The total difficulty is the sum of all block difficulties from genesis
to a certain block. This value was used in PoW for deciding which chain
is heavier, and thus which chain to select. Since PoS has a different
fork selection algorithm, all blocks since the merge have a difficulty
of 0, and all total difficulties are the same for the past 2 years.
Whilst the TDs are mostly useless nowadays, there was never really a
reason to mess around removing them since they are so tiny. This
reasoning changes when we go down the path of pruned chain history. In
order to reconstruct any TD, we **must** retrieve all the headers from
chain head to genesis and then iterate all the difficulties to compute
the TD.
In a world where we completely prune past chain segments (bodies,
receipts, headers), it is not possible to reconstruct the TD at all. In
a world where we still keep chain headers and prune only the rest,
reconstructing it possible as long as we process (or download) the chain
forward from genesis, but trying to snap sync the head first and
backfill later hits the same issue, the TD becomes impossible to
calculate until genesis is backfilled.
All in all, the TD is a messy out-of-state, out-of-consensus computed
field that is overall useless nowadays, but code relying on it forces
the client into certain modes of operation and prevents other modes or
other optimizations. This PR completely nukes out the TD from the node.
It doesn't compute it, it doesn't operate on it, it's as if it didn't
even exist.
Caveats:
- Whenever we have APIs that return TD (devp2p handshake, tracer, etc.)
we return a TD of 0.
- For era files, we recompute the TD during export time (fairly quick)
to retain the format content.
- It is not possible to "verify" the merge point (i.e. with TD gone, TTD
is useless). Since we're not verifying PoW any more, just blindly trust
it, not verifying but blindly trusting the many year old merge point
seems just the same trust model.
- Our tests still need to be able to generate pre and post merge blocks,
so they need a new way to split the merge without TTD. The PR introduces
a settable ttdBlock field on the consensus object which is used by tests
as the block where originally the TTD happened. This is not needed for
live nodes, we never want to generate old blocks.
- One merge transition consensus test was disabled. With a
non-operational TD, testing how the client reacts to TTD is useless, it
cannot react.
Questions:
- Should we also drop total terminal difficulty from the genesis json?
It's a number we cannot react on any more, so maybe it would be cleaner
to get rid of even more concepts.
---------
Co-authored-by: Gary Rong <garyrong0905@gmail.com>
This PR changes how sidechains are handled.
Before the merge, it was possible to import a chain with lower td and not set it as canonical. After the merge, we expect every chain that we get via InsertChain to be canonical. Non-canonical blocks can still be inserted
with InsertBlockWIthoutSetHead.
If during the InsertChain, the existing chain is not canonical anymore, we mark it as a sidechain and send the SideChainEvents normally.
* all: add stateless verifications
* all: simplify witness and integrate it into live geth
---------
Co-authored-by: Péter Szilágyi <peterke@gmail.com>
There were several problems related to dumping state.
- If a preimage was missing, even if we had set the `OnlyWithAddresses` to `false`, to export them anyway, the way the mapping was constructed (using `common.Address` as key) made the entries get lost anyway. Concerns both state- and blockchain tests.
- Blockchain test execution was not configured to store preimages.
This changes makes it so that the block test executor takes a callback, just like the state test executor already does. This callback can be used to examine the post-execution state, e.g. to aid debugging of test failures.
* cmd/evm: make evm blocktest output logs if so instructed
* Apply suggestions from code review
Co-authored-by: Marius van der Wijden <m.vanderwijden@live.de>
---------
Co-authored-by: Marius van der Wijden <m.vanderwijden@live.de>
This PR builds on #26299, but also updates the tests to the most recent version, which includes tests regarding TheMerge.
This change adds checks to the beacon consensus engine, making it more strict in validating the pre- and post-headers, and not relying on the caller to have already correctly sanitized the headers/blocks.
This updates the consensus tests to commit 31d6630 and
adds support for access list transactions in the test runner.
Co-authored-by: Martin Holst Swende <martin@swende.se>
Removes the yolov2 definition, adds yolov3, including EIP-2565. This PR also disables some of the erroneously generated blockchain and statetests, and adds the new genesis hash + alloc for yolov3.
This PR disables the CLI switches for yolo, since it's not complete until we merge support for 2930.
* update tests for istanbul
* tests: updated blockchaintests, see https://github.com/ethereum/tests/issues/637
* tests: update again, hopefully fixed this time
* tests: skip time consuming, run legacy tests
* tests: update again
* build: disable long-running tests on travis
* tests: fix formatting nits
* tests: I hate github's editor
This commit does a few things at once:
- Updates the tests to contain the latest data from ethereum/tests repo.
- Enables Constantinople state tests. This is needed to be able to
fuzz-test the evm with constantinople rules.
- Fixes the error in opSAR that we've known about for some time. I was
kind of saving it to see if we hit upon it with the random test
generator, but it's difficult to both enable the tests and have the
bug there -- we don't want to forget about it, so maybe it's better
to just fix it.
* params: Updated finalized gascosts for ECMUL/MODEXP
* core,tests: Updates pending new tests
* tests: Updated with new tests
* core: revert state transition bugfix
* tests: Add expected failures due to #15119
Blockchain tests now include the "network" which determines the chain
config to use. Remove config matching based on test name and share the
name-to-config index with state tests.
Byzantium/Constantinople tests are still skipped because most of them
fail anyway.
Tests are now included as a submodule. This should make updating easier
and removes ~60MB of JSON data from the working copy.
State tests are replaced by General State Tests, which run the same test
with multiple fork configurations.
With the new test runner, consensus tests are run as subtests by walking
json files. Many hex issues have been fixed upstream since the last
update and most custom parsing code is replaced by existing JSON hex
types. Tests can now be marked as 'expected failures', ensuring that
fixes for those tests will trigger an update to test configuration. The
new test runner also supports parallel execution and the -short flag.
This implements 1b & 1c of EIP150 by adding a new GasTable which must be
returned from the RuleSet config method. This table is used to determine
the gas prices for the current epoch.
Please note that when the CreateBySuicide gas price is set it is assumed
that we're in the new epoch phase.
In addition this PR will serve as temporary basis while refactorisation
in being done in the EVM64 PR, which will substentially overhaul the gas
price code.
Two new tests are skipped because they're buggy. Making some newer
random state tests work required implementing the 'compressed return
value encoding'.
Added chain configuration options and write out during genesis database
insertion. If no "config" was found, nothing is written to the database.
Configurations are written on a per genesis base. This means
that any chain (which is identified by it's genesis hash) can have their
own chain settings.