From e9460eb35816a98deca882e5c79d0bb314b64d93 Mon Sep 17 00:00:00 2001 From: Ryan Staudt Date: Fri, 18 Dec 2020 16:08:43 -0600 Subject: [PATCH] multi: Rework utxoset/view to use outpoints. This modifies the utxoset in the database and related UtxoViewpoint to store and work with unspent transaction outputs on a per-output basis instead of at a transaction level. The primary motivation is to simplify the code, pave the way for a utxo cache, and generally focus on optimizing runtime performance. The tradeoff is that this approach does somewhat increase the size of the serialized utxoset since it means that the transaction hash is duplicated for each output as a part of the key and some additional details are duplicated in each output. The details duplicated in each output include flags encoded into a single byte that specify whether the containing transaction is a coinbase, whether the containing transaction has an expiry, and the transaction type. Additionally, the containing block height and index are stored in each output. However, in practice, the size difference isn't all that large, disk space is relatively cheap, certainly cheaper than memory, and it is much more important to provide more efficient runtime operation since that is the ultimate purpose of the daemon. While performing this conversion, it also simplifies the code to remove the transaction version information from the utxoset as well as the spend journal. The logic for only serializing it under certain circumstances is complicated, and it was only used for the gettxout RPC, where it has already been removed. The utxo set and spend journal in the database are automatically migrated to the new format with this commit and it is possible to interrupt and resume the migration process. Finally, it also updates all references and tests that previously dealt with transaction hashes to use outpoints instead. An overview of the changes are as follows: - Remove transaction version from both spent and unspent output entries - Update utxo serialization format to exclude the version - Update spend journal serialization format to exclude the version - Convert UtxoEntry to represent a specific utxo instead of a transaction with all remaining utxos - Optimize for memory usage with an eye toward a utxo cache - Combine fields such as whether the containing transaction is a coinbase, whether the containing transaction has an expiry, and the transaction type into a single byte - Align entry fields to eliminate extra padding since ultimately there will be a lot of these in memory - Introduce a free list for serializing an outpoint to the database key format to significantly reduce pressure on the GC - Update entries to be keyed by a outpoint rather than just a tx hash - Update all related functions that previously dealt with transaction hashes to accept outpoints instead - Update all callers accordingly - Only add individually requested outputs from the mempool when constructing a mempool view - Modify the spend journal to always store the encoded flags with every spent txout - Combine fields such as whether the containing transaction is a coinbase, whether the containing transaction has an expiry, and the transaction type into a single byte - Use 4 bits instead of 3 for the transaction type to be consistent with utxos. The extra bit was already unused so this doesn't take any additional space - Remove the fully spent flag - Introduce ticketMinOuts in place of stakeExtra - Renamed stakeExtra as ticketMinOuts and updated all comments to make the purpose of the field clearer - Only store ticketMinOuts for ticket submission outputs - Add TicketMinimalOutputs function on UtxoEntry in place of ConvertUtxosToMinimalOutputs - Always decompress data loaded from the database now that a utxo entry only consists of a specific output - Introduce upgrade code to migrate the utxo set and spend journal to the new format - Update current database version to 9 - Update current utxo set version to 3 - Update current spend journal version to 3 - Introduce the ability to run upgrades after the block index has been loaded - Update all tests to expect the correct encodings, remove tests that no longer apply, and add new ones for the new expected behavior - Convert old tests for the legacy utxo format deserialization code to test the new function that is used during upgrade - Introduce a few new functions on UtxoViewpoint - AddTxOut for adding an individual txout versus all of them - addTxOut to handle the common code between the new AddTxOut and existing AddTxOuts - RemoveEntry for removing an individual txout - Remove the ErrDiscordantTxTree error - Since utxos are now retrieved using an outpoint, which includes the tree, it is no longer possible to hit this error path --- blockchain/chainio.go | 766 +++++------ blockchain/chainio_test.go | 1225 ++++++++---------- blockchain/compress.go | 146 +-- blockchain/compress_test.go | 59 +- blockchain/error.go | 5 - blockchain/error_test.go | 1 - blockchain/fullblocktests/generate.go | 2 +- blockchain/scriptval.go | 40 +- blockchain/sequencelock.go | 2 +- blockchain/stakeext.go | 15 +- blockchain/upgrade.go | 1203 ++++++++++++++++- blockchain/utxoviewpoint.go | 852 ++++++------ blockchain/utxoviewpoint_test.go | 4 +- blockchain/validate.go | 162 ++- gcs/blockcf2/blockcf.go | 4 +- internal/mempool/mempool.go | 86 +- internal/mempool/mempool_test.go | 33 +- internal/mempool/policy.go | 7 +- internal/mining/mining.go | 49 +- internal/mining/mining_harness_test.go | 73 +- internal/mining/mining_view_test.go | 3 +- internal/netsync/manager.go | 155 ++- internal/rpcserver/interface.go | 75 +- internal/rpcserver/rpcserver.go | 43 +- internal/rpcserver/rpcserverhandlers_test.go | 251 ++-- rpcadaptors.go | 24 +- server.go | 11 +- 27 files changed, 3064 insertions(+), 2232 deletions(-) diff --git a/blockchain/chainio.go b/blockchain/chainio.go index d63f26bab2..fab11e3048 100644 --- a/blockchain/chainio.go +++ b/blockchain/chainio.go @@ -12,7 +12,7 @@ import ( "errors" "fmt" "math/big" - "sort" + "sync" "time" "github.com/decred/dcrd/blockchain/stake/v4" @@ -28,7 +28,7 @@ import ( const ( // currentDatabaseVersion indicates what the current database // version is. - currentDatabaseVersion = 8 + currentDatabaseVersion = 9 // currentBlockIndexVersion indicates what the current block index // database version. @@ -74,11 +74,11 @@ var ( // spendJournalBucketName is the name of the db bucket used to house // transactions outputs that are spent in each block. - spendJournalBucketName = []byte("spendjournalv2") + spendJournalBucketName = []byte("spendjournalv3") // utxoSetBucketName is the name of the db bucket used to house the unspent // transaction output set. - utxoSetBucketName = []byte("utxosetv2") + utxoSetBucketName = []byte("utxosetv3") // blockIndexBucketName is the name of the db bucket used to house the block // index which consists of metadata for all known blocks both in the main @@ -249,15 +249,6 @@ func readDeserializeSizeOfMinimalOutputs(serialized []byte) (int, error) { return offset, nil } -// ConvertUtxosToMinimalOutputs converts the contents of a UTX to a series of -// minimal outputs. It does this so that these can be passed to stake subpackage -// functions, where they will be evaluated for correctness. -func ConvertUtxosToMinimalOutputs(entry *UtxoEntry) []*stake.MinimalOutput { - minOuts, _ := deserializeToMinimalOutputs(entry.stakeExtra) - - return minOuts -} - // ----------------------------------------------------------------------------- // The block index consists of an entry for every known block. It consists of // information such as the block header and information about votes. @@ -481,7 +472,7 @@ func dbMaybeStoreBlock(dbTx database.Tx, block *dcrutil.Block) error { // The serialized format is: // // [