with a new project we encountered some strange behaviour on our ColdFusion application.
Whenever a single request is initiated from the browser, the code of the cfml-templates is
executed multiple times. Upon viewing the corresponding log-files we found out, that indeed
for some reason the same request fires the evaluation in our application multiple times. One request
generates several entries. This is especially the case for long-running requests, such as database imports.
The ColdFusion application implements a REST-service, but even on manually requesting a resource,
such as a certain cfml page, on the same application - the code gets executed an unknown amount of times(variable initializations, database write-operations etc. take place), and if the request runs too long (cap at around ~4-6 seconds) there is no response to the browser.
About the infrastructure:
The application is Coldfusion18 with Tomcat Standard Edition
The webserver is an Apache (2.4.6).
Everything runs on a Linux machine with Cent OS 7.7
The corresponding Java version is 11.0.4
Our best guess is that there might be some misscommunication between the coldfusion connector with
the apache webserver. We actually searched for some configuration parameters that could cause the
problem, without success. Upon an installation on a windows machine we did not encounter that error.
Anyone got any idea?
we just found our answer in the following post:
Link to Solution
Related
We have a test website that uses Persits ASPPDF to build a PDF using the ImportFromUrl method. It works fine on our test domain, but when I use the same code on another domain (and crucially perhaps, a sub-domain) I get the "MSXML2::ServerXMLHTTP Error: The request has timed out." error.
This leads me to think its related to the problem outlined in
https://support.persits.com/show.asp?code=PS080709171
"the calling Active Server Page (ASP) should not send requests to an ASP in the same virtual directory or to another virtual directory in the same pool or process. This can result in poor performance due to thread starvation."
So perhaps the config of the two servers hosting the two sites (test and live) are different - and if so what would that be? - Or you can't run this method on a sub-domain? Any guidance out there please?
I've had the same issue for weeks and finally found out what the problem was. In my case, it was because I had set to True the options that allow the debug of classic ASP code, without which I could not debug using visual studio. Setting those options back to False fixed the issue.
Our users are restless. They keep complaining about woolly, unmeasurable stuff, particularly slowness, without giving specifics, which of course makes it very difficult to track down.
Nonetheless, it is quite possible that they are right, that there are server calls that are taking way too long to come back. So I want to put some kind of sniffer on the web site (we're using ASP.NET MVC 4 on IIS7) that will log any call that takes more than n seconds to turn around, or that returns more than x megabytes of data, along with all request parameters, the response size, and maybe a certain amount of response data.
I haven't a clue how to do this, though. Any suggestions?
here is my take on this:
FRT
While you can use failed request tracing to log slow requests, in my experience is more useful for finding out why a request fails before it hits your application, rather than why its running slowly. 9/10 times its going to simply show you that the slowdown is in your code somewhere.
Log Parser
Yes you can download and analyze iis logs. I use Log Parser Lizard to do the analysis - its a great gui over log parser. Here's a sample of how you might query slow requests over 1000ms:
SELECT
To_String(To_timestamp(date, time), 'dd/MM/yyyy hh:mm:ss') As Time,
cs-uri-stem, cs-uri-query, cs-method, time-taken, cs-bytes, sc-status
FROM
'C:\inetpub\logs\LogFiles\W3SVC1\u_ex140721.log'
WHERE
time-taken > 1000
ORDER BY time-taken desc
New Relic
My recommendation - go easy on yourself and sign up for a free trial. No I don't work for them, but I've used their APM product a lot. Install the agent on the server - set it up. In 10 mins you will be amazed at the data you see about the site. Trust me.
Its designed to work in production environments and gives you amazing depth of info on what's running slow, down to the database query and stack traces. Its pure awesome. Once its setup wait for the next user complaint, log in and look at traces for the time frame.
When your pro trial ends, you can still get valuable data on the free tier, but it will only keep last 24 hours. We purchased licenses -expensive yes, but worth every cent. Why? Time taken to identify root causes was reduced by an order of magnitude, we can get proactive by looking at what is number 2, 3 and 4 on the slow requests list and working those before they become big problems, and finally the alerting makes us much more responsive when things were going wrong.
Code it
You could roll you own. This blog uses Mvc ActionFilters to do the logging. You could also use an HttpModule similar to this post. The nice thing about this approach is you can compile and implement the module separately from your application, and then just drop in the dll and update web.config to wire up the module. I would be wary of these approaches for a very busy site. Also, getting the right level of detail to fully identify the root is challenging.
View Requests
As touched on by Appleman1234, IIS has a little known feature to look at requests currently executing. Its handy for the 'hey its running slow right now' situation. You can use appcmd.exe or the IIS gui to do it. You will need to install the 'Request Monitor' IIS feature for this to work. This approach is ok for rudimentary narrowing of the problem, but does not show you whats running slowly in your controller.
There are various ways you can do this:
Failed Requests Tracing(FRT) – formerly known as Failed Request Event Buffering (FREB) with custom failure condition of takes over a certain time to load / run
Logging request information with IIS logging functionality and then using a tool like LogParserStudio
Using tools like Fiddler or IISMonitor on the IIS server to capture request information
For FRT the official documentation is available here and information how to capture dumps for long running process is avaliable here
For logging request information in IIS information about log file analysis is located here
For information on configuring Fiddler to capture IIS requests find information here
A summary of the steps in the linked resources is provided below.
For FRT
From IIS Manager for a given site,In the Actions pane, under Configure, click Failed Request Tracing and enter desired values in dialog box to enable Failed Request Tracing.
From IIS Manager for a given site, under IIS click Failed Request Tracing Rules, in order to define rules of failure for a given request. In the Actions pane, click Add and follow the wizard.
The logs will go in the directory you specify and are viewable in a web broswer.
For IIS logging
Logging is enabled by default on IIS
From IIS Manager for a given site,under IIS click Logging, and in the Actions Pane, click Enable to enable logging if it isn't already.
From IIS Manager for a given site,under IIS click Logging, and then configure as desired and click apply.
Install LogParser, .Net 4.x and LogParserStudio (if you need additional steps see here
Open LogParserStudio and add logs to it, you then can use SQL queries to get information from the log files.
For Fiddler
You need to change the user that IIS runs as to a user that can launch applications, like Fiddler (instead of Network Service), and then launch Fiddler with that user.
Also see Monitor Activity on a Web Server (IIS 7) for further information.
I am using a java raw HTTP client to connect to Shopify API (specifically, using Play Framework with the non-defualt sync driver which is actually the JDK's default driver).
My application usually manages to connect successfully and convert the temporary access token into a permanent one by calling the /admin/oauth/access_token endpoint.
However, sometimes I get this error result from the API:
Generic Error(400)
{"error":"invalid_request"}
I haven't been able to reproduce the issue with my test stores - I've tried installing a fresh store, reinstalling existing stores after uninstalling, I'm not sure why this call sometimes fail and how to debug it. The API call still continues to succeed for some stores using our application.
Some things that I am doing:
Even if the URL of the store is on a custom domain, I'm always using the https://foo.myshopfiy.com/admin/oauth/access_token URL and not the URL of the custom domain, to prevent a redirect.
I am always using an https URL and never an http one, again to prevent a redirect (we noticed a few issues with redirect with the Java HTTP client, so we aim to have zero redirects)
A thread I found about this error suggest possible problems with our SSL certificates, however I don't think this is my problem because some requests work for us, and the result of running openssl on our machine does't show any issues.
How should I proceed? Open a support ticket with Shopify?
FYI, I see that this specific problem only started yesterday on Feb 19 2013, so it might be a temporary issue.
FYI, the problem was caused by reusing a temporary access code.
Our fault - Shopify could have been more clear in their error message though.
We are running a Domino 8.5.3 and the server log is constantly issuing these errors:
HTTP JVM:
!err.PersistenceServiceResourceProvider.Errorwritingtopersistedcontenttor!
We have not been able to isloate it to a particular page. Eventually, the HTTP task will crash and we need to reboot the server and recompile all the databases on the server. We are using the CKEditor to generate the HTML content. You help would be most appreciated.
We used to get this exact error a lot which appeared to be caused by inline images uploaded via the CKEditor like Paul mentioned.
I don't know why but we fixed it by changing the directory domino uses for uploads via the
xsp property xsp.persistence.dir.xspupload (formally xsp.upload.directory)
changing it to something like c:\temp rather than the windows default made the problem go away. could have been a co-incidence but may have been something in windows interfering
I haven't seen that error before but it reads like it might be something to do with asking the server to make a lot of data available to the xpages between calls to the server- effectively, session and application scope data.
I have created a web application in Apache Cocoon.This website is running properly but after every 3-4 days, it stops responding. It doesn't run until and unless, we restart the tomcat service. In the catalina.2011-05-09.log file, it shows following error:-
"May 9, 2011 3:17:34 AM org.apache.catalina.loader.WebappClassLoader clearReferencesThreads
SEVERE: The web application [/webresources] is still processing a request that has yet to finish. This is very likely to create a memory leak. You can control the time allowed for requests to finish by using the unloadDelay attribute of the standard Context implementation."
I am not been able to understand the cause of this problem. Can someone suggest me how to resolve this issue?
You are using a library that is starting one or more threads and is not properly shutting them down or releasing other resources captured by the thread. This often happens with things like Apache HTTP components (I get this error with Http Components) and anything that uses separate threads internally. What libraries are you using in your Cocoon application?
It is telling you the issue:
[...] is still processing a request that has yet to finish
You need to find out what that request is/is going to. One easy way is to have something like PsiProbe installed.
Also, it's not a bad idea to restart Tomcat every night. It can help alleviate these kinds of issues until you find the root cause.