When using an assumedvalid (snapshot) chainstate along with a background
chainstate, we are syncing two very different regions of the chain
simultaneously. If we use the same blockfile space for both of these
syncs, wildly different height blocks will be stored alongside one
another, making pruning ineffective.
This change implements a separate blockfile cursor for the assumedvalid
chainstate when one is in use.
Use the expected AssumeutxoData in order to bootstrap nChainTx values
for assumedvalid blockindex entries in the snapshot chainstate. This
is necessary because nChainTx is normally built up from nTx values,
which are populated using blockdata which the snapshot chainstate
does not yet have.
Introduces ChainstateManager::GetPruneRange().
The prune budget is split evenly between the number of chainstates,
however the prune budget may be exceeded if the resulting shares are
beneath `MIN_DISK_SPACE_FOR_BLOCK_FILES`.
d8041d4e04 blockstorage: Return on fatal undo file flush error (TheCharlatan)
f0207e0030 blockstorage: Return on fatal block file flush error (TheCharlatan)
5671c15f45 blockstorage: Mark FindBlockPos as nodiscard (TheCharlatan)
Pull request description:
The goal of this PR is to establish that fatal blockstorage flush errors should be treated as errors at their call site.
Prior to this patch `FlushBlockFile` may have failed without returning in `Chainstate::FlushStateToDisk`, leading to a potential write from `WriteBlockIndexDB` that may refer to a block that is not fully flushed to disk yet. By returning if either `FlushUndoFile` or `FlushBlockFile` fail, we ensure that no further write operations take place that may lead to an inconsistent database when crashing. Add `[[nodiscard]]` annotations to them such that they are not ignored in future.
Functions that call either `FlushUndoFile` or `FlushBlockFile`, need to handle these extra abort cases properly. Since `Chainstate::FlushStateToDisk` already produces an abort error in case of `WriteBlockIndexDB` failing, no extra logic for functions calling `Chainstate::FlushStateToDisk` is required.
Besides `Chainstate::FlushStateToDisk`, `FlushBlockFile` is also called by `FindBlockPos`, while `FlushUndoFile` is only called by `FlushBlockFile` and `WriteUndoDataForBlock`. For both these cases, the flush error is not further bubbled up. Instead, the error is logged and a comment is provided why bubbling up an error would be less desirable in these cases.
---
This pull request is part of a larger effort towards improving the shutdown / abort / fatal error handling in validation code. It is a first step towards implementing proper fatal error return type enforcement similar as proposed by theuni in this pull request [comment](https://github.com/bitcoin/bitcoin/pull/27711#issuecomment-1563561502). For ease of review of these critical changes, a first step would be checking that `AbortNode` leads to early and error-conveying returns at its call site. Further work for enforcing returns when `AbortNode` is called is done in https://github.com/bitcoin/bitcoin/pull/27862.
ACKs for top commit:
stickies-v:
re-ACK d8041d4
ryanofsky:
Code review ACK d8041d4e04
Tree-SHA512: 47ade9b873b15e567c8f60ca538d5a0daf32163e1031be3212a3a45eb492b866664b225f2787c9e40f3e0c089140157d8fd1039abc00c7bdfeec1b52ecd7e219
The protocol.h file contains many non-consensus related definitions and
should thus not be part of the libbitcoinkernel. This commit makes
protocol.h no longer a required include for users of the
libbitcoinkernel.
This commit is part of the libbitcoinkernel project, namely its stage 1
step 3: Decouple most non-consensus headers from libbitcoinkernel.
Co-Authored-By: Cory Fields <cory-nospam-@coryfields.com>
fae405556d scripted-diff: Rename CBlockTreeDB -> BlockTreeDB (MarcoFalke)
faf63039cc Fixup style of moved code (MarcoFalke)
fa65111b99 move-only: Move CBlockTreeDB to node/blockstorage (MarcoFalke)
fa8685597e index: Drop legacy -txindex check (MarcoFalke)
fa69148a0a scripted-diff: Use blocks_path where possible (MarcoFalke)
Pull request description:
The only reason for the check was to print a warning about an increase in storage use. Now that 22.x is EOL and everyone should have migrated (or decided to not care about storage use), remove the check.
Also, a move-only commit is included. (Rebased from https://github.com/bitcoin/bitcoin/pull/22242)
ACKs for top commit:
TheCharlatan:
ACK fae405556d, though I lack historical context to really judge the second commit fa8685597e.
stickies-v:
ACK fae405556d
Tree-SHA512: 9da8f48767ae52d8e8e21c09a40c949cc0838794f1856cc5f58a91acd3f00a3bca818c8082242b3fdc9ca5badb09059570bb3870850d3807b75a8e23b5222da1
By returning an error code if either `FlushUndoFile` or `FlushBlockFile`
fail, the caller now has to explicitly handle block undo file flushing
errors. Before this change such errors were non-explicitly ignored
without a clear rationale.
Besides the call to `FlushUndoFile` in `FlushBlockFile`, ignore its
return code at its call site in `WriteUndoDataForBlock`. There, a failed
flush of the undo data should not be indicative of a failed write.
Add [[nodiscard]] annotations to `FlushUndoFile` such that its return
value is not just ignored in the future.
By returning an error code if `FlushBlockFile` fails, the caller now has
to explicitly handle block file flushing errors. Before this change
such errors were non-explicitly ignored without a clear rationale.
Prior to this patch `FlushBlockFile` may have failed silently in
`Chainstate::FlushStateToDisk`. Improve this with a log line. Also add a
TODO comment to flesh out whether returning early in the case of an
error is appropriate or not. Returning early might be appropriate to
prohibit `WriteBlockIndexDB` from writing a block index entry that does
not refer to a fully flushed block.
Besides `Chainstate::FlushStateToDisk`, `FlushBlockFile` is also called
by `FindBlockPos`. Don't change the abort behavior there, since we don't
want to fail the function if the flushing of already written blocks
fails. Instead, just document it.
A false return value indicates a fatal error (disk space being too low),
so make sure we always consume this error code.
This commit is part of an ongoing process for making the handling of
fatal errors more transparent and easier to understand.
fa69e3a95c Remove unused MessageStartChars parameters from BlockManager methods (MarcoFalke)
Pull request description:
Seems odd to expose these for mocking, when it is not needed.
Fix this by removing the the unused parameters and use the already existing member field instead.
ACKs for top commit:
Empact:
utACK fa69e3a95c
dergoegge:
utACK fa69e3a95c
Tree-SHA512: 7814e9560abba8d9c0926bcffc70f92e502d22f543af43671248f6fcd1433f35238553c0f05123fde6d8e0f80261af0ab0500927548115153bd68d57fe2da746
The block index (CBlockTreeDB) is required to write and read blocks, so
move it to blockstorage. This allows to drop the txdb.h include from
`node/blockstorage.h`.
Can be reviewed with:
--color-moved=dimmed-zebra --color-moved-ws=ignore-all-space
When writing a new block to disk, if we have filled up the current block file,
then we flush and truncate that block file (to free allocated but unused
space) before advancing to the next one. When this happens, we have to
determine whether to also flush and truncate the corresponding undo file.
Undo data is only written when blocks are connected, not when blocks are
received. Thus it's possible that the corresponding undo file already has all
the data it will ever have, and we should flush/truncate it as we advance
files; or it's possible that there is more data we expect to write, and should
therefore defer flush/truncation until undo data is later written.
Prior to this commit, we made the determination of whether the undo file was
full of all requisite data by comparing against the chain tip. This patch
replaces that dependence on validation data structures by instead just tracking
the highest height of any block written in the undo file as we go.
This has the benefit of moving the StartShutdown call out of the
blockstorage file and thus out of the kernel's responsibility. The user
can now decide if he wants to start shutdown / interrupt after a block
import or not.
At present, during init, we traverse the chain (once per index)
to confirm that all necessary blocks to sync each index up to
the current tip are present.
To make the process more efficient, we can fetch the oldest block
from the indexers and perform the chain data existence check from
that point only once.
This also moves the pruning violation check to the end of the
'loadinit' thread, which is where the reindex, block loading and
chain activation processes happen.
Making the node's startup process faster, allowing us to remove
the global g_indexes_ready_to_sync flag, and enabling the
execution of the pruning violation verification even when the
reindex or reindex-chainstate flags are enabled (which has being
skipped so far).
By generalizing 'GetFirstStoredBlock' and implementing
'CheckBlockDataAvailability' we can dedup code and
avoid repeating work when multiple indexes are enabled.
E.g. get the oldest block across all indexes and
perform the pruning violation check from that point
up to the tip only once (this feature is being introduced
in a follow-up commit).
This commit shouldn't change behavior in any way.
Co-authored-by: Ryan Ofsky <ryan@ofsky.org>
And transfer the responsibility of verifying whether 'start_block'
has data or not to the caller.
This is because the 'GetFirstStoredBlock' function responsibility
is to return the first block containing data. And the current
implementation can return 'start_block' when it has no data!. Which
is misleading at least.
Edge case behavior change:
Previously, if the block tip lacked data but all preceding blocks
contained data, there was no prune violation. And now, such
scenario will result in a prune violation.
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-
The mempool load can take a while, and it is not
needed for the indexes' synchronization.
Also, having the mempool load function call
inside 'blockstorage.cpp' wasn't structurally
correct.
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 is achieved by letting the index sync thread wait until
reindex-chainstate is finished.
This also disables the pruning check when reindexing the chainstate (which is
incompatible with prune mode) because there would be no chain at this point
in init.
Add a stop_after_block_import field to the BlockManager options. Use
this field instead of the global gArgs.
This should allow users of the BlockManager to not rely on the global
Args.
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.
3141eab9c6 test: add functional test for ScanAndUnlinkAlreadyPrunedFiles (Andrew Toth)
e252909e56 test: add unit test for ScanAndUnlinkAlreadyPrunedFiles (Andrew Toth)
77557dda4a prune: scan and unlink already pruned block files on startup (Andrew Toth)
Pull request description:
There are a few cases where we can mark a block and undo file as pruned in our block index, but not actually remove the files from disk.
1. If we call `FindFilesToPrune` or `FindFilesToPruneManual` and crash before `UnlinkPrunedFiles`.
2. If on Windows there is an open file handle to the file somewhere else when calling `fs::remove` in `UnlinkPrunedFiles` (https://en.cppreference.com/w/cpp/filesystem/remove, https://learn.microsoft.com/en-us/windows/win32/api/fileapi/nf-fileapi-deletefilew#remarks). This could be from another process, or if we are calling `ReadBlockFromDisk`/`ReadRawBlockFromDisk` without having a lock on `cs_main` (which has been allowed since ccd8ef65f9).
This PR mitigates this by scanning all pruned block files on startup after `LoadBlockIndexDB` and unlinking them again.
ACKs for top commit:
achow101:
ACK 3141eab9c6
pablomartin4btc:
re-ACK with added functional test 3141eab9c6.
furszy:
Code review ACK 3141eab9
theStack:
Code-review ACK 3141eab9c6
Tree-SHA512: 6c73bc57838ad1b7e5d441af3c4d6bf4c61c4382e2b86485e57fbb74a61240710c0ceeceb8b4834e610ecfa3175c6955c81ea4b2285fee11ca6383f472979d8d
bcb0cacac2 reindex, log, test: fixes #21379 (mruddy)
Pull request description:
Fixes #21379.
The blocks/blk?????.dat files are mutated and become increasingly malformed, or corrupt, as a result of running the re-indexing process.
The mutations occur after the re-indexing process has finished, as new blocks are appended, but are a result of a re-indexing process miscalculation that lingers in the block manager's `m_blockfile_info` `nSize` data until node restart.
These additions to the blk files are non-fatal, but also not desirable.
That is, this is a form of data corruption that the reading code is lenient enough to process (it skips the extra bytes), but it adds some scary looking log messages as it encounters them.
The summary of the problem is that the re-index process double counts the size of the serialization header (magic message start bytes [4 bytes] + length [4 bytes] = 8 bytes) while calculating the blk data file size (both values already account for the serialization header's size, hence why it is over accounted).
This bug manifests itself in a few different ways, after re-indexing, when a new block from a peer is processed:
1. If the new block will not fit into the last blk file processed while re-indexing, while remaining under the 128MiB limit, then the blk file is flushed to disk and truncated to a size that is 8 greater than it should be. The truncation adds zero bytes (see `FlatFileSeq::Flush` and `TruncateFile`).
1. If the last blk file processed while re-indexing has logical space for the new block under the 128 MiB limit:
1. If the blk file was not already large enough to hold the new block, then the zeros are, in effect, added by `fseek` when the file is opened for writing. Eight zero bytes are added to the end of the last blk file just before the new block is written. This happens because the write offset is 8 too great due to the miscalculation. The result is 8 zero bytes between the end of the last block and the beginning of the next block's magic + length + block.
1. If the blk file was already large enough to hold the new block, then the current existing file contents remain in the 8 byte gap between the end of the last block and the beginning of the next block's magic + length + block. Commonly, when this occcurs, it is due to the blk file containing blocks that are not connected to the block tree during reindex and are thus left behind by the reindex process and later overwritten when new blocks are added. The orphaned blocks can be valid blocks, but due to the nature of concurrent block download, the parent may not have been retrieved and written by the time the node was previously shutdown.
ACKs for top commit:
LarryRuane:
tested code-review ACK bcb0cacac2
ryanofsky:
Code review ACK bcb0cacac2. This is a disturbing bug with an easy fix which seems well-worth merging.
mzumsande:
ACK bcb0cacac2 (reviewed code and did some testing, I agree that it fixes the bug).
w0xlt:
tACK bcb0cacac2
Tree-SHA512: acc97927ea712916506772550451136b0f1e5404e92df24cc05e405bb09eb6fe7c3011af3dd34a7723c3db17fda657ae85fa314387e43833791e9169c0febe51
Also:
1. Have CChainState::LoadMempool and ::ThreadImport take in paths and
pass it through untouched to LoadMempool.
2. Make LoadMempool exit early if the load_path is empty.
3. Adjust the call to ::ThreadImport in ::AppInitMain to correctly pass
in an empty path if mempool persistence is disabled.
