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This is an automatically generated e-mail. To reply, visit:
https://reviews.apache.org/r/60714/
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Review request for Aurora, David McLaughlin, Mehrdad Nurolahzade, Santhosh
Kumar Shanmugham, and Zameer Manji.
Bugs: AURORA-1940
https://issues.apache.org/jira/browse/AURORA-1940
Repository: aurora
Description
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aurora job restart request should be idempotent and retryable.
There was a recent change to the Aurora client to provide "at most once"
instead of "at least once" retries for non-idempotent operations. See:
https://github.com/apache/aurora/commit/f1e25375def5a047da97d8bdfb47a3a9101568f6
Technically, `aurora job restart` is a non-idempotent operation, thus it was
not retried. However, when a transport exception occurs, the operator has to
babysit simple operations like aurora job restart if it were not retried.
Compared to the requests that were causing problems (admin tasks, job creating,
updates, etc.), restarts in general should be retried rather than erring on the
side of caution.
Job restart can be divided into three steps:
- 1. get instance status (getTasksWithoutConfigs)
- 2. restart shards (restartShards)
- 3. watch instance until healthy (getTasksWithoutConfigs)
TTransport exception can be thrown at each of these step, ideally we should
make __ALL__ of the steps above __idempotent__ and retryable.
However, given that the `watch` logic is also used in --wait options of job
create/kill command), making this step retryable will have an impact job
create/kill commands as well. IMO, it's probably OK for us to retry the watch
during job create/kill since the watch step is readonly.
In this CR, I will make the first __TWO__ steps retryable since they are
self-contained in job restart command.
If people are OK with this strategy, I'll make the `watch` step retryable as
well.
Diffs
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src/main/python/apache/aurora/client/api/restarter.py
6600c6b608ee70a02e11ca8550a06b7fb76fd863
src/test/python/apache/aurora/api_util.py
bd6e3a6abb5a2eec621121fc1b4d547c54a9d19d
src/test/python/apache/aurora/client/api/test_restarter.py
a81003e79e090bbfa151431366f5394f405d99eb
src/test/python/apache/aurora/client/cli/test_restart.py
cb4adc55caec354d2cdf6a92ff2dd8a3b4a9eca8
Diff: https://reviews.apache.org/r/60714/diff/1/
Testing
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./build-support/jenkins/build.sh
To test the retry logic, random TTranport exceptions were thrown at the client
side(for all api calls to the scheduler proxy), aurora job restart command was
issued against scheduler, and the output was like:
```
vagrant@aurora:~$ aurora job restart devcluster/vagrant/test/hello
WARN] Transport error communicating with scheduler: Timed out talking to
http://aurora.local:8081/api, retrying...
WARN] Transport error communicating with scheduler: Timed out talking to
http://aurora.local:8081/api, retrying...
INFO] Performing rolling restart of job devcluster/vagrant/test/hello
(instances: [0])
INFO] Restarting instances: [0]
WARN] Transport error communicating with scheduler: Timed out talking to
http://aurora.local:8081/api, retrying...
WARN] Transport error communicating with scheduler: Timed out talking to
http://aurora.local:8081/api, retrying...
INFO] Watching instances: [0]
WARN] Transport error communicating with scheduler: Timed out talking to
http://aurora.local:8081/api, retrying...
INFO] Detected RUNNING instance 0
WARN] Transport error communicating with scheduler: Timed out talking to
http://aurora.local:8081/api, retrying...
WARN] Transport error communicating with scheduler: Timed out talking to
http://aurora.local:8081/api, retrying...
WARN] Transport error communicating with scheduler: Timed out talking to
http://aurora.local:8081/api, retrying...
INFO] Instance 0 has been up and healthy for at least 30 seconds
INFO] All instances were restarted successfully
Job devcluster/vagrant/test/hello restarted successfully
```
Thanks,
Kai Huang
