Retry GET from Redis for messages in the Execution Graph
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Shillaker
requested changes
Nov 26, 2021
| REQUIRE(node.msg.id() == req->mutable_messages()->at(i).id()); | ||
| } | ||
| } | ||
| } |
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This test isn't checking that it will fail when the max retries are hit, which seems like the easier case to check for.
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I add another test that checks that you can't get an execution graph for a message that hasn't been published.
…for it in the tests
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Shillaker
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Nov 30, 2021
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In this PR I fix a race condition that happened when running
Scheduler::getFunctionExecGraph()immediately afterScheduler::getFunctionResult()in a distributed setting.In particular, we sometimes generated the execution graph before all remote executors had published their resulting message. As a consequence,
redis.getwould return an empty byte array, and we'd cast it to an emptyfaabric::Message.I add a naive retry mechanism (bear in mind generating execution graphs is off the hot path), and a test that reproduces the failure with very little retries (in fact 10 tries might be an overkill).