This speeds up wallet refresh by directly retrieving a tx's amount output indices.
It removes the indirection and walking the amount output duplicate list
for every amount in each requested tx.
"tx_outputs" is used by:
Amount output indices are needed for wallet refresh.
Global output indices are needed for removing a tx.
Both amount output indices and global output indices are now stored in
an array of 64-bit unsigned ints:
tx_outputs[<tx_hash>] -> [ <a1_oi, a1_gi, a2_oi, a2_gi, ...> ]
Previously it was:
tx_outputs[<tx_hash>] -> duplicate list of <a1_gi, a2_gi, a3_gi, ...>
The amount output list had to be walked for every amount in order to
find each amount's output index, by comparing the amount's global output
index with each one in the duplicate list until a match was found.
See also d045dfa7ce
bdec7cb BlockchainLMDB: Use DB error helper consistently (warptangent)
c5932eb BlockchainLMDB: Add DB error to exception (warptangent)
a49c355 Blockchain: Omit verbose time stats messages by default (warptangent)
When keys are contiguous and monotonically increasing, this gets
denser page utilization (doesn't leave padding in page splits).
Can't be used for keys that are inserted in random order (e.g. hashes)
In total this only saves around 1.5% of space compared to original
DB code. The previous patch accounted for 0.8% savings on its own;
the blocks tables just aren't that big.
Add another DB error exception type to distinguish failed txn setup from
general use of txn.
This keeps the error handling flow the same as before the block-level
txn setup changes that moved control up a layer to BlockchainDB.
b39aae7 Tweak 45800a25e9 (hyc)
4a5a5ff blockchain: always stop the ioservice before returning (moneromooo-monero)
78b65cf db_lmdb: safety close db at exit (moneromooo-monero)
45800a2 db_lmdb: fix a strdup/delete[] mistmatch (moneromooo-monero)
79beed2 tests: fix various tests by using parameters better suited to monero (moneromooo-monero)
d0a8362 tests: fix some double spending tests (moneromooo-monero)
2358d0d tests: use 255 as a "too high" block version (moneromooo-monero)
f33a88c blockchain: fix a few block addition bugs (moneromooo-monero)
a9ff11c blockchain: fix an off by one error in unlocked time check (moneromooo-monero)
f294be3 blockchain: reinstate double spending checks in check_tx_inputs (moneromooo-monero)
737b6d6 blockchain: make some flag twiddling code closer to the original (moneromooo-monero)
81cb0fc blockchain: fix bitflipping test with quantized block rewards (moneromooo-monero)
22ddf09 blockchain: add missing m_tx_pool.on_blockchain_dec (moneromooo-monero)
d837c0c blockchain: fix switch to alternative blockchain for more than one block (moneromooo-monero)
5cec076 blockchain: add a missing validity check to rollback_blockchain_switching (moneromooo-monero)
3cabdb5 core: catch exceptions from get_output_key (moneromooo-monero)
5eef645 db: throw when given a non txout_to_key output to add (moneromooo-monero)
The check was explicit in the original version, so it seems
safer to make it explicit here, especially as it is now done
implicitely in a different place, away from the original check.
This improves blockchain reorganization time by allowing one of the more
expensive DB lookups when popping a block to not have to seek through a
long dup list in the "output_amounts" subdb. This is most noticeable for
HDDs.
As before, the dup list is still walked if necessary (but in reverse),
and the global output index still confirmed to be the one looked for.
But under proper use, the result will be found at the end of the dup
list, so we start there.
Removing an amount output index is always done in the context of popping
a block, so the global output index being looked for should be the last
one in that amount key's dup list. Even if the txs themselves aren't
removed in reverse order (supposed to be according to original
implementation), the specified amount output index will still be near
the end, because the txs are in the same block.
TEST:
Pop blocks with blockchain_import.
Blocks should be successfully removed with no errors shown.
bitmonerod should be able to start syncing from the reduced blockchain
height.
