refactor: move block writes and pruning into BlockManager #36738

pull pzafonte wants to merge 8 commits into bitcoin:master from pzafonte:blockstorage-prune-bookkeeping changing 6 files +370 −168

pzafonte commented at 11:58 PM on November 2, 2026: contributor

FlushStateToDisk() handles block storage directly. It applies BlockManager's prune locks, writes its pruned flag, checks its blocks directory space and runs the flush, index write and file deletion, while BlockManager reads the chainstate to pick files. A pruning API on block storage (#35627) would have to go through validation for all of it.

This moves the storage side into BlockManager, as described in the same issue. Validation decides which heights may be pruned and passes them as limits. BlockManager applies its prune locks, selects the files, flushes, writes the index and deletes the files, in the same order as before. There is no behavior change to my knowledge.

Based on #36735

Thanks to musaHaruna for his review on my fork, which led to grouping and checking the prune limits and to moving the prune bookkeeping into BlockManager.

test: apply BlockManager args in test fixtures

Without this, -prune and -fastprune in extra_args have no effect.

24ad36d929

test: check flush retry after failure

Move the blk file aside instead of deleting it, so it can be restored.

2334d27a24

test: characterize a failed prune flush

The pruned blk/rev files are not deleted, even after a later flush
succeeds.

108d7ff03c

validation: delete pruned files on a later flush

Files selected for pruning were kept in a local, so a failed flush left
them on disk until the next startup.

Keep them in BlockManager and delete them after the next block index
write. Take them with the dirty entries, which WriteBlockIndexDB() drops
even if the write fails. Drop a file from the set once a block is
written to it.

Pending files wait for the next periodic, forced or shutdown flush
rather than forcing one, which would retry a failing write on every
block.

d224fb8721

refactor: let BlockManager write block storage

Move the block and undo file flush, block index write and pruned file
deletion from FlushStateToDisk into BlockManager. Their bench log lines
change from FlushStateToDisk to WriteBlockStorage.

fb911aecde

refactor: apply prune locks in BlockManager

Validation read BlockManager's prune locks directly. Move that code and
PRUNE_LOCK_BUFFER into BlockManager.

14de6dfdf5

refactor: pass prune limits to BlockManager

BlockManager read the chainstate to decide what to prune. Decide in
validation and pass the height range and sizes instead. An Assume checks
the heights are non-negative.

ae7d92d02e

refactor: move prune bookkeeping into BlockManager

Move FlushStateToDisk's handling of the prune request, prune locks,
pruned flag, files to delete and blocks directory space check into
BlockManager. The prune request is cleared before the prune locks are
applied rather than after selection, which differs only if selection
throws.

An Assume checks that the pruned flag is set before files are queued
for deletion, so a restart knows blocks were deleted.

777b2f90de

DrahtBot added the label Refactoring on Nov 2, 2026
DrahtBot commented at 11:58 PM on November 2, 2026: contributor


The following sections might be updated with supplementary metadata relevant to reviewers and maintainers.



External sites
- Code coverage & benchmarks: https://corecheck.dev/bitcoin/bitcoin/pulls/36738
- Ralph review <img src=https://review.fish.foo/assets/bitcoin/bitcoin/36738.png alt="Ralph review status"> https://git.fish.foo/bitcoin/bitcoin/pulls/36738#author-ralph


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Conflicts

Reviewers, this pull request conflicts with the following ones:
- #36621 <img src="https://drahtbot.space/ack_count/bitcoin/bitcoin/36621.svg"> (node: batch block file pruning in a single pass over block index by mutatrum)
- #36326 <img src="https://drahtbot.space/ack_count/bitcoin/bitcoin/36326.svg"> (kernel: Use typed errors for fatal and flush error notifications by arejula27)
- #36033 <img src="https://drahtbot.space/ack_count/bitcoin/bitcoin/36033.svg"> ([wip,nomerge,rfc] build: Require C++23 compiler by maflcko)
- #35570 <img src="https://drahtbot.space/ack_count/bitcoin/bitcoin/35570.svg"> (refactor: Change some validation.cpp methods to return BlockValidationState by optout21)
- #34534 <img src="https://drahtbot.space/ack_count/bitcoin/bitcoin/34534.svg"> (rpc: Manual prune lock management (Take 2) by fjahr)
- #31260 <img src="https://drahtbot.space/ack_count/bitcoin/bitcoin/31260.svg"> (scripted-diff: Type-safe settings retrieval by ryanofsky)
If you consider this pull request important, please also help to review the conflicting pull requests. Ideally, start with the one that should be merged first.

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pzafonte

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Labels

Refactoring

Linked (view graph)

#35627 kernel: can't work with pruned blocksdir #36735 validation: delete pruned files after a failed flush #36739 refactor: pass BlockManager to ChainstateManager

refactor: move block writes and pruning into BlockManager #36738

External sites

Reviews

Conflicts