mirrors/tendermint
1
0
Fork 0
mirror of https://github.com/tendermint/tendermint.git synced 2026-02-10 22:10:11 +00:00
Code Issues Packages Projects Releases Wiki Activity

add section on the event system

Browse Source
This commit is contained in:
William Banfield
2021-09-14 17:02:29 -04:00
parent 5bd3b286a2
commit d91ec36a95
2 changed files with 20 additions and 2 deletions
Download Patch File Download Diff File Expand all files Collapse all files

20
docs/rfc/rfc-003-performance-questions.md
View File

@@ -236,7 +236,21 @@ of the slowdown in the Cosmos Hub and in Tendermint consensus.
### Tendermint Event System
// TODO: (@wbanfield)
The Tendermint Event system is used to communicate and store information about
internal Tendermint execution. The system uses channels internally to send messages
to different subscribers. Sending an event [blocks on the internal channel][event-send].
The default configuration is to [use an unbuffered channel for event publishes][event-buffer-capacity].
Several consumers of the event system also use an unbuffered channel for reads.
An example of this is the [event indexer][event-indexer-unbuffered], which takes an
unbuffered subscription to the event system. The result is that these unbuffered readers
can cause writes to the event system to block or slow down depending on contention in the
event system. This has implications for the consensus system, which [publishes events][consensus-event-send].
To better understand the performance of the event system, we should add metrics to track the timing of
event sends. The following metrics would be a good start for tracking this performance:
* Time in event send, labeled by Event Type
* Time in event receive, labeled by subscriber
* Event throughput, measured in events per unit time.
### References
[modular-hashing]: https://github.com/tendermint/tendermint/pull/6773
@@ -249,3 +263,7 @@ of the slowdown in the Cosmos Hub and in Tendermint consensus.
[abci-local-client-code]: https://github.com/tendermint/tendermint/blob/511bd3eb7f037855a793a27ff4c53c12f085b570/abci/client/local_client.go#L84
[hub-signature]: https://github.com/cosmos/gaia/blob/0ecb6ed8a244d835807f1ced49217d54a9ca2070/docs/resources/genesis.md#consensus-parameters
[ed25519-bench]: https://github.com/oasisprotocol/curve25519-voi/blob/d2e7fc59fe38c18ca990c84c4186cba2cc45b1f9/PERFORMANCE.md
[event-send]: https://github.com/tendermint/tendermint/blob/5bd3b286a2b715737f6d6c33051b69061d38f8ef/libs/pubsub/pubsub.go#L338
[event-buffer-capacity]: https://github.com/tendermint/tendermint/blob/5bd3b286a2b715737f6d6c33051b69061d38f8ef/types/event_bus.go#L14
[event-indexer-unbuffered]: https://github.com/tendermint/tendermint/blob/5bd3b286a2b715737f6d6c33051b69061d38f8ef/state/indexer/indexer_service.go#L39
[consensus-event-send]: https://github.com/tendermint/tendermint/blob/5bd3b286a2b715737f6d6c33051b69061d38f8ef/internal/consensus/state.go#L1573

2
internal/consensus/state.go
View File

@@ -137,7 +137,7 @@ type State struct {
done chan struct{}
// synchronous pubsub between consensus state and reactor.
// state only emits EventNewRoundStep and EventVote
// state only emits EventNewRoundStep, EventValidBlock, and EventVote
evsw tmevents.EventSwitch
// for reporting metrics