rpc: make gettxoutsettinfo run lock-free#6290
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For leveldb "An iterator operates on a snapshot of the database taken when the iterator is created". This means that it is unnecessary to lock out other threads while computing statistics, and neither to hold cs_main for the whole time. Let the thread run free.
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Untested ACK |
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ut ACK |
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This would mean that But i agree that we should do more of these LOCK space reducing. |
Whoa. Good catch. I expected that this would invoke CCoinsViewDB::GetBestBlock() which accesses just the db and not any internal fields or global state. But it's a virtual. It shouldn't actually be using the cached value at all but query the db. |
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Correction: CCoinsViewCache does not derive from CCoinsViewDB (or the other way around), it just wraps one. So there is no problem AFAIK. |
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Right. Was following the wrong path... it calls |
57092ed rpc: make `gettxoutsettinfo` run lock-free (Wladimir J. van der Laan)
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Couldn't nHeight change before we get to this block, after we start getting the other stats?
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Bitcoin 0.12 RPC PRs 1 Cherry-picked from the following upstream PRs: - bitcoin/bitcoin#6266 - bitcoin/bitcoin#6257 - bitcoin/bitcoin#6271 - bitcoin/bitcoin#6158 - bitcoin/bitcoin#6307 - bitcoin/bitcoin#6290 - bitcoin/bitcoin#6262 - bitcoin/bitcoin#6088 - bitcoin/bitcoin#6339 - bitcoin/bitcoin#6299 (partial, remainder in #2099) - bitcoin/bitcoin#6350 - bitcoin/bitcoin#6247 - bitcoin/bitcoin#6362 - bitcoin/bitcoin#5486 - bitcoin/bitcoin#6417 - bitcoin/bitcoin#6398 (partial, remainder was included in #1950) - bitcoin/bitcoin#6444 - bitcoin/bitcoin#6456 (partial, remainder was included in #2082) - bitcoin/bitcoin#6380 - bitcoin/bitcoin#6970 Part of #2074.
82f9088 Refactor: Remove using namespace <xxx> from /dbwrapper_tests (random-zebra) 6db0b37 rpc: make `gettxoutsettinfo` run lock-free (random-zebra) f009cf4 Do not shadow members in dbwrapper (random-zebra) b7e540c dbwrapper: Move `HandleError` to `dbwrapper_private` (random-zebra) 43004d0 leveldbwrapper file rename to dbwrapper.* (random-zebra) c882dd9 leveldbwrapper symbol rename: Remove "Level" from class, etc. names (random-zebra) f6496da leveldbwrapper: Remove unused .Prev(), .SeekToLast() methods (random-zebra) cacf3c2 Fix chainstate serialized_size computation (random-zebra) a2a3d33 Add tests for CLevelDBBatch, CLevelDBIterator (random-zebra) 94150ac Encapsulate CLevelDB iterators cleanly (random-zebra) 21df7cc [DB] Refactor leveldbwrapper (random-zebra) 2251db3 change hardcoded character constants to a set of descriptive named co… (random-zebra) Pull request description: This backports a series of updates and cleanups to the LevelDB wrapper from: - bitcoin#5707 - bitcoin#6650 [`*`] - bitcoin#6777 [`*`] - bitcoin#6865 - bitcoin#6873 - bitcoin#7927 [`*`] - bitcoin#8467 - bitcoin#6290 - bitcoin#9281 PIVX-specific edits were required to keep the sporks and zerocoin databases in line. [`*`] NOTE: excluding the obfuscation of databases by xoring data, as we might not want this feature (e.g. as zcash/zcash#2598). Otherwise it can be discussed, and added, with a separate PR. ACKs for top commit: furszy: Re ACK 82f9088 . Fuzzbawls: ACK 82f9088 Tree-SHA512: 1e4a75621d2ec2eb68e01523d15321d1d2176b81aac0525617852899ab38c9b4980daecb9056d054e7961fc758a22143edf914c40d1819144a394f2869a8ad57
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For leveldb "An iterator operates on a snapshot of the database taken when the iterator is created". This means that it is unnecessary to lock out other threads while computing statistics, and neither to hold cs_main for the whole time. Let the thread run free.
I've been using this patch for about 8 months without issues, including on a node that automatically dumps the information for every N blocks.