[jira] Commented: (GERONIMO-4184) In-doubt transaction Id's could be reused during server startup
[ https://issues.apache.org/jira/browse/GERONIMO-4184?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanelfocusedCommentId=13007792#comment-13007792 ] David Jencks commented on GERONIMO-4184: I think this patch will break recovery. The first 8 bytes of the byte arrays in the xid are a long counter, the rest is the tmid. Recovery needs to be able to determine if an xid coming back from an XAResource came from this tm. It does this by matching the bytes after 8 in the global xid with the baseid in the XidFactory. If the base id is different every time you start the tm, there's no way to determine if a branch that has been prepared on an XAResource but not recorded in the tm log came from this tm. I think the problem here is that our documentation is not sufficiently insistent that you NEED to configure multiple geronimo servers using the same RM with DIFFERENT tmids. As long as the above is followed, we could randomize the most significant 2 bytes of the long counter. However I think it would be better to track the counter persistently such as by reserving blocks of say 1024 ids and recording this persistently either in a log record or in a separate file. In-doubt transaction Id's could be reused during server startup --- Key: GERONIMO-4184 URL: https://issues.apache.org/jira/browse/GERONIMO-4184 Project: Geronimo Issue Type: Bug Security Level: public(Regular issues) Components: transaction manager Affects Versions: 2.0, 2.0.1, 2.0.2, 2.1, 2.1.1, 2.1.4 Reporter: Kevan Miller Fix For: Wish List Attachments: GERONIM-4184.patch During server restart, we may reuse an Xid for a transaction which is in-doubt. Potentially confusing a resource manager. We need to insure this does not occur. Simple way is to remember the largest Xid in tran log and start with a larger number. -- This message is automatically generated by JIRA. For more information on JIRA, see: http://www.atlassian.com/software/jira
[jira] Commented: (GERONIMO-4184) In-doubt transaction Id's could be reused during server startup
[ https://issues.apache.org/jira/browse/GERONIMO-4184?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanelfocusedCommentId=13007817#comment-13007817 ] Vamsavardhana Reddy commented on GERONIMO-4184: --- Thanks David. The one doubt I had is if introducing two random bytes along with tmId would break anything. Your comment has clarified that. Essentially the random bytes introduced by fix for GERONIMO-4393 will result in a different tmId each time the server is started and break transaction recovery. (Geronimo server may be immune to this as we use the XidFactoryImpl constructor with tmId as parameter.) How can we make sure that even the generated tmId would be the same for a server instance with subsequent restarts? In-doubt transaction Id's could be reused during server startup --- Key: GERONIMO-4184 URL: https://issues.apache.org/jira/browse/GERONIMO-4184 Project: Geronimo Issue Type: Bug Security Level: public(Regular issues) Components: transaction manager Affects Versions: 2.0, 2.0.1, 2.0.2, 2.1, 2.1.1, 2.1.4 Reporter: Kevan Miller Fix For: Wish List Attachments: GERONIM-4184.patch During server restart, we may reuse an Xid for a transaction which is in-doubt. Potentially confusing a resource manager. We need to insure this does not occur. Simple way is to remember the largest Xid in tran log and start with a larger number. -- This message is automatically generated by JIRA. For more information on JIRA, see: http://www.atlassian.com/software/jira
[jira] Commented: (GERONIMO-4184) In-doubt transaction Id's could be reused during server startup
[ https://issues.apache.org/jira/browse/GERONIMO-4184?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanelfocusedCommentId=13007821#comment-13007821 ] David Jencks commented on GERONIMO-4184: The no-arg constructor is only there for people who don't care about recovery and can't be bothered to set up the tm properly. I guess if we're going to do anything here we should figure out a way to store the baseid and counter range in the tx log (in the log object, not necessarily in the log files) and read them in as part of recovery. Then if there's a recorded baseid we can use it. In-doubt transaction Id's could be reused during server startup --- Key: GERONIMO-4184 URL: https://issues.apache.org/jira/browse/GERONIMO-4184 Project: Geronimo Issue Type: Bug Security Level: public(Regular issues) Components: transaction manager Affects Versions: 2.0, 2.0.1, 2.0.2, 2.1, 2.1.1, 2.1.4 Reporter: Kevan Miller Fix For: Wish List Attachments: GERONIM-4184.patch During server restart, we may reuse an Xid for a transaction which is in-doubt. Potentially confusing a resource manager. We need to insure this does not occur. Simple way is to remember the largest Xid in tran log and start with a larger number. -- This message is automatically generated by JIRA. For more information on JIRA, see: http://www.atlassian.com/software/jira
[jira] Commented: (GERONIMO-4184) In-doubt transaction Id's could be reused during server startup
[ https://issues.apache.org/jira/browse/GERONIMO-4184?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanelfocusedCommentId=13006815#comment-13006815 ] Vamsavardhana Reddy commented on GERONIMO-4184: --- GERONIMO-4393 has introduced two random bytes into the baseId to avoid duplication of baseId across multiple JVMs on the same machine. That fix would still not suffice completely as the two random bytes are added to baseId only if the no-argument constructor of XidFactoryImpl is used and Geronimo uses the other constructor that takes byte[] tmId as argument. If we add two random bytes to baseId even in the case of the constructor with tmId, we can minimize the chance of reuse of In-doubt transaction Id's as the baseId would be different on each run of the server. We can even increase the length of random bytes (to say 4 instead of 2) to further reduce the chance of reuse of In-doubt transaction Id's. Any suggestions or comments to this approach? In-doubt transaction Id's could be reused during server startup --- Key: GERONIMO-4184 URL: https://issues.apache.org/jira/browse/GERONIMO-4184 Project: Geronimo Issue Type: Bug Security Level: public(Regular issues) Components: transaction manager Affects Versions: 2.0, 2.0.1, 2.0.2, 2.1, 2.1.1, 2.1.4 Reporter: Kevan Miller Fix For: Wish List During server restart, we may reuse an Xid for a transaction which is in-doubt. Potentially confusing a resource manager. We need to insure this does not occur. Simple way is to remember the largest Xid in tran log and start with a larger number. -- This message is automatically generated by JIRA. For more information on JIRA, see: http://www.atlassian.com/software/jira
