RE: TC 4.1.12 on Linux - session swapping
I took a look at the code. UGLY. All of the code is in the JSP and there are no class variables. There are lots of page scope beans. Page scope is not something that I am used to using. I usually use request. Could this be a problem where the next request is hitting the page before it has died in a high-volume scenario? --- Altankov Peter [EMAIL PROTECTED] wrote: This has the taste of a thread safety issue. Do you guys happen to run the query against the same servlet? If yes, do you happen to use variables, defined in the servlet class scope in order to extract objects from session? BR -Original Message- From: Norris Shelton [mailto:[EMAIL PROTECTED] Sent: 07 ßíóàðè 2004 ã. 16:17 To: 'Tomcat Users List' Subject: TC 4.1.12 on Linux - session swapping We are running TC 4.1.12 on Linux. We have 8 different websites that run on tomcat. Most of them are low volume. We have encountered the problem where a test engine is executing multiple requests from multiple machines using multiple user accounts against a specific webapp. Sometimes the search results that come back are the search results for a query that was supposed to be ran by one of the other machines. Here is an example. Machine 1 - user 1 -query 1 Machine 2 - user 2 - query 2 machine 1 will sometimes get the results from query 2. The session information holds all of the information. This is from an internal test against a test server so there is no firewall, proxy, etc in the way. I have also been told that this has happened on one of our other web apps also. This time it was a production machine and one of our most used webapps. Any ideas? = Norris Shelton Software Engineer Sun Certified Java 1.1 Programmer Appriss, Inc. ICQ# 26487421 AIM NorrisEShelton YIM norrisshelton __ Do you Yahoo!? Yahoo! Hotjobs: Enter the Signing Bonus Sweepstakes http://hotjobs.sweepstakes.yahoo.com/signingbonus - To unsubscribe, e-mail: [EMAIL PROTECTED] For additional commands, e-mail: [EMAIL PROTECTED] - To unsubscribe, e-mail: [EMAIL PROTECTED] For additional commands, e-mail: [EMAIL PROTECTED] = Norris Shelton Software Engineer Sun Certified Java 1.1 Programmer Appriss, Inc. ICQ# 26487421 AIM NorrisEShelton YIM norrisshelton __ Do you Yahoo!? Yahoo! Hotjobs: Enter the Signing Bonus Sweepstakes http://hotjobs.sweepstakes.yahoo.com/signingbonus - To unsubscribe, e-mail: [EMAIL PROTECTED] For additional commands, e-mail: [EMAIL PROTECTED]
Re: TC 4.1.12 on Linux - session swapping
They are being posted to the same JSP. There are several beans that are page scope. Think that is it? I have a newer part that was written by me that uses request and session scope beans. I will have the QA person run her tests against that part of the project. I am assuming that this will be OK. If so, I will change the page scope beans to be request scope beans. Hopefully the problem will go away. I had noticed on other servers that if you have a request scope beans and you post back to the same page, you sometimes get back the same request. Usually not a problem, because it is yours. However, if this happens for page scope, then real bad, because everyone uses the page. I will let you know what we find. --- QM [EMAIL PROTECTED] wrote: : machine 1 will sometimes get the results from query 2. Smells like an instance/global variable where there shouldn't be one. Add that to a subtle race condition and you have the problem you've outlined. Are the queries being posted to the same servlet? -QM -- software -- http://www.brandxdev.net (C++ / Java / SSL) tech news -- http://www.RoarNetworX.com - To unsubscribe, e-mail: [EMAIL PROTECTED] For additional commands, e-mail: [EMAIL PROTECTED] = Norris Shelton Software Engineer Sun Certified Java 1.1 Programmer Appriss, Inc. ICQ# 26487421 AIM NorrisEShelton YIM norrisshelton __ Do you Yahoo!? Yahoo! Hotjobs: Enter the Signing Bonus Sweepstakes http://hotjobs.sweepstakes.yahoo.com/signingbonus - To unsubscribe, e-mail: [EMAIL PROTECTED] For additional commands, e-mail: [EMAIL PROTECTED]
Re: TC 4.1.12 on Linux - session swapping
: I took a look at the code. UGLY. All of the code is in the JSP : and there are no class variables. Well, if it's all in one JSP, at least you have only one file to check. ;) Sorry, couldn't resist... : There are lots of page scope : beans. Page scope is not something that I am used to using. I : usually use request. Probably not -- page scope is the least-likely culprit of thread concerns, because it's the smallest of the scopes: application session request page So a page-scoped object exists only for that request (e.g. page hit) of that JSP. I'd check the functions that put the objects in the scope for problems. This is a contrived example but make sure any object factories are returning new or properly-recycled objects. Most likely, though, it's a problem with a request- or session- scoped attribute... those are the only ones that get passed around between forward()'s or requests... -QM -- software -- http://www.brandxdev.net (C++ / Java / SSL) tech news -- http://www.RoarNetworX.com - To unsubscribe, e-mail: [EMAIL PROTECTED] For additional commands, e-mail: [EMAIL PROTECTED]
TC 4.1.12 on Linux - session swapping
We are running TC 4.1.12 on Linux. We have 8 different websites that run on tomcat. Most of them are low volume. We have encountered the problem where a test engine is executing multiple requests from multiple machines using multiple user accounts against a specific webapp. Sometimes the search results that come back are the search results for a query that was supposed to be ran by one of the other machines. Here is an example. Machine 1 - user 1 -query 1 Machine 2 - user 2 - query 2 machine 1 will sometimes get the results from query 2. The session information holds all of the information. This is from an internal test against a test server so there is no firewall, proxy, etc in the way. I have also been told that this has happened on one of our other web apps also. This time it was a production machine and one of our most used webapps. Any ideas? = Norris Shelton Software Engineer Sun Certified Java 1.1 Programmer Appriss, Inc. ICQ# 26487421 AIM NorrisEShelton YIM norrisshelton __ Do you Yahoo!? Yahoo! Hotjobs: Enter the Signing Bonus Sweepstakes http://hotjobs.sweepstakes.yahoo.com/signingbonus - To unsubscribe, e-mail: [EMAIL PROTECTED] For additional commands, e-mail: [EMAIL PROTECTED]
Re: TC 4.1.12 on Linux - session swapping
: machine 1 will sometimes get the results from query 2. Smells like an instance/global variable where there shouldn't be one. Add that to a subtle race condition and you have the problem you've outlined. Are the queries being posted to the same servlet? -QM -- software -- http://www.brandxdev.net (C++ / Java / SSL) tech news -- http://www.RoarNetworX.com - To unsubscribe, e-mail: [EMAIL PROTECTED] For additional commands, e-mail: [EMAIL PROTECTED]
RE: TC 4.1.12 on Linux - session swapping
This has the taste of a thread safety issue. Do you guys happen to run the query against the same servlet? If yes, do you happen to use variables, defined in the servlet class scope in order to extract objects from session? BR -Original Message- From: Norris Shelton [mailto:[EMAIL PROTECTED] Sent: 07 2004 . 16:17 To: 'Tomcat Users List' Subject: TC 4.1.12 on Linux - session swapping We are running TC 4.1.12 on Linux. We have 8 different websites that run on tomcat. Most of them are low volume. We have encountered the problem where a test engine is executing multiple requests from multiple machines using multiple user accounts against a specific webapp. Sometimes the search results that come back are the search results for a query that was supposed to be ran by one of the other machines. Here is an example. Machine 1 - user 1 -query 1 Machine 2 - user 2 - query 2 machine 1 will sometimes get the results from query 2. The session information holds all of the information. This is from an internal test against a test server so there is no firewall, proxy, etc in the way. I have also been told that this has happened on one of our other web apps also. This time it was a production machine and one of our most used webapps. Any ideas? = Norris Shelton Software Engineer Sun Certified Java 1.1 Programmer Appriss, Inc. ICQ# 26487421 AIM NorrisEShelton YIM norrisshelton __ Do you Yahoo!? Yahoo! Hotjobs: Enter the Signing Bonus Sweepstakes http://hotjobs.sweepstakes.yahoo.com/signingbonus - To unsubscribe, e-mail: [EMAIL PROTECTED] For additional commands, e-mail: [EMAIL PROTECTED] - To unsubscribe, e-mail: [EMAIL PROTECTED] For additional commands, e-mail: [EMAIL PROTECTED]
RE: TC 4.1.12 on Linux - session swapping
Howdy, Perhaps a threading bug that causes a race condition to the session information. It could be in tomcat or in your webapp. It'll be hard to come with a test case that always demonstrates this issue, but if you can, please contribute the tiny webapp that illustrates the bug to bugzilla. Yoav Shapira Millennium ChemInformatics -Original Message- From: Norris Shelton [mailto:[EMAIL PROTECTED] Sent: Wednesday, January 07, 2004 9:17 AM To: 'Tomcat Users List' Subject: TC 4.1.12 on Linux - session swapping We are running TC 4.1.12 on Linux. We have 8 different websites that run on tomcat. Most of them are low volume. We have encountered the problem where a test engine is executing multiple requests from multiple machines using multiple user accounts against a specific webapp. Sometimes the search results that come back are the search results for a query that was supposed to be ran by one of the other machines. Here is an example. Machine 1 - user 1 -query 1 Machine 2 - user 2 - query 2 machine 1 will sometimes get the results from query 2. The session information holds all of the information. This is from an internal test against a test server so there is no firewall, proxy, etc in the way. I have also been told that this has happened on one of our other web apps also. This time it was a production machine and one of our most used webapps. Any ideas? = Norris Shelton Software Engineer Sun Certified Java 1.1 Programmer Appriss, Inc. ICQ# 26487421 AIM NorrisEShelton YIM norrisshelton __ Do you Yahoo!? Yahoo! Hotjobs: Enter the Signing Bonus Sweepstakes http://hotjobs.sweepstakes.yahoo.com/signingbonus - To unsubscribe, e-mail: [EMAIL PROTECTED] For additional commands, e-mail: [EMAIL PROTECTED] This e-mail, including any attachments, is a confidential business communication, and may contain information that is confidential, proprietary and/or privileged. This e-mail is intended only for the individual(s) to whom it is addressed, and may not be saved, copied, printed, disclosed or used by anyone else. If you are not the(an) intended recipient, please immediately delete this e-mail from your computer system and notify the sender. Thank you. - To unsubscribe, e-mail: [EMAIL PROTECTED] For additional commands, e-mail: [EMAIL PROTECTED]
