The `PopulateAndValidateSnapshot` function introduced in
f6e2da5fb7 from #19806 has been setting fake
`nTx` and `nChainTx` values that can show up in RPC results (see #29328) and
make `CBlockIndex` state hard to reason about, because it is difficult to know
whether the values are real or fake.
Revert to previous behavior of setting `nTx` and `nChainTx` to 0 when the
values are unknown, instead of faking them.
This commit fixes at least two assert failures in the (pindex->nChainTx ==
pindex->nTx + prev_chain_tx) check that would happen previously. Tests for
these failures are added separately in the next two commits.
Compatibility note: This change could result in -checkblockindex failures if a
snapshot was loaded by a previous version of Bitcoin Core and not fully
validated, because fake nTx values will have been saved to the block index. It
would be pretty easy to avoid these failures by adding some compatibility code
to `LoadBlockIndex` and changing `nTx` values from 1 to 0 when they are fake
(when `(pindex->nStatus & BLOCK_VALID_MASK) < BLOCK_VALID_TRANSACTIONS`), but a
little simpler not to worry about being compatible in this case.
This is done in preparation for the next two commits, where the
CMainSignals are de-globalized.
This avoids adding new constructor arguments to the ChainstateManager
and CTxMemPool classes over the next two commits.
This could also allow future tests that are only interested in the
internal behaviour of the classes to forgo instantiating the signals.
Use SignalInterrupt object instead. There is a slight change in behavior here
because the previous StartShutdown code used to abort on failure and the
new code logs errors instead.
Add NodeContext::shutdown variable and start using it to replace the
kernel::Context::interrupt variable. The latter can't easily be removed right
away but will be removed later in this PR.
Moving the interrupt object from the kernel context to the node context
increases flexibility of the kernel API so it is possible to use multiple
interrupt objects, or avoid creating one if one is not needed. It will also
allow getting rid of the kernel::g_context global later in this PR, replacing
it with a private SignalInterrupt instance in init.cpp
There is no change in behavior in this commit outside of unit tests. In unit
tests there should be no visible change either, but internally now each test
has its own interrupt variable so the variable will be automatically reset
between tests.
In future commits, loading the block index while making use of a
snapshot is contingent on the snapshot being recognized by chainparams.
Ensure all existing unittests that use snapshots use a recognized
snapshot (at height 110).
Co-authored-by: Ryan Ofsky <ryan@ofsky.org>
This allows us to reference assumeutxo configuration by blockhash as
well as height; this is helpful in future changes when we want to
reference assumeutxo configurations before the block index is loaded.
This change makes IsInitialBlockDownload and NotifyHeaderTip functions no
longer tied to individual Chainstate objects. It makes them work with the
ChainstateManager object instead so code is simpler and it is no longer
possible to call them incorrectly with an inactive Chainstate.
This change also makes m_cached_finished_ibd caching easier to reason about,
because now there is only one cached value instead of two (for background and
snapshot chainstates) so the cached IBD state now no longer gets reset when a
snapshot is loaded.
There should be no change in behavior because these functions were always
called on the active ChainState objects.
These changes were discussed previously
https://github.com/bitcoin/bitcoin/pull/27746#discussion_r1246868905 and
https://github.com/bitcoin/bitcoin/pull/27746#discussion_r1237552792 as
possible followups for that PR.
When using assumeutxo and multiple chainstates are active, the background
chainstate should consider all HAVE_DATA blocks that are ancestors of the
snapshotted block and that have more work than the tip as potential candidates.
When using assumeutxo, we only need the background chainstate to consider
blocks that are on the chain leading to the snapshotted block.
Note that this introduces the new invariant that we can only have an assumeutxo
snapshot where the snapshotted blockhash is in our block index. Unknown block
hashes that are somehow passed in will cause assertion failures when processing
new blocks.
Includes test fixes and improvements by Andrew Chow and Fabian Jahr.
Block arrival information (and the preciousblock RPC, a related concept) are
both chainstate-agnostic, so these are moved to ChainstateManager. This should
just be a refactor, without any observable behavior changes.
FatalError replaces what previously was the AbortNode function in
shutdown.cpp.
This commit is part of the libbitcoinkernel project and further removes
the shutdown's and, more generally, the kernel library's dependency on
interface_ui with a kernel notification method. By removing interface_ui
from the kernel library, its dependency on boost is reduced to just
boost::multi_index. At the same time it also takes a step towards
de-globalising the interrupt infrastructure.
Co-authored-by: Russell Yanofsky <russ@yanofsky.org>
Co-authored-by: TheCharlatan <seb.kung@gmail.com>
This is done in addition with the following commit. Both have the goal
of getting rid of direct calls to AbortNode from kernel code. This extra
flushError method is added to notify specifically about errors that
arrise when flushing (syncing) block data to disk. Unlike other
instances, the current calls to AbortNode in the blockstorage flush
functions do not report an error to their callers.
This commit is part of the libbitcoinkernel project and further removes
the shutdown's and, more generally, the kernel library's dependency on
interface_ui with a kernel notification method. By removing interface_ui
from the kernel library, its dependency on boost is reduced to just
boost::multi_index. At the same time it also takes a step towards
de-globalising the interrupt infrastructure.
This and the following commit seek to decouple the libbitcoinkernel
library from the shutdown code. As a library, it should it should have
its own flexible interrupt infrastructure without relying on node-wide
globals.
The commit takes the first step towards this goal by de-globalising
`ShutdownRequested` calls in kernel code.
Co-authored-by: Russell Yanofsky <russ@yanofsky.org>
Co-authored-by: TheCharlatan <seb.kung@gmail.com>
This should make the test less reliant on details of the test setup
-BEGIN VERIFY SCRIPT-
sed -i 's/m_args.GetDataDirNet()/chainman.m_options.datadir/g' src/test/validation_chainstatemanager_tests.cpp
-END VERIFY SCRIPT-
Remove access to the global gArgs for getting the directory in
utxo_snapshot.
This is done in the context of the libbitcoinkernel project, wherein
reliance of libbitcoinkernel code on the global gArgs is incrementally
removed.
This commit is part of the libbitcoinkernel project and seeks to remove
the ChainstateManager's and, more generally, the kernel library's
dependency on interface_ui with options methods in this and the following
few commits. By removing interface_ui from the kernel library, its
dependency on boost is reduced to just boost::multi_index.
Define a new kernel notification class with virtual methods for
notifying about internal kernel events. Create a new file in the node
library for defining a function creating the default set of notification
methods such that these do not need to be re-defined all over the
codebase. As a first step, add a `blockTip` method, wrapping
`uiInterface.NotifyBlockTip`.
Add a blocks_dir field to the BlockManager options. Move functions
relying on the global gArgs to get the blocks_dir into the BlockManager
class.
This should eventually allow users of the BlockManager to not rely on
the global Args and instead pass in their own options.
2b373fe49d docs: update assumeutxo.md (James O'Beirne)
87a1108c81 test: add snapshot completion unittests (James O'Beirne)
d70919a88f refactor: make MempoolMutex() public (James O'Beirne)
7300ced9de log: add LoadBlockIndex() message for assumedvalid blocks (James O'Beirne)
d96c59cc5c validation: add ChainMan logic for completing UTXO snapshot validation (James O'Beirne)
f2a4f3376f move-only-ish: init: factor out chainstate initialization (James O'Beirne)
637a90b973 add Chainstate::HasCoinsViews() (James O'Beirne)
c29f26b47b validation: add CChainState::m_disabled and ChainMan::isUsable (James O'Beirne)
5ee22cdafd add ChainstateManager.GetSnapshot{BaseHeight,BaseBlock}() (James O'Beirne)
Pull request description:
This is part of the [assumeutxo project](https://github.com/bitcoin/bitcoin/projects/11) (parent PR: https://github.com/bitcoin/bitcoin/pull/15606)
Part two of replacing https://github.com/bitcoin/bitcoin/pull/24232.
---
When a user activates a snapshot, the serialized UTXO set data is used to create an "assumed-valid" chainstate, which becomes active in an attempt to get the node to network tip as quickly as possible. Simultaneously in the background, the already-existing chainstate continues "conventional" IBD to both accumulate full block data and serve as a belt-and-suspenders to validate the assumed-valid chainstate.
Once the background chainstate's tip reaches the base block of the snapshot used, we set `m_stop_use` on that chainstate and immediately take the hash of its UTXO set; we verify that this matches the assumeutxo value in the source code. Note that while we ultimately want to remove this background chainstate, we don't do so until the following initialization process, when we again check the UTXO set hash of the background chainstate, and if it continues to match, we remove the (now unnecessary) background chainstate, and move the (previously) assumed-valid chainstate into its place. We then reinitialize the chainstate in the normal way.
As noted in previous comments, we could do the filesystem operations "inline" immediately when the background validation completes, but that's basically just an optimization that saves disk space until the next restart. It didn't strike me as worth the risk of moving chainstate data around on disk during runtime of the node, though maybe my concerns are overblown.
The final result of this completion process is a fully-validated chain, where the only evidence that the user synced using assumeutxo is the existence of a `base_blockhash` file in the `chainstate` directory.
ACKs for top commit:
achow101:
ACK 2b373fe49d
Tree-SHA512: a204e1d6e6932dd83c799af3606b01a9faf893f04e9ee1a36d63f2f1ccfa9118bdc1c107d86976aa0312814267e6a42074bf3e2bf1dead4b2513efc6d955e13d
Also adjusts the previous snapshot chainstate init tests
to account for the fact that the init process is now attempting to
validate and complete background chainstates whose tip is at the
snapshot base block. We use a DisconnectTip() hack to preserve the
nature of the test.
4275195606 De-duplicate add_coin methods to a test util helper (Jon Atack)
9d92c3d7f4 Create InsecureRandMoneyAmount() test util helper (Jon Atack)
81f5ade2a3 Move random test util code from setup_common to random (Jon Atack)
Pull request description:
- Move random test utilities from `setup_common` to a new `random` file, as many tests don't use this code.
- Create a helper to generate semi-random CAmounts up to `MONEY_RANGE` rather than only uint32, and use the helper in the unit tests.
- De-duplicate a shared `add_coin` method by extracting it to a `coins` test utility.
ACKs for top commit:
pinheadmz:
ACK 4275195606
achow101:
ACK 4275195606
john-moffett:
ACK 4275195606
Tree-SHA512: 3ed974251149c7417f935ef2f8865aa0dcc33b281b47522b0f96f1979dff94bb8527957f098fe4d210f40d715c00f29512f2ffe189097102229023b7284a3a27
bf95976061 doc: add note about snapshot chainstate init (James O'Beirne)
e4d7995286 test: add testcases for snapshot initialization (James O'Beirne)
cced4e7336 test: move-only-ish: factor out LoadVerifyActivateChainstate() (James O'Beirne)
51fc9241c0 test: allow on-disk coins and block tree dbs in tests (James O'Beirne)
3c361391b8 test: add reset_chainstate parameter for snapshot unittests (James O'Beirne)
00b357c215 validation: add ResetChainstates() (James O'Beirne)
3a29dfbfb2 move-only: test: make snapshot chainstate setup reusable (James O'Beirne)
8153bd9247 blockmanager: avoid undefined behavior during FlushBlockFile (James O'Beirne)
ad67ff377c validation: remove snapshot datadirs upon validation failure (James O'Beirne)
34d1590331 add utilities for deleting on-disk leveldb data (James O'Beirne)
252abd1e8b init: add utxo snapshot detection (James O'Beirne)
f9f1735f13 validation: rename snapshot chainstate dir (James O'Beirne)
d14bebf100 db: add StoragePath to CDBWrapper/CCoinsViewDB (James O'Beirne)
Pull request description:
This is part of the [assumeutxo project](https://github.com/bitcoin/bitcoin/projects/11) (parent PR: https://github.com/bitcoin/bitcoin/pull/15606)
---
Half of the replacement for #24232. The original PR grew larger than expected throughout the review process.
This change adds the ability to initialize a snapshot-based chainstate during init if one is detected on disk. This is of course unused as of now (aside from in unittests) given that we haven't yet enabled actually loading snapshots.
Don't be scared! There are some big move-only commits in here.
Accompanying changes include:
- moving the snapshot coinsdb directory from being called `chainstate_[base blockhash]` to `chainstate_snapshot`, since we only support one snapshot in use at a time. This simplifies some logic, but it necessitates writing that base blockhash out to a file within the coinsdb dir. See [discussion here](https://github.com/bitcoin/bitcoin/pull/24232#discussion_r832762880).
- adding a simple fix in `FlushBlockFile()` that avoids a crash when attemping to flush to disk before `LoadBlockIndexDB()` is called, which happens when calling `MaybeRebalanceCaches()` during multiple chainstate init.
- improving the unittest to allow testing with on-disk chainstates - necessary to test a simulated restart and re-initialization.
ACKs for top commit:
naumenkogs:
utACK bf95976061
ariard:
Code Review ACK bf9597606
ryanofsky:
Code review ACK bf95976061. Changes since last review: rebasing, switching from CAutoFile to AutoFile, adding comments, switching from BOOST_CHECK to Assert in test util, using chainman.GetMutex() in tests, destroying one ChainstateManager before creating a new one in tests
fjahr:
utACK bf95976061
aureleoules:
ACK bf95976061
Tree-SHA512: 15ae75caf19f8d12a12d2647c52897904d27b265a7af6b4ae7b858592eeadb8f9da6c2394b6baebec90adc28742c053e3eb506119577dae7c1e722ebb3b7bcc0
and also fix spelling in test/lint/lint-locale-dependence.py not caught by the
spelling linter and fix up a paragraph we are touching here in test/README.md.
This CreateAndActivateUTXOSnapshot parameter is necessary once we
perform snapshot completion within ABC, since the existing UpdateTip
test will fail because the IBD chain that has generated the snapshot
will exceed the base of the snapshot.
Being able to test snapshots being loaded into a mostly-uninitialized
datadir allows for more realistic unittest scenarios.
Add functionality for activating a snapshot-based chainstate if one is
detected on-disk.
Also cautiously initialize chainstate cache usages so that we don't
somehow blow past our cache allowances during initialization, then
rebalance at the end of init.
Co-authored-by: Russell Yanofsky <russ@yanofsky.org>
This changes the snapshot's leveldb chainstate dir name from
`chainstate_[blockhash]` to `chainstate_snapshot`. This simplifies
later logic that loads snapshot data, and enforces the limitation
of a single snapshot at any given time.
Since we still need to persis the blockhash of the base block, we
write that out to a file (`chainstate_snapshot/base_blockhash`) for
later use during initialization, so that we can reinitialize the
snapshot chainstate.
Co-authored-by: Russell Yanofsky <russ@yanofsky.org>
This is a refactor, putting the burden to think about thread safety to
the caller. Otherwise, there is a risk that the caller will assume
thread safety where none exists, as is evident in the previous two
commits.
