Uploaded image for project: 'Data Management'
  1. Data Management
  2. DM-17147

SAL numpy array data corruption

    XMLWordPrintable

    Details

      Description

      While trying to collect data from SAL with python I uncovered an issue with the numpy arrays. If you cache the array directly from the data structure (for example, to get an average of the data) you will get bad numbers. The issue appears to relate to garbage collection and the SAL data structure being collected while something else still holds a reference to the numpy arrays contained by that data structure.

      Attached is an example python file that has 3 ways of caching the data.

      I also tried a change in which I print the min/max of the first data cached while adding more data to the cache. What I found is the min / max of the first set of data cached changes. I have attached an image of it.

        Attachments

          Issue Links

            Activity

            ccontaxis Christopher Contaxis [X] (Inactive) created issue -
            ccontaxis Christopher Contaxis [X] (Inactive) made changes -
            Field Original Value New Value
            Attachment m1m3_ForceActuatorData_Subscriber.py [ 36594 ]
            ccontaxis Christopher Contaxis [X] (Inactive) made changes -
            Attachment SALPY_Issue.png [ 36595 ]
            swinbank John Swinbank made changes -
            Team Telescope and Site [ 13500 ]
            jbuffill James Buffill [X] (Inactive) made changes -
            Epic Link DM-17218 [ 238992 ]
            jbuffill James Buffill [X] (Inactive) made changes -
            Epic Link DM-17218 [ 238992 ] DM-17100 [ 238784 ]
            jbuffill James Buffill [X] (Inactive) made changes -
            End date 13/Feb/19
            Start date 11/Jan/19
            jbuffill James Buffill [X] (Inactive) made changes -
            Epic Link DM-17100 [ 238784 ] DM-17151 [ 238905 ]
            jbuffill James Buffill [X] (Inactive) made changes -
            Labels M1M3 Mirror testing
            rowen Russell Owen made changes -
            Remote Link This issue links to "Page (Confluence)" [ 19885 ]
            jbuffill James Buffill [X] (Inactive) made changes -
            Epic Link DM-17151 [ 238905 ] DM-17218 [ 238992 ]
            jbuffill James Buffill [X] (Inactive) made changes -
            End date 13/Feb/19 13/Feb/19
            aclements Andy Clements made changes -
            Epic Link DM-17218 [ 238992 ] DM-20191 [ 326477 ]
            dmills Dave Mills made changes -
            Labels M1M3 Mirror testing M1M3 Mirror SAL testing
            dmills Dave Mills made changes -
            Resolution Done [ 10000 ]
            Status To Do [ 10001 ] Won't Fix [ 10405 ]

              People

              Assignee:
              dmills Dave Mills
              Reporter:
              ccontaxis Christopher Contaxis [X] (Inactive)
              Watchers:
              Christopher Contaxis [X] (Inactive), Dave Mills, Rob Bovill, Russell Owen
              Votes:
              0 Vote for this issue
              Watchers:
              4 Start watching this issue

                Dates

                Created:
                Updated:
                Resolved:
                Start date:
                End date:

                  Jenkins

                  No builds found.