In the case of Nagios, for example, these would comprise automatic e-mail notifications, an online dashboard of process status, notifications via SMS etc.
You should start the game servers using CreateProcess or similar in the win32 api.
You will get back a process handle in the lpProcessInformation parameter.
You can use WaitForSingleObject to WaitForMultipleObjects to wait until that handle is notified which will happen when the process terminates for any reason.
I'm putting together a website that will track user-defined events with time limits. Every user would be free to create events, and when the time limit expired, the server would need to take some action based on the outcome of the event. The specific component I'm struggling with is the time-keeping: think like eBay's auction clock -- it's set to expire at a certain time, clearly runs server-side, and takes some action when the time runs out. Searches for a "server side timer," unfortunately, just bring back results for a timer that gets the time from the server instead of the client. :(
The most obvious solution is to run a script on the server, some program that would watch all the clocks and take action when any of them expired. Tragically, I'll be using free web hosting, and sincerely doubt that I'll be able to find someone who'll let me run arbitrary stuff on their servers.
The solutions that I've looked into:
Major concept option 1: persuade each user's browser to run the necessary timers (trivial javascript), and when the timers expire, take necessary action. The problem with this approach is obvious: there could be hundreds, if not thousands, of simultaneous expiring timers (they'll tend to expire in clusters), and the worst case is that every possible user could be viewing their timer expire. That's a server overload waiting to happen at the worst possible instant.
Major concept option 2: have one really trusted browser, say, a user logged in to the website as "cron" which could run all of the timers at once. The action would all happen in that browser's javascript, and would work great, as long as that browser never crashed, that machine never failed, and that internet connection never went down.
As you can see, I feel like I'm barking up the wrong forest on this problem. Some other ideas that have presented themselves:
AJAX: I'm not seeing anything here that will do quite what I need. It's all browser-run stuff, nothing like a server-side process that could run independent of the user's browser.
PHP: Runs neatly on the server, but only in response to client requests. I'm not seeing any clean way to make PHP fork off a process and run a timer independent of the user's browser.
JS: same problems as PHP, but easier to read. ;)
Ruby: There may be some multi-threading with Ruby, but it isn't readily apparent to me. Would it be possible to have each user's browser check to see if a timer process was running for their event, and spawn a new server-side ruby process if it wasn't?
I'm wide open for ideas -- I've started playing with concepts in JS and PHP, but I'm not tied to any language, particularly. The only constraint, really, is that I won't own the server that I'm running the site on, so I can't just run a neat little local process that does what I need it to do. :(
Any thoughts? Thanks in advance,
Dan
ASP.NET has multi-threading. You can have a static variable to collect the event data, and use a thread to do whatever needed when the time comes. After you can empty the static variable so it's ready for future use.
http://leedale.wordpress.com/2007/07/22/multithreading-with-aspnet-20/
You might want to take a look at the Quartz scheduler for Java which also has a .NET version. With a friendly open source license (Apache 2.0) this is probably a very good starting point.
If you can control cron jobs, which at least I could on HostPapa's shared hosting, you could run a php file every second which checks the timers and takes action based on them.
I would suggest AJAX anyway, what we did on a game server was emulation of "server connects to client" via AJAX request to server without any time-out (asynchronous connection). Basically you create one extra connection for each client that hangs on the server and waits for the server to take self-invoked action. After the action is done you start a new hanging connection immediately so you have one hanging all the time (so the server can talk to your client any time it wants). You can send javascript code from the server that will decide what will happen next. You can check clients to have these hanging connections on the server side to count as valid and of course run your timers on the server.
I am writing a scheduled task which I would like to run frequently.
The problem is that I do not want this task to be run if the server is experiencing a high traffic load.
Is there any way other then getting the free/total/max memory from java to try and figure out whether this task should continue?
GetMetricData() is going to give you a very good indication of how busy your server is, i.e. how many requests are running and how many are queued as well as other info.
It's the same info that you get from running cfstat from the command line (you'll find that under {cfroot}\bin\cfstat.exe).
However, knowing how busy you are at the very moment might not be very useful to you if you just call that function once. It might be better for you to log performance data to file or to a database table using Windows perfmon. You can then get the average number of running/queued requests over the past 5 minutes (or whatever) and make your decision on whether to run your task.
There's an easy way to retrieve the memory usage information.
http://misterdai.wordpress.com/2009/11/25/retrieving-coldfusion-memory-usage/
For CPU load I think you can get it from getMetricData() but there are other methods too, but since this is my first stackoverflow post I'm only allowed one link :P But it's on my blog so just do a CPU search when you look at the link above.
You might find it useful to dig into getMetricData() for the performance monitoring stats. It's a good way of telling how busy your server is by the number of running and queued requests.
Hope this helps,
Dave (aka Mister Dai)
Use the ColdFusion AdminApi. Call http://servername/CFIDE/adminapi/servermonitor.cfc in your browser to get the cfcdocs of the component. If gives you many methods to get the health of you CF server instance.
I am developing a Windows Phone app where users can update a list. Each update, delete, add etc need to be stored in a database that sits behind a web service. As well as ensuring all the operations made on the phone end up in the cloud, I need to make sure the app is really responsive and the user doesn’t feel any lag time whatsoever.
What’s the best design to use here? Each check box change, each text box edit fires a new thread to contact the web service? Locally store a list of things that need to be updated then send to the server in batch every so often (what about the back button)? Am I missing another even easier implementation?
Thanks in advance,
Data updates to your web service are going to take some time to execute, so in terms of providing the very best responsiveness to the user your best approach would be to fire these off on a background thread.
If updates not taking place (until your app resumes) due to a back press is a concern for your app then you can increase the frequency of sending these updates off.
Storing data locally would be a good idea following each change to make sure nothing is lost since you don't know if your app will get interrupted such as by a phone call.
You are able to intercept the back button which would allow you to handle notifying the user of pending updates being processed or requesting confirmation to defer transmission (say in the case of poor performing network location). Perhaps a visual queue in your UI would be helpful to indicate pending requests in your storage queue.
You may want to give some thought to the overall frequency of data updates in a typical usage scenario for your application and how intensely this would utilise the network connection. Depending on this you may want to balance frequency of updates with potential power consumption.
This may guide you on whether to fire updates off of field level changes, a timer when the queue isn't empty, and/or manipulating a different row of data among other possibilities.
General efficiency guidance with mobile network communications is to have larger and less frequent transmissions rather than a "chatty" or frequent transmissions pattern, however this is up to you to decide what is most applicable for your application.
You might want to look into something similar to REST or SOAP.
Each update, delete, add would send a request to the web service. After the request is fulfilled, the web service sends a message back to the Phone application.
Since you want to keep this simple on the Phone application, you would send a URL to the web service, and the web service would respond with a simple message you can easily parse.
Something like this:
http://webservice?action=update&id=10345&data=...
With a reply of:
Update 10345 successful
The id number is just an incrementing sequence to identify the request / response pair.
There is the Microsoft Sync Framework recently released and discussed some weeks back on DotNetRocks. I must admit I didnt consider this till I read your comment.
I've not looked into the sync framework's dependencies and thus capability for running on the wp7 platform as yet, but it's probably worth checking out.
Here's a link to the framework.
And a link to Carl and Richard's show with Lev Novik, an architect on the project if you're interested in some background info. It was quite an interesting show.