- Lock the mempool when removing transactions during a notification as
intended
- When generating the inventory vectors to serve on a mempool request,
recheck the memory pool for each hash since it's possible another thread
could have removed an entry after the initial query for available
hashes
- When a block is connected, remove any transactions which are now double
spends as a result of the newly connected transactions
This commit modifies the transaction memory pool handling so that it does
not relay resurrected transactions. The other peers on the network will
also be reorganizing to the same block, so they already know about them.
This change allows wallet to record all transactions in a block before
receving the new block notification, and then process them all
together when the blockconnected notification arrives.
This commit updates btcd to work with the new btcchain APIs which now
accept btcutil.Tx instead of raw btcwire.MsgTx. It also modifies the
transaction memory pool to store btcutil.Tx.
This is part of the ongoing transaction hash optimization effort noted in
conformal/btcd#25.
This change allows btcwallet to keep a pool of transactions that have
not yet been mined into a block, notifying wallet when transactions
are mined, as well as introducing a new way to send the
btcd:blockconnected notification with wallet-specific information as
part of the same notification. When a transaction is sent using the
RPC call 'sendrawtransaction', a notification request will be
automatically registered with the connected wallet (if using
websockets) to notify the wallet when the transaction first appears in
a block.
To perform this notification, and to avoid requiring wallets from
waiting for seperate mined tx notifications (and resend after a
timeout) or from sending an additional tx mined request for every tx
in the pool after each new block, the blockconnected notification is
now created seperately for each wallet. If the notified wallet has
sent a transaction, an additional JSON field "minedtxs" will include
an array of transaction IDs that the wallet has created and which are
included in the new block.
This new unique blockconnected notification can also be used for
additional notifications that may happen each new block in the future,
and to cut down on existing notification handlers in btcwallet, such
as for transactions to a watched address.
If we don't hear from a peer for 5 minutes, we disconnect them. To keep
traffic flowing we send a ping every 2 minutes if we have not send any
other message that should get a reply.
This change adds additional http listeners for websocket connections
on "/wallet". Websockets are used to provide asynchronous messaging
between wallet daemons (i.e. btcwallet) and btcd as they allow an easy
way for btcd to provide instant notifications (instead of a wallet
polling for updates) and multiple replies to a single request.
Standard RPC commands sent over a websocket connection are handled
just like RPC, returning the same results, the only difference being
that the connection is async. In cases where the standard RPC
commands fall short of wallet daemons requests, and to request
notifications for addresses and events, extension JSON methods are
used.
Multiple wallets can be connected to the same btcd, and replies to
websocket requests and notifications are properly routed back to the
original requesting wallet.
Due to the nature of turning a synchronous protocol asynchronous, it
is highly recommended to use the JSON id field as a type of sequence
number, so replies from btcd can be routed back to the proper handler
in a wallet daemon.
This commit adds code to properly respond to getdata requests for
transactions by fetching them from the transaction pool. Previously, we
advertised newly available transactions, but the code to respond with the
actual transaction was not written yet.
Also, fix a couple of comments and make the pushTxMsg and pushBlockMsg
functions consistent.
This commit is a first pass at improving the logging. It changes a number
of things to improve the readability of the output. The biggest addition
is message summaries for each message type when using the debug logging
level.
There is sitll more to do here such as allowing the level of each
subsystem to be independently specified, syslog support, and allowing the
logging level to be changed run-time.
This commit provides a new flag, --nocheckpoints, to disable built-in
checkpoints.
Checkpoints are used for a number of things such a ensuring
the block chain being downloaded matches various known good blocks,
allowing quicker verification on old blocks since scripts don't have to be
executed, and preventing forks from old blocks, etc.
The block manager handles inventory messges to know which inventory should
be requested based on what is already known and what is already in flight.
So, this commit adds logic to ask the transaction memory pool if the
transaction is already known before requesting it and tracks pending
requests into an in-flight transaction map owned by the block manager.
It also moves the transaction processing into the block manager so the
in-flight map can be properly cleaned.
Also, the loops which only remove a single element and break or return
don't need the extra logic for iteration since they don't continue
iteration after removal.
It is not safe to remove an item from a container/list while iterating the
list without first saving the next pointer since removing the item nils
the internal list element's next pointer.
Rather than showing all errors from ProcessBlock as a failure, check if
the error is a RuleError meaning the block was rejected as opposed to
something actually going wrong and log it accordingly.
This commit is a rather large one which implements transaction pool and
relay according to the protocol rules of the reference implementation.
It makes use of btcchain to ensure the transactions are valid for the
block chain and includes several stricter checks which determine if they
are "standard" or not before admitting them into the pool and relaying
them.
There are still a few TODOs around the more strict rules which determine
which transactions are willing to be mined, but the core checks which
are imperative (everything except the all of the "standard" checks really)
to operate as a good citizen on the bitcoin network are in place.
We originally wanted to also not fetch orphan parents in this commit, however,
I have discovered that if you are doing a main sync from a peer, if it
sends you an orphan you must fetch it, else you ahven't fetched
everything it told you about and thus it will nto send you end more invs
from the main sync.
So we always fetch orphan parents, but we still don't fetch from
non-sync peers (all invs from them will be unsolicited). Seems to fix some hangs
with multiple peers.
The "official" regression test tool intentionally sends some unrequested
duplicate blocks to ensure the chain handling code does not fail when
trying to insert them. This commit adds an exception to the block manager
which typically disconnects peers that send unrequested blocks (they are
misbehaving if they do this) for regression test mode.
Really, it would be nice to pass an interface{} into chain to be given
to us when the callback calls, it would avoid the awkward sidchanneling
through the map and should actually be more efffieint (pointer passing >
hashtable insert, lookup, then remove).
Rather than having all of the various places that print peer figure out
the direction and form the string, centralize it by implementing the
Stringer interface on the peer.
Chain is not concurrency safe, so we move the chainNotifySink handling
into the main blockmanager goroutine. Due to a possible deadlock if the
buffer is filled this still has to be a single channel that isn't linked
to the other ones. There is a possible starvation issue where the main
msgChan gets selected more often than the notification sink, but until
chain is concurrency safe this is rather unavoidable.
Only log errors for most cases if the peer is persisent (and thus requested).
Only log by default after version exchange, and after losing a peer that had
completed version exchange. Make most other messages debug.
Use this information so that we do not request a block per peer we got
an inv for it, makes multi peer much quieter and rather more bandwidth
efficient.
In order to remove a number of possible races we combine blockhandling
an synchandler and use one channel for all messages. This ensures that
all messages from a single peer will be recieved in order. It also
removes the need for a lot of locking between the peer removal code and
the block/inv handlers.
Previously a new goroutine was launched for each notification in order to
avoid blocking chain from continuing while the notification is being
processed. This approach had a couple of issues.
First, since goroutines are not guaranteed to execute in any given order,
the notifications were no longer handled in the same order as they were
sent. For the current code, this is not a problem, but upcoming code that
handles a transaction memory pool, the order needs to be correct.
Second, goroutines are relatively cheap, but it's still quite a bit of
overhead to launch 3-4 goroutines per block.
This commit modifies the handling code to have a single sink executing in
a separate goroutine. The main handler then adds the notifications to a
queue which is processed by the sink. This approach retains the
non-blocking behavior of the previous approach, but also keeps the order
correct and, as an additional benefit, is also more efficient.
This removes a horrible case of reach-around from per into the guts of
the blockmaanger to frob the chain. Soon, when we try to deduplicate the
fetching of blocks from multiple peers this will need decisions made in
a central point.
Discussed at length with davec.
