This PR is part of a series: see the prototype https://github.com/palantir/atlasdb/pull/7000 or the internal RFC for what all of the pieces together are expected to look like. I have tried to separate this feature into reasonably sized components as otherwise it'd probably have a 5k delta or so!
Adding both @LucasIME and @mdaudali on this one as this is somewhere in between the handoff point to read validation, for which we will need/want to work on the snapshot validators.
Before this PR: The checking of pre-commit conditions, and of the immutable timestamp and write locks, is one of the many responsibilities of SnapshotTransaction.
After this PR:
==COMMIT_MSG==
The checking of pre-commit conditions, as well as immutable timestamp and write lock checks are not performed by SnapshotTransaction, but instead abstracted away to a PreCommitRequirementValidator.
==COMMIT_MSG==
Priority: High P2
Concerns / possible downsides (what feedback would you like?): Nothing very much on this one, honestly.
Is documentation needed?: No.
Compatibility
Does this PR create any API breaks (e.g. at the Java or HTTP layers) - if so, do we have compatibility?: I don't think so?
Does this PR change the persisted format of any data - if so, do we have forward and backward compatibility?: No
The code in this PR may be part of a blue-green deploy. Can upgrades from previous versions safely coexist? (Consider restarts of blue or green nodes.): Yes
Does this PR rely on statements being true about other products at a deployment - if so, do we have correct product dependencies on these products (or other ways of verifying that these statements are true)?: Not that I'm aware of
Does this PR need a schema migration? No
Testing and Correctness
What, if any, assumptions are made about the current state of the world? If they change over time, how will we find out?: Nothing in particular
What was existing testing like? What have you done to improve it?: Added new tests for the "new" (newly separated) code.
If this PR contains complex concurrent or asynchronous code, is it correct? The onus is on the PR writer to demonstrate this.: N/A
If this PR involves acquiring locks or other shared resources, how do we ensure that these are always released?: N/A
Execution
How would I tell this PR works in production? (Metrics, logs, etc.): No change expected.
Has the safety of all log arguments been decided correctly?: I think so: exception messages are unsafe
Will this change significantly affect our spending on metrics or logs?: No.
How would I tell that this PR does not work in production? (monitors, etc.): Something bad happens.
If this PR does not work as expected, how do I fix that state? Would rollback be straightforward?: Rollback
If the above plan is more complex than “recall and rollback”, please tag the support PoC here (if it is the end of the week, tag both the current and next PoC):
Scale
Would this PR be expected to pose a risk at scale? Think of the shopping product at our largest stack.: No
Would this PR be expected to perform a large number of database calls, and/or expensive database calls (e.g., row range scans, concurrent CAS)?: No
Would this PR ever, with time and scale, become the wrong thing to do - and if so, how would we know that we need to do something differently?: Not that I'm aware of
Development Process
Where should we start reviewing?: PreCommitRequirementValidator
If this PR is in excess of 500 lines excluding versions lock-files, why does it not make sense to split it?:
Please tag any other people who should be aware of this PR:
@jeremyk-91
@sverma30
@raiju
General
This PR is part of a series: see the prototype https://github.com/palantir/atlasdb/pull/7000 or the internal RFC for what all of the pieces together are expected to look like. I have tried to separate this feature into reasonably sized components as otherwise it'd probably have a 5k delta or so!
Adding both @LucasIME and @mdaudali on this one as this is somewhere in between the handoff point to read validation, for which we will need/want to work on the snapshot validators.
Before this PR: The checking of pre-commit conditions, and of the immutable timestamp and write locks, is one of the many responsibilities of SnapshotTransaction.
After this PR:
==COMMIT_MSG== The checking of pre-commit conditions, as well as immutable timestamp and write lock checks are not performed by SnapshotTransaction, but instead abstracted away to a
PreCommitRequirementValidator. ==COMMIT_MSG==Priority: High P2
Concerns / possible downsides (what feedback would you like?): Nothing very much on this one, honestly.
Is documentation needed?: No.
Compatibility
Does this PR create any API breaks (e.g. at the Java or HTTP layers) - if so, do we have compatibility?: I don't think so?
Does this PR change the persisted format of any data - if so, do we have forward and backward compatibility?: No
The code in this PR may be part of a blue-green deploy. Can upgrades from previous versions safely coexist? (Consider restarts of blue or green nodes.): Yes
Does this PR rely on statements being true about other products at a deployment - if so, do we have correct product dependencies on these products (or other ways of verifying that these statements are true)?: Not that I'm aware of
Does this PR need a schema migration? No
Testing and Correctness
What, if any, assumptions are made about the current state of the world? If they change over time, how will we find out?: Nothing in particular
What was existing testing like? What have you done to improve it?: Added new tests for the "new" (newly separated) code.
If this PR contains complex concurrent or asynchronous code, is it correct? The onus is on the PR writer to demonstrate this.: N/A
If this PR involves acquiring locks or other shared resources, how do we ensure that these are always released?: N/A
Execution
How would I tell this PR works in production? (Metrics, logs, etc.): No change expected.
Has the safety of all log arguments been decided correctly?: I think so: exception messages are unsafe
Will this change significantly affect our spending on metrics or logs?: No.
How would I tell that this PR does not work in production? (monitors, etc.): Something bad happens.
If this PR does not work as expected, how do I fix that state? Would rollback be straightforward?: Rollback
If the above plan is more complex than “recall and rollback”, please tag the support PoC here (if it is the end of the week, tag both the current and next PoC):
Scale
Would this PR be expected to pose a risk at scale? Think of the shopping product at our largest stack.: No
Would this PR be expected to perform a large number of database calls, and/or expensive database calls (e.g., row range scans, concurrent CAS)?: No
Would this PR ever, with time and scale, become the wrong thing to do - and if so, how would we know that we need to do something differently?: Not that I'm aware of
Development Process
Where should we start reviewing?:
PreCommitRequirementValidatorIf this PR is in excess of 500 lines excluding versions lock-files, why does it not make sense to split it?:
Please tag any other people who should be aware of this PR: @jeremyk-91 @sverma30 @raiju