Use to replace m_active_chainstate, m_ibd_chainstate, and m_snapshot_chainstate
members. This has several benefits:
- Ensures ChainstateManager treats chainstates instances equally, making
distinctions based on their attributes, not having special cases and making
assumptions based on their identities.
- Normalizes ChainstateManager representation so states that should be
impossible to reach and validation code has no handling for (like
m_snapshot_chainstate being set and m_ibd_chainstate being unset, or both
being set but m_active_chainstate pointing to the m_ibd_chainstate) can no
longer be represented.
- Makes ChainstateManager more extensible so new chainstates can be added for
different purposes, like indexing or generating and validating assumeutxo
snapshots without interrupting regular node operations. With the
m_chainstates member, new chainstates can be added and handled without needing
to make changes all over validation code or to copy/paste/modify the existing
code that's been already been written to handle m_ibd_chainstate and
m_snapshot_chainstate.
- Avoids terms that are confusing and misleading:
- The term "active chainstate" term is confusing because multiple chainstates
will be active and in use at the same time. Before a snapshot is validated,
wallet code will use the snapshot chainstate, while indexes will use the IBD
chainstate, and netorking code will use both chainstates, downloading
snapshot blocks at higher priority, but also IBD blocks simultaneously.
- The term "snapshot chainstate" is ambiguous because it could refer either
to the chainstate originally loaded from a snapshot, or to the chainstate
being used to validate a snapshot that was loaded, or to a chainstate being
used to produce a snapshot, but it is arbitrary used to refer the first
thing. The terms "most-work chainstate" or "assumed-valid chainstate" should
be less ambiguous ways to refer to chainstates loaded from snapshots.
- The term "IBD chainstate" is not just ambiguous but actively confusing
because technically IBD ends and the node is considered synced when the
snapshot chainstate finishes syncing, so in practice the IBD chainstate
will mostly by synced after IBD is complete. The term "fully-validated" is
a better way of describing the characteristics and purpose of this
chainstate.
IsSnapshotValidated() is only called one place outside of tests, and is use
redundantly in some tests, asserting that a snapshot is not validated when a
snapshot chainstate does not even exist. Simplify by dropping the method and
checking Chainstate m_assumeutxo field directly.
IsSnapshotActive() method is only called one place outside of tests and
asserts, and is confusing because it returns true even after the snapshot is
fully validated.
The documentation which said this "implies that a background validation
chainstate is also in use" is also incorrect, because after the snapshot is
validated, the background chainstate gets disabled and IsUsable() would return
false.
Use to simplify code determining the chainstate leveldb paths. New method is
the now the only code that needs to figure out the storage path, so the path
doesn't need to be constructed multiple places and backed out of leveldb.
Remove hardcoded references to m_ibd_chainstate and m_snapshot_chainstate so
MaybeCompleteSnapshotValidation function can be simpler and focus on validating
the snapshot without dealing with internal ChainstateManager states.
This is a step towards being able to validate the snapshot outside of
ActivateBestChain loop so cs_main is not locked for minutes when the snapshot
block is connected.
Make Chainstate objects aware of what block they are targeting. This makes
Chainstate objects more self contained, so it's possible for validation code to
look at one Chainstate object and know what blocks to connect to it without
needing to consider global validation state or look at other Chainstate
objects.
The motivation for this change is to make validation and networking code more
readable, so understanding it just requires knowing about chains and blocks,
not reasoning about assumeutxo download states. This change also enables
simplifications to the ChainstateManager interface in subsequent commits, and
could make it easier to implement new features like creating new Chainstate
objects to generate UTXO snapshots or index UTXO data.
Note that behavior of the MaybeCompleteSnapshotValidation function is not
changing here but some checks that were previously impossible to trigger like
the BASE_BLOCKHASH_MISMATCH case have been turned into asserts.
It is redundant with -logsourcelocations and the log messages are
clearer without it.
Also, remove a double-space.
Also, add braces around `if` touched in the next commit.
This tiny behavior change requires a test fixup.
Make the block db open RAII style by calling it in the BlockManager
constructor.
Before this change the block tree db was needlessly re-opened during
startup when loading a completed snapshot. Improve this by letting the
block manager open it on construction. This also simplifies the test
code a bit.
The change was initially motivated to make it easier for users of the
kernel library to instantiate a BlockManager that may be used to read
data from disk without loading the block index into a cache.
This commit is done in preparation for the next commit. Here, the block
tree options are moved to the blockmanager options and the block tree is
instantiated through a helper method of the BlockManager, which is
removed again in the next commit.
Co-authored-by: MarcoFalke <*~=`'#}+{/-|&$^_@721217.xyz>
The check for whether the block tree db has been wiped before calling
NeedsRedownload() is confusing. The boolean is set in case of a reindex.
It was originally introduced to guard NeedsRedownload in case of a
reindex in #21009. However NeedsRedownload already returns early if the
chain's tip is not loaded. Since that is the case during a reindex, the
pre-check is redundant.
This avoids having to rely on implicit casts when passing them to the
various functions allocating the caches.
This also ensures that if the requested amount of db_cache does not fit
in a size_t, it is clamped to the maximum value of a size_t.
Also take this opportunity to make the total amounts of cache in the
chainstate manager a size_t too.
Carrying non-kernel related fields in the cache sizes for the indexes is
confusing for kernel library users. The cache sizes also are set
currently with magic numbers in bitcoin-chainstate. The comments for the
cache size calculations are also not completely clear.
Solve these things by moving the kernel-specific cache size fields to
their own struct.
This slightly changes the way the cache is allocated if the txindex
and/or blockfilterindex is used. Since they are now given precedence
over the block tree db cache, this results in a bit less cache being
allocated to the block tree db, coinsdb and coins caches. The effect is
negligible though, i.e. cache sizes with default dbcache reported
through the logs are:
master:
Cache configuration:
* Using 2.0 MiB for block index database
* Using 56.0 MiB for transaction index database
* Using 49.0 MiB for basic block filter index database
* Using 8.0 MiB for chain state database
* Using 335.0 MiB for in-memory UTXO set (plus up to 286.1 MiB of unused mempool space)
this branch:
Cache configuration:
* Using 2.0 MiB for block index database
* Using 56.2 MiB for transaction index database
* Using 49.2 MiB for basic block filter index database
* Using 8.0 MiB for chain state database
* Using 334.5 MiB for in-memory UTXO set (plus up to 286.1 MiB of unused mempool space)
3a4a788ee0db83d20607f14801dbed2ee932943c init: Correct coins db cache size setting (TheCharlatan)
Pull request description:
The chainstate caches are currently re-balanced on startup even in the non-assumeutxo case, leading to the database being needlessly re-opened and its cache re-allocated.
Similar to `InitCoinsCache` and `m_coinstip_cache_size_bytes`, the `m_coinsdb_cache_size_bytes` should be set in `InitCoinsDB`.
Together with only conservatively setting the cache values when a assumeutxo chainstate is present, this allows for skipping the cache re-balance during initialization in the normal non-assumeutxo case.
Before:
```
2024-10-09T21:22:17Z Checking all blk files are present...
2024-10-09T21:22:17Z Initializing chainstate Chainstate [ibd] @ height -1 (null)
2024-10-09T21:22:17Z Opening LevelDB in /home/drgrid/.bitcoin/signet/chainstate
2024-10-09T21:22:17Z Opened LevelDB successfully
2024-10-09T21:22:17Z Using obfuscation key for /home/drgrid/.bitcoin/signet/chainstate: b0a6f4e95fd05c92
2024-10-09T21:22:17Z Loaded best chain: hashBestChain=0000000e119967d4937dad58456885ae43fb1761db686947e2f8e168c9a39a4f height=216852 date=2024-10-09T21:06:16Z progress=0.999989
2024-10-09T21:22:17Z Opening LevelDB in /home/drgrid/.bitcoin/signet/chainstate
2024-10-09T21:22:17Z Opened LevelDB successfully
2024-10-09T21:22:17Z Using obfuscation key for /home/drgrid/.bitcoin/signet/chainstate: b0a6f4e95fd05c92
2024-10-09T21:22:17Z [Chainstate [ibd] @ height 216852 (0000000e119967d4937dad58456885ae43fb1761db686947e2f8e168c9a39a4f)] resized coinsdb cache to 8.0 MiB
2024-10-09T21:22:17Z [Chainstate [ibd] @ height 216852 (0000000e119967d4937dad58456885ae43fb1761db686947e2f8e168c9a39a4f)] resized coinstip cache to 440.0 MiB
2024-10-09T21:22:17Z init message: Verifying blocks…
```
After:
```
2024-10-09T21:21:37Z Checking all blk files are present...
2024-10-09T21:21:37Z Initializing chainstate Chainstate [ibd] @ height -1 (null)
2024-10-09T21:21:37Z Opening LevelDB in /home/drgrid/.bitcoin/signet/chainstate
2024-10-09T21:21:37Z Opened LevelDB successfully
2024-10-09T21:21:37Z Using obfuscation key for /home/drgrid/.bitcoin/signet/chainstate: b0a6f4e95fd05c92
2024-10-09T21:21:37Z Loaded best chain: hashBestChain=0000012c12b48011a7d9150ce96ed6a44bbf32b09eeecaff4a667789dda2a566 height=216850 date=2024-10-09T20:37:05Z progress=0.999971
2024-10-09T21:21:37Z init message: Verifying blocks…
```
The change may also be verified by looking at the `feature_assumeutxo.py` functional test debug logs.
ACKs for top commit:
fjahr:
utACK 3a4a788ee0db83d20607f14801dbed2ee932943c
achow101:
ACK 3a4a788ee0db83d20607f14801dbed2ee932943c
laanwj:
Code review ACK 3a4a788ee0db83d20607f14801dbed2ee932943c
BrandonOdiwuor:
Code Review ACK 3a4a788ee0db83d20607f14801dbed2ee932943c
Tree-SHA512: 87878d0d196bb426370d4b4bd180ca52a34017a0799ecea651c2532461fd2927b0f7cc8182276a7d9bb1fe0ede7d0ad677e3714ca22f321917d711c643acc578
The chainstate caches are currently re-balanced on startup
even in the non-assumeutxo case, leading to the database being
needlessly re-opened and its cache re-allocated.
Similar to `InitCoinsCache` and `m_coinstip_cache_size_bytes` the
`m_coinsdb_cache_size_bytes` should be set in `InitCoinsDB`.
Together with only conservatively setting the cache values when a
assumeutxo chainstate is present, this allows for skipping the cache
re-balance during initialization in the normal non-assumeutxo case.
This is a just a mechanical change, renaming and inverting the meaning
of the indexing variable.
"m_blockfiles_indexed" is a more straightforward name for this variable
because this variable just indicates whether or not
<datadir>/blocks/blk?????.dat files have been indexed in the
<datadir>/blocks/index LevelDB database. The name "m_reindexing" was
more confusing, it could be true even if -reindex was not specified, and
false when it was specified. Also, the previous name unnecessarily
required thinking about the whole reindexing process just to understand
simple checks in validation code about whether blocks were indexed.
The motivation for this change is to follow up on previous commits,
moving away from having multiple variables called "reindex" internally,
and instead naming variables individually after what they do and
represent.
Drop confusing kernel options:
BlockManagerOpts::reindex
ChainstateLoadOptions::reindex
ChainstateLoadOptions::reindex_chainstate
Replacing them with more straightforward options:
ChainstateLoadOptions::wipe_block_tree_db
ChainstateLoadOptions::wipe_chainstate_db
Having two options called "reindex" which did slightly different things
was needlessly confusing (one option wiped the block tree database, and
the other caused block files to be rescanned). Also the previous set of
options did not allow rebuilding the block database without also
rebuilding the chainstate database, when it should be possible to do
those independently.
fReindex is one of the last remaining globals exposed by the kernel
library, so move it into the blockstorage class to reduce the amount of
global mutable state and make the kernel library a bit less awkward to
use.
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.
The thread does not only load blocks, it loads the mempool and,
in a future commit, will start the indexes as well.
Also, renamed the 'ThreadImport' function to 'ImportBlocks'
And the 'm_load_block' class member to 'm_thread_load'.
-BEGIN VERIFY SCRIPT-
sed -i "s/ThreadImport/ImportBlocks/g" $(git grep -l ThreadImport -- ':!/doc/')
sed -i "s/loadblk/initload/g" $(git grep -l loadblk -- ':!/doc/release-notes/')
sed -i "s/m_load_block/m_thread_load/g" $(git grep -l m_load_block)
-END VERIFY SCRIPT-
Make LoadChainstate return an explicit error when snapshot validation succeeds,
but there is an error trying to replace the background chainstate with the
snapshot chainstate. Previously in this case LoadChainstate would trigger a
shutdown and return INTERRUPTED, now it will return an actual error code.
There's no real change to behavior other than error message being formatted a
little differently.
Motivation for this change is to replace error handling via callbacks with
error handling via return value ahead of
https://github.com/bitcoin/bitcoin/pull/27861
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.
This is a commit in preparation for the next few commits. The functions
are moved to methods to avoid their re-declaration for the purpose of
passing in BlockManager options.
The functions that were now moved into the BlockManager should no longer
use the params as an argument, but instead use the member variable.
In the moved ReadBlockFromDisk and UndoReadFromDisk, change
the function signature to accept a reference to a CBlockIndex instead of
a raw pointer. The pointer is expected to be non-null, so reflect that
in the type.
To allow for the move of functions to BlockManager methods all call
sites require an instantiated BlockManager, or a callback to one.
The fs.* files are already part of the libbitcoin_util library. With the
introduction of the fs_helpers.* it makes sense to move fs.* into the
util/ directory as well.
2b373fe49d64f04ceab2309d3f40da7bac6b37d6 docs: update assumeutxo.md (James O'Beirne)
87a1108c81fe0cb15c3860e3a67dc1f43ffec705 test: add snapshot completion unittests (James O'Beirne)
d70919a88fc90a2662f9a844deb085d03ee7b5d8 refactor: make MempoolMutex() public (James O'Beirne)
7300ced9de22e6d1bff816e6538d3370cebe7501 log: add LoadBlockIndex() message for assumedvalid blocks (James O'Beirne)
d96c59cc5cd2f73f1f55c133c52208671fe75ef3 validation: add ChainMan logic for completing UTXO snapshot validation (James O'Beirne)
f2a4f3376f1476b38a79a549bd81ba3006225df6 move-only-ish: init: factor out chainstate initialization (James O'Beirne)
637a90b973f60555ea4fef4b845ffa7533dcb866 add Chainstate::HasCoinsViews() (James O'Beirne)
c29f26b47b8ef978d8689dc0222aa663361ee6cb validation: add CChainState::m_disabled and ChainMan::isUsable (James O'Beirne)
5ee22cdafd2562bcb8bf0ae6025e4b53c826382d 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 2b373fe49d64f04ceab2309d3f40da7bac6b37d6
Tree-SHA512: a204e1d6e6932dd83c799af3606b01a9faf893f04e9ee1a36d63f2f1ccfa9118bdc1c107d86976aa0312814267e6a42074bf3e2bf1dead4b2513efc6d955e13d
Trigger completion when a background validation chainstate reaches the
same height as a UTXO snapshot, and handle cleaning up the chainstate
on subsequent startup.
0af16e7134459e0820ab95d751093876c1ec4c6d doc: add release note for #25574 (Martin Zumsande)
57ef2a4812f443b2d734f43cebf3ef5038da83f2 validation: report if pruning prevents completion of verification (Martin Zumsande)
0c7785bb2540b69564104767d38342704230cbc2 init, validation: Improve handling if VerifyDB() fails due to insufficient dbcache (Martin Zumsande)
d6f781f1cfcbc2c2ad5ee289a0642ed00386d013 validation: return VerifyDBResult::INTERRUPTED if verification was interrupted (Martin Zumsande)
6360b5302d2675788de5c4a28ea77d823f6d809e validation: Change return value of VerifyDB to enum type (Martin Zumsande)
Pull request description:
`VerifyDB()` can fail to complete due to insufficient dbcache at the level 3 checks. This PR improves the error handling in this case in the following ways:
- The rpc `-verifychain` now returns false if the check can't be completed due to insufficient cache
- During init, we only log a warning if the default values for `-checkblocks` and `-checklevel` are taken and the check doesn't complete. However, if the user actively specifies one of these args, we return with an InitError if we can't complete the check.
This PR also changes `-verifychain` RPC to return `false` if the verification didn't finish due to missing block data (pruning) or due to being interrupted by the node being shutdown.
Previously, this PR also included a fix for a possible assert during verification - this was done in #27009 (now merged).
ACKs for top commit:
achow101:
ACK 0af16e7134459e0820ab95d751093876c1ec4c6d
ryanofsky:
Code review ACK 0af16e7134459e0820ab95d751093876c1ec4c6d. Only small suggested changes since the last review, like renaming some of the enum values. I did leave more suggestions, but they are not very important and could be followups
john-moffett:
ACK 0af16e7134459e0820ab95d751093876c1ec4c6d
MarcoFalke:
lgtm re-ACK 0af16e7134459e0820ab95d751093876c1ec4c6d 🎚
Tree-SHA512: 84b4f767cf9bfbafef362312757c9bf765b41ae3977f4ece840e40c52a2266b1457832df0cdf70440be0aac2168d9b58fc817238630b0b6812f3836ca950bc0e
Moves chainstate initialization into its own function. This is
necessary to later support a more readable way of handling
background-validation chainstate cleanup during init, since the
chainstate initialization functions may need to be repeated after
moving leveldb filesystem content around.
This commit isn't strictly necessary, but the alternative is to (ab)use
the `while` loop in init.cpp with a `continue` on the basis of a
specific ChainstateLoadingError return value from LoadChainstate. Not
only is this harder to read, but it can't be unittested.
The approach here lets us consolidate background-validation cleanup to
LoadChainstate, and therefore exercise it within tests.
This commit is most easily reviewed with
git diff --color-moved=dimmed-zebra
--color-moved-ws=ignore-space-change
The rpc command verifychain now fails if the dbcache was not sufficient
to complete the verification at the specified level and depth.
In the same situation, the VerifyDB check during Init will now fail (and lead to
an early shutdown) if the user has explicitly specified -checkblocks or
-checklevel but the check couldn't be executed because of the limited
cache. If the user didn't change any of the two and is using the defaults, log a warning
but don't prevent the node from starting up.
This does not change behavior. It is in preparation for
special handling of the case where VerifyDB doesn't finish
for various reasons, but doesn't fail.
Use DBParams struct to remove ArgsManager uses from txdb.
To reduce size of this commit, this moves references to gArgs variable out of
txdb.cpp to calling code in chainstate.cpp. But these moves are temporary. The
gArgs references in chainstate.cpp are moved out to calling code in init.cpp in
later commits.
This commit does not change behavior.
This changes the minimum chain work for the bitcoin-chainstate
executable. Previously it was uint256{}, now it is the chain's default
minimum chain work.
