The hedge middleware implements hedged requests, as described in _The
Tail At Scale_. The idea is that we auto-tune our retry logic according
to the actual network conditions, pre-emptively retrying requests that
exceed some latency percentile. This would hopefully solve the problem
where our timeouts are too long on mainnet and too slow on testnet.
Try to use the better cancellation logic to revert to previous sync
algorithm. As designed, the sync algorithm is supposed to proceed by
downloading state prospectively and handle errors by flushing the
pipeline and starting over. This hasn't worked well, because we didn't
previously cancel tasks properly. Now that we can, try to use something
in the spirit of the original sync algorithm.
This makes two changes relative to the existing download code:
1. It uses a oneshot to attempt to cancel the download task after it
has started;
2. It encapsulates the download creation and cancellation logic into a
Downloads struct.
* Reverse displayed endianness of transaction and block hashes
* fix zebra-checkpoints utility for new hash order
* Stop using "zebrad revhex" in zebrad-hash-lookup
* Rebuild checkpoint lists in new hash order
This change also adds additional checkpoints to the end of each list.
* Replace TransactionHash with transaction::Hash
This change should have been made in #905, but we missed Debug impls
and some docs.
Co-authored-by: Ramana Venkata <vramana@users.noreply.github.com>
Co-authored-by: teor <teor@riseup.net>
This reduces the API surface to the minimum required for functionality,
and cleans up module documentation. The stub mempool module is deleted
entirely, since it will need to be redone later anyways.
* implement most of the chain functions
* implement fork
* fix outpoint handling in Chain struct
* update expect for work
* split utxo into two sets
* update the Chain definition
* remove allow attribute in zebra-state/lib.rs
* merge ChainSet type into MemoryState
* Add error messages to asserts
* export proptest impls for use in downstream crates
* add testjob for disabled feature in zebra-chain
* try to fix github actions syntax
* add module doc comment
* update RFC for utxos
* add missing header
* working proptest for Chain
* propagate back results over channel
* Start updating RFC to match changes
* implement queued block pruning
* and now it syncs wooo!
* remove empty modules
* setup config for proptests
* re-enable missing_docs lint
* update RFC to match changes in impl
* add documentation
* use more explicit variable names
The Inbound service only needs the network setup for some requests, but
it can service other requests without it. Making it return
Poll::Pending until the network setup finishes means that initial
network connections may view the Inbound service as overloaded and
attempt to load-shed.
The original version of this commit ran into
https://github.com/rust-lang/rust/issues/64552
again. Thanks to @yaahc for suggesting a workaround (using futures combinators
to avoid writing an async block).
Remove the seed command entirely, and make the behavior it provided
(responding to `Request::Peers`) part of the ordinary functioning of the
start command.
The new `Inbound` service should be expanded to handle all request
types.
* add test for first checkpoint sync
Prior this this change we've not had any tests that verify our sync /
network logic is well behaved. This PR cleans up the test helper code to
make error reports more consistent and uses this cleaned up API to
implement a checkpoint sync test which runs zebrad until it reads the
first checkpoint event from stdout.
Co-authored-by: teor <teor@riseup.net>
* move include out of unix cfg
Co-authored-by: teor <teor@riseup.net>
* increase the EWMA default and decay
* increase the block download retries
* increase the request and block download timeouts
* increase the sync timeout
* add metrics and tracking endpoint tests
* test endpoints more
* add change filter test for tracing
* add await to post
* separate metrics and tracing tests
* Apply suggestions from code review
Co-authored-by: teor <teor@riseup.net>
Co-authored-by: teor <teor@riseup.net>
* Ignore sync errors when the block is already verified
If we get an error for a block that is already in our state, we don't
need to restart the sync. It was probably a duplicate download.
Also:
Process any ready tasks before reset, so the logs and metrics are
up to date. (But ignore the errors, because we're about to reset.)
Improve sync logging and metrics during the download and verify task.
* Remove duplicate hashes in logs
Co-authored-by: Jane Lusby <jlusby42@gmail.com>
* Log the sync hash span at warn level
Co-authored-by: Jane Lusby <jlusby42@gmail.com>