## Problem
When Availabilities are created, the amount of bytes in the Availability are reserved in the repo, so those bytes on disk cannot be written to otherwise. When a request for storage is received by a node, if a previously created Availability is matched, an attempt will be made to fill a slot in the request (more accurately, the request's slots are added to the SlotQueue, and eventually those slots will be processed). During download, bytes that were reserved for the Availability were released (as they were written to disk). To prevent more bytes from being released than were reserved in the Availability, the Availability was marked as used during the download, so that no other requests would match the Availability, and therefore no new downloads (and byte releases) would begin. The unfortunate downside to this, is that the number of Availabilities a node has determines the download concurrency capacity. If, for example, a node creates a single Availability that covers all available disk space the operator is willing to use, that single Availability would mean that only one download could occur at a time, meaning the node could potentially miss out on storage opportunities.
## Solution
To alleviate the concurrency issue, each time a slot is processed, a Reservation is created, which takes size (aka reserved bytes) away from the Availability and stores them in the Reservation object. This can be done as many times as needed as long as there are enough bytes remaining in the Availability. Therefore, concurrent downloads are no longer limited by the number of Availabilities. Instead, they would more likely be limited to the SlotQueue's `maxWorkers`.
From a database design perspective, an Availability has zero or more Reservations.
Reservations are persisted in the RepoStore's metadata, along with Availabilities. The metadata store key path for Reservations is ` meta / sales / reservations / <availabilityId> / <reservationId>`, while Availabilities are stored one level up, eg `meta / sales / reservations / <availabilityId> `, allowing all Reservations for an Availability to be queried (this is not currently needed, but may be useful when work to restore Availability size is implemented, more on this later).
### Lifecycle
When a reservation is created, its size is deducted from the Availability, and when a reservation is deleted, any remaining size (bytes not written to disk) is returned to the Availability. If the request finishes, is cancelled (expired), or an error occurs, the Reservation is deleted (and any undownloaded bytes returned to the Availability). In addition, when the Sales module starts, any Reservations that are not actively being used in a filled slot, are deleted.
Having a Reservation persisted until after a storage request is completed, will allow for the originally set Availability size to be reclaimed once a request contract has been completed. This is a feature that is yet to be implemented, however the work in this PR is a step in the direction towards enabling this.
### Unknowns
Reservation size is determined by the `StorageAsk.slotSize`. If during download, more bytes than `slotSize` are attempted to be downloaded than this, then the Reservation update will fail, and the state machine will move to a `SaleErrored` state, deleting the Reservation. This will likely prevent the slot from being filled.
### Notes
Based on #514
* cleanup erasure coding
* moar cleanup
* fix off by 1 issues in tests
* style
* consolidate decoding data code
* simplify tuple unpacking
* fix retrieve purchase
We don't support single blocks for now
* Apply suggestions from code review
Co-authored-by: Eric <5089238+emizzle@users.noreply.github.com>
Signed-off-by: Dmitriy Ryajov <dryajov@gmail.com>
---------
Signed-off-by: Dmitriy Ryajov <dryajov@gmail.com>
Co-authored-by: Eric <5089238+emizzle@users.noreply.github.com>
* [docs] fix two client scenario: add missing collateral
* [integration] separate step to wait for node to be started
* [cli] add option to specify ethereum private key
* Remove unused imports
* Fix warnings
* [integration] move type definitions to correct place
* [integration] wait a bit longer for a node to start in debug mode
When e.g. running against Taiko test net rpc, the node start
takes longer
* [integration] simplify handling of codex node and client
* [integration] add Taiko integration test
* [contracts] await token approval confirmation before next tx
* [contracts] deployment address of marketplace on Taiko
* [cli] --eth-private-key now takes a file name
Instead of supplying the private key on the command line,
expect the private key to be in a file with the correct
permissions.
* [utils] Fixes undeclared `activeChroniclesStream` on Windows
* [build] update nim-ethers to include PR #52
Co-authored-by: Eric Mastro <eric.mastro@gmail.com>
* [cli] Better error messages when reading eth private key
Co-authored-by: Eric Mastro <eric.mastro@gmail.com>
* [integration] simplify reading of cmd line arguments
Co-authored-by: Eric Mastro <eric.mastro@gmail.com>
* [build] update to latest version of nim-ethers
* [contracts] updated contract address for Taiko L2
* [build] update codex contracts to latest version
---------
Co-authored-by: Eric Mastro <eric.mastro@gmail.com>
* [sales] remove availability check before adding to slot queue
* [sales] add missing return statement
* [tests] remove 'eventuallyCheck' helper
* [sales] remove reservations from slot queue
* [tests] rename module `eventually` -> `always`
* [sales] increase slot queue size
Because it will now also hold items for which we haven't
checked availability yet.
* Improve integration testing client (CodexClient) and json serialization
The current client used for integration testing against the REST endpoints for Codex accepts and passes primitive types. This caused a hard to diagnose bug where a `uint` was not being deserialized correctly.
In addition, the json de/serializing done between the CodexClient and REST client was not easy to read and was not tested.
These changes bring non-primitive types to most of the CodexClient functions, allowing us to lean on the compiler to ensure we're providing correct typings. More importantly, a json de/serialization util was created as a drop-in replacement for the std/json lib, with the main two differences being that field serialization is opt-in (instead of opt-out as in the case of json_serialization) and serialization errors are captured and logged, making debugging serialization issues much easier.
* Update integration test to use nodes=2 and tolerance=1
* clean up
* logs
* poll log
* more logs
* time log for upload steps
* Adds metric and log for block retrieval time
* adds some logging
* move logging for storestream block indices
* Log at start and end of block iteration
* applies branch blockstore-bugfix
* Cleanup
* Cleanup
Add handling of empty blocks in the RepoStore.
* Add empty block handling to repostore for put, del, has
Also added tests for all empty block handling blockstore operations. This showed there was an ambiguous identifier present for `hasBlock`, so one of the two `hasBlock` definitions was removed in `repostore`.
* Change CacheStore to RepoStore in testerasure
As CacheStore is not used in the node, update the Datastore used in the erasure coding tests to be a RepoStore. This ensures that the K > 1 cases are being tested, where they will produce empty padding blocks in the erasure-coded manifests.
* extra utilities and tweaks
* add atlas lock
* update ignores
* break build into it's own script
* update url rules
* base off codexdht's
* compile fixes for Nim 1.6.14
* update submodules
* convert mapFailure to procs to work around type resolution issues
* add toml parser for multiaddress
* change error type on keyutils
* bump nimbus build to use 1.6.14
* update gitignore
* adding new deps submodules
* bump nim ci version
* even more fixes
* more libp2p changes
* update keys
* fix eventually function
* adding coverage test file
* move coverage to build.nims
* use nimcache/coverage
* move libp2p import for tests into helper.nim
* remove named bin
* bug fixes for networkpeers (from Dmitriy)
---------
Co-authored-by: Dmitriy Ryajov <dryajov@gmail.com>
* Simplify `.then` (promise api) and tests
* Remove tracked future when cancelled. Add tracked future tests
* Track and cancel statemachine futures
The futures created in each asyncstatemachine instance are tracked, and each future is cancelled and waited in `stop`.
Change `asyncstatemachine.stop` to be async so `machine.trackedFutures.cancelAndWait` could be called.
Add a constructor for `asyncstatemachine` that initialises the `trackedFutures` instance, and call the constructor from derived class constructors.
## Slot queue
Adds a slot queue, as per the [slot queue design](https://github.com/codex-storage/codex-research/blob/master/design/sales.md#slot-queue).
Any time storage is requested, all slots from that request are immediately added to the queue. Finished, Canclled, Failed requests remove all slots with that request id from the queue. SlotFreed events add a new slot to the queue and SlotFilled events remove the slot from the queue. This allows popping of a slot each time one is processed, making things much simpler.
When an entire request of slots is added to the queue, the slot indices are shuffled randomly to hopefully prevent nodes that pick up the same storage requested event from clashing on the first processed slot index. This allowed removal of assigning a random slot index in the SalePreparing state and it also ensured that all SalesAgents will have a slot index assigned to them at the start thus the removal of the optional slotIndex.
Remove slotId from SlotFreed event as it was not being used. RequestId and slotIndex were added to the SlotFreed event earlier and those are now being used
The slot queue invariant that prioritises queue items added to the queue relies on a scoring mechanism to sort them based on the [sort order in the design document](https://github.com/codex-storage/codex-research/blob/master/design/sales.md#sort-order).
When a storage request is handled by the sales module, a slot index was randomly assigned and then the slot was filled. Now, a random slot index is only assigned when adding an entire request to the slot queue. Additionally, the slot is checked that its state is `SlotState.Free` before continuing with the download process.
SlotQueue should always ensure the underlying AsyncHeapQueue has one less than the maximum items, ensuring the SlotQueue can always have space to add an additional item regardless if it’s full or not.
Constructing `SlotQueue.workers` in `SlotQueue.new` calls `newAsyncQueue` which causes side effects, so the construction call had to be moved to `SlotQueue.start`.
Prevent loading request from contract (network request) if there is an existing item in queue for that request.
Check availability before adding request to queue.
Add ability to query market contract for past events. When new availabilities are added, the `onReservationAdded` callback is triggered in which past `StorageRequested` events are queried, and those slots are added to the queue (filtered by availability on `push` and filtered by state in `SalePreparing`).
#### Request Workers
Limit the concurrent requests being processed in the queue by using a limited pool of workers (default = 3). Workers are in a data structure of type `AsyncQueue[SlotQueueWorker]`. This allows us to await a `popFirst` for available workers inside of the main SlotQueue event loop
Add an `onCleanUp` that stops the agents and removes them from the sales module agent list. `onCleanUp` is called from sales end states (eg ignored, cancelled, finished, failed, errored).
Add a `doneProcessing` future to `SlotQueueWorker` to be completed in the `OnProcessSlot` callback. Each `doneProcessing` future created is cancelled and awaited in `SlotQueue.stop` (thanks to `TrackableFuturees`), which forced `stop` to become async.
- Cancel dispatched workers and the `onProcessSlot` callbacks, prevents zombie callbacks
#### Add TrackableFutures
Allow tracking of futures in a module so they can be cancelled at a later time. Useful for asyncSpawned futures, but works for any future.
### Sales module
The sales module needed to subscribe to request events to ensure that the request queue was managed correctly on each event. In the process of doing this, the sales agents were updated to avoid subscribing to events in each agent, and instead dispatch received events from the sales module to all created sales agents. This would prevent memory leaks on having too many eventemitters subscribed to.
- prevent removal of agents from sales module while stopping, otherwise the agents seq len is modified while iterating
An additional sales agent state was added, `SalePreparing`, that handles all state machine setup, such as retrieving the request and subscribing to events that were previously in the `SaleDownloading` state.
Once agents have parked in an end state (eg ignored, cancelled, finished, failed, errored), they were not getting cleaned up and the sales module was keeping a handle on their reference. An `onCleanUp` callback was created to be called after the state machine enters an end state, which could prevent a memory leak if the number of requests coming in is high.
Move the SalesAgent callback raises pragmas from the Sales module to the proc definition in SalesAgent. This avoids having to catch `Exception`.
- remove unneeded error handling as pragmas were moved
Move sales.subscriptions from an object containing named subscriptions to a `seq[Subscription]` directly on the sales object.
Sales tests: shut down repo after sales stop, to fix SIGABRT in CI
### Add async Promise API
- modelled after JavaScript Promise API
- alternative to `asyncSpawn` that allows handling of async calls in a synchronous context (including access to the synchronous closure) with less additional procs to be declared
- Write less code, catch errors that would otherwise defect in asyncspawn, and execute a callback after completion
- Add cancellation callbacks to utils/then, ensuring cancellations are handled properly
## Dependencies
- bump codex-contracts-eth to support slot queue (https://github.com/codex-storage/codex-contracts-eth/pull/61)
- bump nim-ethers to 0.5.0
- Bump nim-json-rpc submodule to 0bf2bcb
---------
Co-authored-by: Jaremy Creechley <creechley@gmail.com>
* Adds metrics to block exchange.
* Adds metrics to purchasing
* Adds metrics to upload and download API
* Adds metrics to the repo store
* Fixes exception in repostore start.
* Merge managed to mess up indentation.
* setup to use env variable for parallel tests
* use explicit targets
* use target in includes
* test windows split
* try simpler logic
* only use include in ci.yml
* add cpu
* fix name
* re-add unit tests!
* restore coverage
* not sure why env broke there
* startup node for part 1 & 2 tests
* fixup part 1 & 2 tests
* split windows into 3!
* Adds sequence diagram for local download
* Adds network download flow
* makes node properly request block when presence-list is received
* starting to work :O
* Fixes fully connected download test up to 20 nodes.
* Better sequence diagram of network block resolution
* Cleans up comments and traces.
* Accidentally deleted important else
* Review comments by Dmitriy
---------
Co-authored-by: benbierens <thatbenbierens@gmail.com>
Previously it could take up to one second to complete
the future. This messed with the timings in the
integration tests and made them less predictable.
Goal is to provide documentation and to enable conf utils byte params.
* Create byte units NByte and plumb through in size locations.
* add json serde
* plumb parseDuration to conf
Eric
Adam Uhlíř
Slava
Dmitriy Ryajov
markspanbroek
Ben Bierens
Vaclav Pavlin
Tomasz Bekas
Jaremy Creechley
jessiebroke