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Stable release v32.1bitcoin/bitcoin · f0de87f04062 ↗3,020 source files · 47.5 MB stored on the server440 file guides

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1Bitcoin Core version 0.11.0 is now available from:
2
3  <https://bitcoin.org/bin/bitcoin-core-0.11.0/>
4
5This is a new major version release, bringing both new features and
6bug fixes.
7
8Please report bugs using the issue tracker at github:
9
10  <https://github.com/bitcoin/bitcoin/issues>
11
12Upgrading and downgrading
13=========================
14
15How to Upgrade
16--------------
17
18If you are running an older version, shut it down. Wait until it has completely
19shut down (which might take a few minutes for older versions), then run the
20installer (on Windows) or just copy over /Applications/Bitcoin-Qt (on Mac) or
21bitcoind/bitcoin-qt (on Linux).
22
23Downgrade warning
24------------------
25
26Because release 0.10.0 and later makes use of headers-first synchronization and
27parallel block download (see further), the block files and databases are not
28backwards-compatible with pre-0.10 versions of Bitcoin Core or other software:
29
30* Blocks will be stored on disk out of order (in the order they are
31received, really), which makes it incompatible with some tools or
32other programs. Reindexing using earlier versions will also not work
33anymore as a result of this.
34
35* The block index database will now hold headers for which no block is
36stored on disk, which earlier versions won't support.
37
38If you want to be able to downgrade smoothly, make a backup of your entire data
39directory. Without this your node will need start syncing (or importing from
40bootstrap.dat) anew afterwards. It is possible that the data from a completely
41synchronised 0.10 node may be usable in older versions as-is, but this is not
42supported and may break as soon as the older version attempts to reindex.
43
44This does not affect wallet forward or backward compatibility. There are no
45known problems when downgrading from 0.11.x to 0.10.x.
46
47Important information
48======================
49
50Transaction flooding
51---------------------
52
53At the time of this release, the P2P network is being flooded with low-fee
54transactions. This causes a ballooning of the mempool size.
55
56If this growth of the mempool causes problematic memory use on your node, it is
57possible to change a few configuration options to work around this. The growth
58of the mempool can be monitored with the RPC command `getmempoolinfo`.
59
60One is to increase the minimum transaction relay fee `minrelaytxfee`, which
61defaults to 0.00001. This will cause transactions with fewer BTC/kB fee to be
62rejected, and thus fewer transactions entering the mempool.
63
64The other is to restrict the relaying of free transactions with
65`limitfreerelay`. This option sets the number of kB/minute at which
66free transactions (with enough priority) will be accepted. It defaults to 15.
67Reducing this number reduces the speed at which the mempool can grow due
68to free transactions.
69
70For example, add the following to `bitcoin.conf`:
71
72    minrelaytxfee=0.00005 
73    limitfreerelay=5
74
75More robust solutions are being worked on for a follow-up release.
76
77Notable changes
78===============
79
80Block file pruning
81----------------------
82
83This release supports running a fully validating node without maintaining a copy 
84of the raw block and undo data on disk. To recap, there are four types of data 
85related to the blockchain in the bitcoin system: the raw blocks as received over 
86the network (blk???.dat), the undo data (rev???.dat), the block index and the 
87UTXO set (both LevelDB databases). The databases are built from the raw data.
88
89Block pruning allows Bitcoin Core to delete the raw block and undo data once 
90it's been validated and used to build the databases. At that point, the raw data 
91is used only to relay blocks to other nodes, to handle reorganizations, to look 
92up old transactions (if -txindex is enabled or via the RPC/REST interfaces), or 
93for rescanning the wallet. The block index continues to hold the metadata about 
94all blocks in the blockchain.
95
96The user specifies how much space to allot for block & undo files. The minimum 
97allowed is 550MB. Note that this is in addition to whatever is required for the 
98block index and UTXO databases. The minimum was chosen so that Bitcoin Core will 
99be able to maintain at least 288 blocks on disk (two days worth of blocks at 10 
100minutes per block). In rare instances it is possible that the amount of space 
101used will exceed the pruning target in order to keep the required last 288 
102blocks on disk.
103
104Block pruning works during initial sync in the same way as during steady state, 
105by deleting block files "as you go" whenever disk space is allocated. Thus, if 
106the user specifies 550MB, once that level is reached the program will begin 
107deleting the oldest block and undo files, while continuing to download the 
108blockchain.
109
110For now, block pruning disables block relay.  In the future, nodes with block 
111pruning will at a minimum relay "new" blocks, meaning blocks that extend their 
112active chain. 
113
114Block pruning is currently incompatible with running a wallet due to the fact 
115that block data is used for rescanning the wallet and importing keys or 
116addresses (which require a rescan.) However, running the wallet with block 
117pruning will be supported in the near future, subject to those limitations.
118
119Block pruning is also incompatible with -txindex and will automatically disable 
120it.
121
122Once you have pruned blocks, going back to unpruned state requires 
123re-downloading the entire blockchain. To do this, re-start the node with 
124-reindex. Note also that any problem that would cause a user to reindex (e.g., 
125disk corruption) will cause a pruned node to redownload the entire blockchain. 
126Finally, note that when a pruned node reindexes, it will delete any blk???.dat 
127and rev???.dat files in the data directory prior to restarting the download.
128
129To enable block pruning on the command line:
130
131- `-prune=N`: where N is the number of MB to allot for raw block & undo data.
132
133Modified RPC calls:
134
135- `getblockchaininfo` now includes whether we are in pruned mode or not.
136- `getblock` will check if the block's data has been pruned and if so, return an 
137error.
138- `getrawtransaction` will no longer be able to locate a transaction that has a 
139UTXO but where its block file has been pruned. 
140
141Pruning is disabled by default.
142
143Big endian support
144--------------------
145
146Experimental support for big-endian CPU architectures was added in this
147release. All little-endian specific code was replaced with endian-neutral
148constructs. This has been tested on at least MIPS and PPC hosts. The build
149system will automatically detect the endianness of the target.
150
151Memory usage optimization
152--------------------------
153
154There have been many changes in this release to reduce the default memory usage
155of a node, among which:
156
157- Accurate UTXO cache size accounting (#6102); this makes the option `-dbcache`
158  precise where this grossly underestimated memory usage before
159- Reduce size of per-peer data structure (#6064 and others); this increases the
160  number of connections that can be supported with the same amount of memory
161- Reduce the number of threads (#5964, #5679); lowers the amount of (esp.
162  virtual) memory needed
163
164Fee estimation changes
165----------------------
166
167This release improves the algorithm used for fee estimation.  Previously, -1
168was returned when there was insufficient data to give an estimate.  Now, -1
169will also be returned when there is no fee or priority high enough for the
170desired confirmation target. In those cases, it can help to ask for an estimate
171for a higher target number of blocks. It is not uncommon for there to be no
172fee or priority high enough to be reliably (85%) included in the next block and
173for this reason, the default for `-txconfirmtarget=n` has changed from 1 to 2.
174
175Privacy: Disable wallet transaction broadcast
176----------------------------------------------
177
178This release adds an option `-walletbroadcast=0` to prevent automatic
179transaction broadcast and rebroadcast (#5951). This option allows separating
180transaction submission from the node functionality.
181
182Making use of this, third-party scripts can be written to take care of
183transaction (re)broadcast:
184
185- Send the transaction as normal, either through RPC or the GUI
186- Retrieve the transaction data through RPC using `gettransaction` (NOT
187  `getrawtransaction`). The `hex` field of the result will contain the raw
188  hexadecimal representation of the transaction
189- The transaction can then be broadcasted through arbitrary mechanisms
190  supported by the script
191
192One such application is selective Tor usage, where the node runs on the normal
193internet but transactions are broadcasted over Tor.
194
195For an example script see [bitcoin-submittx](https://github.com/laanwj/bitcoin-submittx).
196
197Privacy: Stream isolation for Tor
198----------------------------------
199
200This release adds functionality to create a new circuit for every peer
201connection, when the software is used with Tor. The new option,
202`-proxyrandomize`, is on by default.
203
204When enabled, every outgoing connection will (potentially) go through a
205different exit node. That significantly reduces the chance to get unlucky and
206pick a single exit node that is either malicious, or widely banned from the P2P
207network. This improves connection reliability as well as privacy, especially
208for the initial connections.
209
210**Important note:** If a non-Tor SOCKS5 proxy is configured that supports
211authentication, but doesn't require it, this change may cause that proxy to reject
212connections. A user and password is sent where they weren't before. This setup
213is exceedingly rare, but in this case `-proxyrandomize=0` can be passed to
214disable the behavior.
215
2160.11.0 Change log
217=================
218
219Detailed release notes follow. This overview includes changes that affect
220behavior, not code moves, refactors and string updates. For convenience in locating
221the code changes and accompanying discussion, both the pull request and
222git merge commit are mentioned.
223
224### RPC and REST
225- #5461 `5f7279a` signrawtransaction: validate private key
226- #5444 `103f66b` Add /rest/headers/<count>/<hash>.<ext>
227- #4964 `95ecc0a` Add scriptPubKey field to validateaddress RPC call
228- #5476 `c986972` Add time offset into getpeerinfo output
229- #5540 `84eba47` Add unconfirmed and immature balances to getwalletinfo
230- #5599 `40e96a3` Get rid of the internal miner's hashmeter
231- #5711 `87ecfb0` Push down RPC locks
232- #5754 `1c4e3f9` fix getblocktemplate lock issue
233- #5756 `5d901d8` Fix getblocktemplate_proposals test by mining one block
234- #5548 `d48ce48` Add /rest/chaininfos
235- #5992 `4c4f1b4` Push down RPC reqWallet flag
236- #6036 `585b5db` Show zero value txouts in listunspent
237- #5199 `6364408` Add RPC call `gettxoutproof` to generate and verify merkle blocks
238- #5418 `16341cc` Report missing inputs in sendrawtransaction
239- #5937 `40f5e8d` show script verification errors in signrawtransaction result
240- #5420 `1fd2d39` getutxos REST command (based on Bip64)
241- #6193 `42746b0` [REST] remove json input for getutxos, limit to query max. 15 outpoints
242- #6226 `5901596` json: fail read_string if string contains trailing garbage
243
244### Configuration and command-line options
245- #5636 `a353ad4` Add option `-allowselfsignedrootcertificate` to allow self signed root certs (for testing payment requests)
246- #5900 `3e8a1f2` Add a consistency check `-checkblockindex` for the block chain data structures
247- #5951 `7efc9cf` Make it possible to disable wallet transaction broadcast (using `-walletbroadcast=0`)
248- #5911 `b6ea3bc` privacy: Stream isolation for Tor (on by default, use `-proxyrandomize=0` to disable)
249- #5863 `c271304` Add autoprune functionality (`-prune=<size>`)
250- #6153 `0bcf04f` Parameter interaction: disable upnp if -proxy set

src/wallet/receive.cpp

src/wallet/coinselection.cpp

src/consensus/validation.h

src/primitives/transaction.cpp

src/script/descriptor.cpp

src/bitcoin-cli.cpp

src/rpc/blockchain.cpp

src/rpc/rawtransaction.cpp

src/init.cpp

src/crypto/sha256.cpp

src/consensus/merkle.h

src/consensus/tx_check.h

src/consensus/tx_verify.h

src/policy/feerate.h

src/policy/feerate.cpp

src/primitives/transaction_identifier.h

src/chainparamsbase.h

src/chainparamsbase.cpp

src/util/moneystr.cpp

src/crypto/ripemd160.h

src/crypto/sha1.h

src/crypto/sha512.h

src/crypto/hmac_sha256.h

src/crypto/hmac_sha512.h

src/crypto/hmac_sha256.cpp

src/crypto/hmac_sha512.cpp

src/crypto/hkdf_sha256_32.h

src/crypto/hkdf_sha256_32.cpp

src/support/cleanse.h

src/support/cleanse.cpp

src/crypto/siphash.cpp

src/crypto/muhash.h

src/crypto/chacha20.h

src/crypto/poly1305.h

src/crypto/chacha20poly1305.h

src/crypto/chacha20poly1305.cpp

src/util/chaintype.cpp

src/util/obfuscation.h

src/util/byte_units.h

src/util/overflow.h

src/blockencodings.cpp

src/net_permissions.cpp

src/policy/packages.cpp

src/policy/rbf.cpp

src/policy/truc_policy.cpp

src/policy/ephemeral_policy.cpp

src/policy/settings.cpp

src/policy/policy.cpp

src/node/transaction.cpp

src/node/coin.cpp

src/rpc/client.cpp

src/rpc/external_signer.cpp

src/rpc/request.cpp

src/rpc/server_util.cpp

src/rpc/fees.cpp

src/rpc/output_script.cpp

src/rpc/rawtransaction_util.cpp

src/rpc/rawtransaction_util.h

src/rpc/register.h

src/rpc/request.h

src/rpc/server_util.h

src/rpc/protocol.h

src/rpc/server.h

src/rpc/signmessage.cpp

src/rpc/txoutproof.cpp

src/rpc/util.cpp

src/rpc/util.h

src/wallet/rpc/addresses.cpp

src/wallet/rpc/backup.cpp

src/wallet/rpc/coins.cpp

src/wallet/rpc/encrypt.cpp

src/wallet/rpc/signmessage.cpp

src/wallet/rpc/util.cpp

src/wallet/rpc/util.h

src/wallet/coincontrol.cpp

src/wallet/coincontrol.h

src/wallet/context.cpp

src/wallet/context.h

src/wallet/crypter.cpp

src/wallet/crypter.h

src/wallet/db.cpp

src/wallet/export.cpp

src/wallet/external_signer_scriptpubkeyman.cpp

src/wallet/rpc/spend.cpp

src/wallet/rpc/transactions.cpp

src/wallet/rpc/wallet.cpp

src/wallet/feebumper.cpp

src/wallet/feebumper.h

src/index/base.h

src/index/base.cpp

src/index/txindex.h

src/index/txindex.cpp

src/index/txindex_key.h

src/index/txospenderindex.h

src/index/txospenderindex.cpp

src/index/blockfilterindex.h

src/index/blockfilterindex.cpp

src/index/coinstatsindex.h

src/index/coinstatsindex.cpp

src/index/db_key.h

src/index/disktxpos.h

src/kernel/chain.cpp

src/kernel/chain.h

src/kernel/checks.cpp

src/kernel/checks.h

src/kernel/context.cpp

src/kernel/context.h

src/kernel/cs_main.cpp

src/kernel/cs_main.h

src/kernel/disconnected_transactions.cpp

src/kernel/disconnected_transactions.h

src/kernel/mempool_removal_reason.cpp

src/kernel/mempool_removal_reason.h

src/kernel/coinstats.cpp

src/kernel/coinstats.h

src/kernel/chainparams.cpp

src/kernel/chainparams.h

src/wallet/sqlite.cpp

src/wallet/sqlite.h

src/wallet/transaction.cpp

src/wallet/transaction.h

src/wallet/dump.cpp

src/wallet/dump.h

src/wallet/init.cpp

src/wallet/walletutil.cpp

src/wallet/walletutil.h

src/wallet/wallettool.cpp

src/wallet/wallettool.h

src/wallet/export.h

src/wallet/migrate.cpp

src/wallet/migrate.h

src/wallet/db.h

src/wallet/walletdb.cpp

src/wallet/interfaces.cpp

src/wallet/scriptpubkeyman.cpp

src/wallet/scriptpubkeyman.h

src/kernel/bitcoinkernel.cpp

src/kernel/bitcoinkernel.h

src/kernel/bitcoinkernel_wrapper.h

src/node/chainstate.cpp

src/node/chainstate.h

src/node/blockstorage.cpp

src/node/blockstorage.h

src/node/mempool_persist.cpp

src/node/mempool_persist.h

src/node/utxo_snapshot.cpp

src/node/utxo_snapshot.h

src/node/kernel_notifications.cpp

src/node/kernel_notifications.h

src/node/blockmanager_args.cpp

src/kernel/blockmanager_opts.h

src/util/expected.cpp

src/policy/settings.h

src/util/types.h

src/kernel/messagestartchars.h

src/kernel/warning.h

src/util/exception.h

src/common/license_info.h

src/node/coins_view_args.h

src/node/database_args.h

src/util/batchpriority.h

src/util/ui_change_type.h

src/node/coins_view_args.cpp

src/node/peerman_args.h

src/util/serfloat.h

src/node/blockmanager_args.h

src/node/database_args.cpp

src/util/overloaded.h

src/interfaces/types.h

src/node/chainstatemanager_args.h

src/node/minisketchwrapper.h

src/util/macros.h

src/util/syserror.h

src/common/run_command.h

src/util/bytevectorhash.cpp

src/node/mempool_persist_args.cpp

src/util/exec.h

src/util/rbf.h

src/crypto/hex_base.h

src/node/mempool_persist_args.h

src/interfaces/echo.h

src/util/any.h

src/util/batchpriority.cpp

src/util/threadnames.h

src/node/coin.h

src/node/mempool_args.h

src/util/asmap.h

src/util/bytevectorhash.h

src/node/context.cpp

src/util/insert.h

src/util/readwritefile.h

src/node/peerman_args.cpp

src/node/interface_ui.cpp

src/interfaces/handler.h

src/node/mining_args.h

src/util/hasher.cpp

src/common/init.h

src/kernel/mempool_limits.h

src/common/system.h

src/crypto/sha3.h

src/util/threadinterrupt.cpp

src/node/protocol_version.h

src/util/exception.cpp

src/common/messages.h

src/node/connection_types.cpp

src/util/bip32.h

src/common/license_info.cpp

src/util/stdmutex.h

src/common/run_command.cpp

src/util/check.cpp

src/util/golombrice.h

src/node/types.h

src/node/timeoffsets.h

src/util/readwritefile.cpp

src/util/fastrange.h

src/util/signalinterrupt.h

src/util/task_runner.h

src/util/syserror.cpp

src/common/interfaces.cpp

src/common/types.h

src/util/threadinterrupt.h

src/kernel/chainstatemanager_opts.h

src/node/psbt.h

src/policy/ephemeral_policy.h

src/util/trace.h

src/common/url.cpp

src/kernel/mempool_options.h

src/util/serfloat.cpp

src/kernel/notifications_interface.h

src/node/timeoffsets.cpp

src/node/warnings.cpp

src/util/hash_type.h

src/crypto/hex_base.cpp

src/node/eviction.h

src/util/tokenbucket.h

src/crypto/aes.h

src/common/pcp.h

src/util/feefrac.cpp

src/node/transaction.h

src/util/threadnames.cpp

src/common/signmessage.h

src/util/exec.cpp

src/util/signalinterrupt.cpp

src/clientversion.cpp

src/common/signmessage.cpp

src/compat/assumptions.h

src/compat/byteswap.h

src/deploymentinfo.cpp

src/deploymentinfo.h

src/deploymentstatus.cpp

src/deploymentstatus.h

src/dummywallet.cpp

src/external_signer.h

src/init/bitcoin-gui.cpp

src/init/bitcoin-node.cpp

src/init/bitcoin-qt.cpp

src/init/bitcoin-wallet.cpp

src/init/bitcoind.cpp

src/init/common.h

src/interfaces/init.h

src/interfaces/ipc.h

src/key_io.h

src/logging/categories.h

src/logging/timer.h

src/mapport.h

src/musig.h

src/net_permissions.h

src/netgroup.h

src/netmessagemaker.h

src/node/chainstatemanager_args.cpp

src/node/connection_types.h

src/node/context.h

src/node/interface_ui.h

src/node/mempool_args.cpp

src/node/mining_args.cpp

src/node/minisketchwrapper.cpp

src/node/txreconciliation.h

src/policy/fees/estimator_args.cpp

src/policy/fees/estimator_args.h

src/policy/fees/estimator_man.cpp

src/policy/fees/estimator_man.h

src/policy/packages.h

src/policy/rbf.h

src/policy/truc_policy.h

src/pow.h

src/primitives/block.cpp

src/randomenv.h

src/rest.h

src/script/keyorigin.h

src/script/parsing.cpp

src/script/parsing.h

src/script/script_error.h

src/script/sigcache.cpp

src/script/sigcache.h

src/script/solver.h

src/script/verify_flags.h

src/semaphore_grant.h

src/signet.h

src/span.h

src/support/allocators/secure.h

src/support/allocators/zeroafterfree.h

src/util/tokenpipe.cpp

src/util/translation.h

src/util/vector.h

src/versionbits.h

src/versionbits_impl.h

src/wallet/external_signer_scriptpubkeyman.h

src/wallet/fees.h

src/wallet/load.h

src/wallet/receive.h

src/wallet/rpc/wallet.h

src/wallet/types.h

src/walletinitinterface.h

src/zmq/zmqabstractnotifier.cpp

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