Opened 8 years ago
Closed 8 years ago
#26933 closed Bug (fixed)
Test for #26804 has a tendency to fail on Oracle databases
Reported by: | Jensen Cochran | Owned by: | Jensen Cochran |
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Component: | Database layer (models, ORM) | Version: | dev |
Severity: | Normal | Keywords: | update_or_create test tests |
Cc: | Triage Stage: | Accepted | |
Has patch: | yes | Needs documentation: | no |
Needs tests: | no | Patch needs improvement: | yes |
Easy pickings: | no | UI/UX: | no |
Description (last modified by )
According to comment on the pull request for #26804 (https://github.com/django/django/pull/6831), the test for the issue (written by me) has a tendency to fail on Oracle databases. The test assumes that the database will take no longer than 50ms to lock the associated row, but it seems that this assumption is incorrect in some cases.
I have written a patch for this that should mostly fix the issue. Instead of assuming the database has locked the row, I set a value in the spawned thread after select_for_update has ran and poll that value in the main thread.
However, there still has to be some kind of timeout as we cannot wait forever for the database to lock the row. I have set that timeout at 0.5 seconds and have changed the thread/callable sleep time to 0.5 seconds as well to allow for more room for slow databases. There is no reason to have the timeout be any longer than the thread sleep time, because once the main thread waits that long the assertion would pass no matter what anyway. If the timeout expires the test is skipped.
Alternatively, I could fail if the timeout occurs, but this has potential to fail somewhat randomly as it is doing now.
If update_or_create were ever changed such that the locking behavior was removed, the test would fail as expected so it should still serve its purpose.
Attachments (1)
Change History (7)
comment:1 by , 8 years ago
Owner: | set to |
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Status: | new → assigned |
comment:2 by , 8 years ago
Description: | modified (diff) |
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by , 8 years ago
Attachment: | 26933.diff added |
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comment:3 by , 8 years ago
Triage Stage: | Unreviewed → Accepted |
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comment:4 by , 8 years ago
Alright thanks, I will make sure to do that in the future. Pull request is up.
For future reference, it would be fine to send a pull request that simply references the original ticket (since that hasn't been release yet) rather than opening a new ticket. Can you send a pull request?