This changed the node pruning logic and moved test/functional/feature_blockfilterindex_prune.py
to test/functional/feature_index_prune.py.
Please verify that:
1. I migrated the test correctly
2. The magic numbers in the test look fine
With respect to #2: I believe the magic numbers are wrong. I previously had to tweak them heavily
in commit 1278b31. I don't think I did it correctly then, and so I don't believe them to be correct now.
To summarize what this tweaking was: I changed the magic numbers in the test to work properly,
but I suspect that in changing them, I may have nullified what the test was testing.
It's very possible that the reason the test was failing was because of an underlying bug with the pruning
in elements which we have to fix, rather than just being an issue with the test itself.
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
