(HACKATHON) sql: inject retry errors with test session var#45224
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knz wants to merge 1 commit intocockroachdb:masterfrom
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(HACKATHON) sql: inject retry errors with test session var#45224knz wants to merge 1 commit intocockroachdb:masterfrom
knz wants to merge 1 commit intocockroachdb:masterfrom
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Previously, retry errors were only produced under contention. This not good for training developers; because in developer environments there is often no natural contention. It's thus possible for a dev to move very far forward with their app without realizing they need to care about retry errors. This patch makes it possible for devs to validate that they have all the necessary retry loops. Client side retry errors are forced; after 3 valid retry iterations (with the `cockroach_restart` savepoint rollback) the transaction is allowed to succeed. This mechanism is only enabled when the (new) session var `retry_errors_enabled` is set to true—and it defaults to false. At this point this feature is restricted to explicit transactions. Release note: None
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This is super cool! I just had two nits about naming/messaging.
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| // CockroachDB extension. | ||
| `retry_errors_enabled`: { | ||
| GetStringVal: makeBoolGetStringValFn(`retry_errors_enabled`), |
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bikeshed/nitpick: 2¢ i'd give this a name like inject_retry_errors that makes it clearer that this controls synthetic/injected errors (i.e. as is, i think you could read this setting as automatically retrying on errors).
| if ex.sessionData.RetryErrorsEnabled && stmt.AST.StatementTag() != "SET" { | ||
| if planner.Txn().Epoch() < ex.state.lastEpoch+3 { | ||
| retryErr := planner.Txn().GenerateForcedRetryableError( | ||
| ctx, "forced by executor") |
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nit: I'd say "injected" by executor since it you might not be sure why it was "forced by executor". In. fact, i'd include the name of the flag in the error too, e.g. "error injected by executor due to <setting_name>".
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Thanks David these are good suggestions. I'll work them in when I get to my terminal again.
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Written with @johnrk
Previously, retry errors were only produced under contention.
This not good for training developers; because in developer
environments there is often no natural contention. It's thus possible
for a dev to move very far forward with their app without realizing
they need to care about retry errors.
This patch makes it possible for devs to validate that they have all
the necessary retry loops. Client side retry errors are forced; after
3 valid retry iterations (with the
cockroach_restartsavepointrollback) the transaction is allowed to succeed. This mechanism is
only enabled when the (new) session var
retry_errors_enabledis setto true—and it defaults to false.
At this point this feature is restricted to explicit transactions.
Release note: None