Cherrypick recent changes to gossip RFC
Delete the RFC since this is all implemented.
See: 02bfcd23a9
This commit is contained in:
parent
c83538a60c
commit
90a0237457
|
@ -37,14 +37,12 @@ Upon receiving a push message, a node examines the message for:
|
|||
1. Duplication: if the message has been seen before, the node responds with
|
||||
`PushMessagePrune` and drops the message
|
||||
|
||||
2. New information: if the message is new the node
|
||||
|
||||
a. Stores the new information and updates its version
|
||||
|
||||
b. Stores the message in `pushed_once` (used for detecting duplicates,
|
||||
purged after `PUSH_MSG_TIMEOUT * 5` ms)
|
||||
|
||||
c. Retransmits the messages to its own push peers
|
||||
2. New data: if the message is new to the node
|
||||
* Stores the new information with an updated version in its cluster info and
|
||||
purges any previous older value
|
||||
* Stores the message in `pushed_once` (used for detecting duplicates,
|
||||
purged after `PUSH_MSG_TIMEOUT * 5` ms)
|
||||
* Retransmits the messages to its own push peers
|
||||
|
||||
3. Expiration: nodes drop push messages that are older than `PUSH_MSG_TIMEOUT`
|
||||
|
||||
|
@ -66,6 +64,16 @@ that represents things it already has. A node receiving a pull message
|
|||
iterates over its values and constructs a pull response of things that miss the
|
||||
filter and would fit in a message.
|
||||
|
||||
A node constructs the pull Bloom filter by iterating over the values it
|
||||
currently has.
|
||||
A node constructs the pull Bloom filter by iterating over current values and
|
||||
recently purged values.
|
||||
|
||||
A node handles items in a pull response the same way it handles new data in a
|
||||
push message.
|
||||
|
||||
|
||||
## Purging
|
||||
|
||||
Nodes retain prior versions of values (those updated by a pull or push) and
|
||||
expired values (those older than `GOSSIP_PULL_CRDS_TIMEOUT_MS`) in
|
||||
`purged_values` (things I recently had). Nodes purge `purged_values` that are
|
||||
older than `5 * GOSSIP_PULL_CRDS_TIMEOUT_MS`.
|
||||
|
|
|
@ -1,78 +0,0 @@
|
|||
# Gossip, A.K.A. Cluster Info
|
||||
|
||||
This RFC describes the Solana's gossip protocol, also known as the network
|
||||
control plane.
|
||||
|
||||
Nodes continuously share signed data objects among themselves in order to find
|
||||
each other, structure the network data plane, prevent censoring, etc.
|
||||
|
||||
The basic mechanism is a 10Hz loop wherein every node sends a push message
|
||||
and/or a pull message. Push and pull messages may elicit responses, and push
|
||||
messages may be forwarded on to others in the network.
|
||||
|
||||
Gossip runs on a well-known UDP/IP port, or a port in a well-known range. Once
|
||||
a network is bootstrapped, nodes advertise to each other where to find their
|
||||
gossip endpoint (a socket address).
|
||||
|
||||
## Gossip Records
|
||||
|
||||
Records shared over gossip are arbitrary, but signed and versioned (with a
|
||||
timestamp), and need to make sense to the node receiving them. A strategy of
|
||||
"most recent timestamp wins" is employed to manage what's stored in cluster
|
||||
info. If 2 values from the same creator have the same timestamp, the value
|
||||
with the greater hash wins.
|
||||
|
||||
## Push
|
||||
|
||||
### Push Message
|
||||
|
||||
A push message is "hey network, I have something new to share". Nodes send
|
||||
push messages to `PUSH_FANOUT` push peers.
|
||||
|
||||
Upon receiving a push message, a node examines the message for:
|
||||
|
||||
1. duplication: if the message has been seen before, the node responds with
|
||||
`PushMessagePrune` and drops the message
|
||||
|
||||
2. new data: if the message is new to the node
|
||||
* stores the new information with an updated version in its cluster info and
|
||||
purges any previous older value
|
||||
* stores the message in `pushed_once` (used for detecting duplicates,
|
||||
purged after `PUSH_MSG_TIMEOUT * 5` ms)
|
||||
* retransmits the messages to its own push peers
|
||||
|
||||
3. expiration: nodes drop push messages that are older than `PUSH_MSG_TIMEOUT`
|
||||
|
||||
### Push Peers, Prune Message
|
||||
|
||||
A nodes selects its push peers at random from the active set of known peers.
|
||||
The node keeps this selection for a relatively long time. When a prune message
|
||||
is received, the node drops the push peer that sent the prune. Prune is an
|
||||
indication that there is another, faster path to that node than direct push.
|
||||
|
||||
The set of push peers is kept fresh by rotating a new node into the set every
|
||||
`PUSH_MSG_TIMEOUT/2` milliseconds.
|
||||
|
||||
## Pull
|
||||
|
||||
### Pull Message
|
||||
|
||||
A pull message is "hey dude, got anything new?". A pull message is sent to a
|
||||
single peer at random and comprises a Bloom filter that represents "things I
|
||||
have or recently had". A node receiving a pull message iterates over its values
|
||||
and constructs a pull response of things that miss the filter and would fit in a
|
||||
message.
|
||||
|
||||
A node constructs the pull Bloom filter by iterating over current values and
|
||||
recently purged values.
|
||||
|
||||
A node handles items in a pull response the same way it handles new data in a
|
||||
push message.
|
||||
|
||||
|
||||
## Purging
|
||||
|
||||
Nodes retain prior versions of values (those updated by a pull or push) and
|
||||
expired values (those older than `GOSSIP_PULL_CRDS_TIMEOUT_MS`) in
|
||||
`purged_values` (things I recently had). Nodes purge `purged_values` that are
|
||||
older than `5 * GOSSIP_PULL_CRDS_TIMEOUT_MS`.
|
Loading…
Reference in New Issue