Commit Graph

91 Commits

Author SHA1 Message Date
Jacek Sieka c4ce59e55b
Assorted logging improvements (#3237)
* log doppelganger detection when it activates and when it causes missed
duties
* less prominent eth1 sync progress
* log in-progress sync at notice only when actually missing duties
* better detail in replay log
* don't log finalization checkpoints - this is quite verbose when
syncing and already included in "Slot start"
2022-01-03 22:18:49 +01:00
Jacek Sieka 7ec97a6b35
Fix missing checkpoint states` (#3225)
With the right sequence of events (for example a REST request or a
validation), it can happen that the first traversal across a state
checkpoint boundary is done without storing that state on disk - this
causes problens when replaying states, because now states may be missing
from the database.

Here, we simply avoid using the caches when advancing a state that will
go into the database, ensuring that the information lost during caching
always is permanently stored.

* fix recursion bug in `isProposed`
2021-12-30 12:33:03 +01:00
tersec 0d4e49f946
Merge fork gossip support (#3213)
* Merge fork gossip support

* index directly by BeaconStateFork and remove debugging log statement
2021-12-21 15:24:23 +01:00
Jacek Sieka 1021e3324e
Revert writing backfill root to database (#3215)
Introduced in #3171, it turns out we can just follow the block headers
to achieve the same effect

* leaves the constant in the code so as to avoid confusion when reading
database that had the constant written (such as the fleet nodes and
other unstable users)
2021-12-21 11:40:14 +01:00
Jacek Sieka c270ec21e4
Validator monitoring (#2925)
Validator monitoring based on and mostly compatible with the
implementation in Lighthouse - tracks additional logs and metrics for
specified validators so as to stay on top on performance.

The implementation works more or less the following way:
* Validator pubkeys are singled out for monitoring - these can be
running on the node or not
* For every action that the validator takes, we record steps in the
process such as messages being seen on the network or published in the
API
* When the dust settles at the end of an epoch, we report the
information from one epoch before that, which coincides with the
balances being updated - this is a tradeoff between being correct
(waiting for finalization) and providing relevant information in a
timely manner)
2021-12-20 20:20:31 +01:00
Jacek Sieka 03005f48e1
Backfill support for ChainDAG (#3171)
In the ChainDAG, 3 block pointers are kept: genesis, tail and head. This
PR adds one more block pointer: the backfill block which represents the
block that has been backfilled so far.

When doing a checkpoint sync, a random block is given as starting point
- this is the tail block, and we require that the tail block has a
corresponding state.

When backfilling, we end up with blocks without corresponding states,
hence we cannot use `tail` as a backfill pointer - there is no state.

Nonetheless, we need to keep track of where we are in the backfill
process between restarts, such that we can answer GetBeaconBlocksByRange
requests.

This PR adds the basic support for backfill handling - it needs to be
integrated with backfill sync, and the REST API needs to be adjusted to
take advantage of the new backfilled blocks when responding to certain
requests.

Future work will also enable moving the tail in either direction:
* pruning means moving the tail forward in time and removing states
* backwards means recreating past states from genesis, such that
intermediate states are recreated step by step all the way to the tail -
at that point, tail, genesis and backfill will match up.
* backfilling is done when backfill != genesis - later, this will be the
WSS checkpoint instead
2021-12-13 14:36:06 +01:00
Jacek Sieka 9f27f0d97c
BlockId reform (#3176)
* BlockId reform

Introduce `BlockId` that helps track a root/slot pair - this prepares
the codebase for backfilling and handling out-of-dag blocks

* move block dag code to separate module
* fix finalised state root in REST event stream
* fix finalised head computation on head update, when starting from
checkpoint
* clean up chaindag init
* revert `epochAncestor` change in introduced in #3144 that would return
an epoch ancestor from the canoncial history instead of the given
history, causing `EpochRef` keys to point to the wrong block
2021-12-09 19:06:21 +02:00
Jacek Sieka 069bccd51b
batch-verify sync messages for a small perf boost (#3151)
* batch-verify sync messages for a small perf boost

Generally reuses the same structure as attestation and aggregate
verification

* normalize `signatures` and `signature_batch` to use the same pattern
of verification
* normalize parameter names, order etc for signature stuff in general
* avoid calling `blsSign` directly - instead, go through `signatures`
consistently
2021-12-09 14:56:54 +02:00
tersec 2ca28fb861
Merge BeaconBlock gossip validation (#3165)
* Merge BeaconBlock gossip validation

* figure/ground inversion

* revert cosmetic cleanups to reduce merge conflicts
2021-12-08 17:29:22 +00:00
Etan Kissling 38e64b3441 cleanup sync subcommittee accessors
This removes some dead code from `getSubcommitteePositionsAux` which is
no longer needed since the introduction of `SyncCommitteeCache`.
This also cleans up some formatting, uses `let` instead of `var` where
possible, and uses implicit `pairs` in one case for consistency.
2021-12-07 18:17:03 +02:00
Jacek Sieka 89d6a1b403
Introduce slot->BlockRef mapping for finalized chain (#3144)
* Introduce slot->BlockRef mapping for finalized chain

The finalized chain is linear, thus we can use a seq to lookup blocks by
slot number.

Here, we introduce such a seq, even though in the future, it should
likely be backed by a database structure instead, or, more likely, a
flat era file with a flat lookup index.

This dramatically speeds up requests by slot, such as those coming from
the REST interface or GetBlocksByRange, as these are currently served by
a linear iteration from head.

* fix REST block requests to not return blocks from an earlier slot when
the given slot is empty
* fix StateId interpretation such that it doesn't treat state roots as
block roots
* don't load full block from database just to return its root
2021-12-06 20:52:35 +02:00
Jacek Sieka 1a8b7469e3
move quarantine outside of chaindag (#3124)
* move quarantine outside of chaindag

The quarantine has been part of the ChainDAG for the longest time, but
this design has a few issues:

* the function in which blocks are verified and added to the dag becomes
reentrant and therefore difficult to reason about - we're currently
using a stateful flag to work around it
* quarantined blocks bypass the processing queue leading to a processing
stampede
* the quarantine flow is unsuitable for orphaned attestations - these
should also should be quarantined eventually

Instead of processing the quarantine inside ChainDAG, this PR moves
re-queueing to `block_processor` which already is responsible for
dealing with follow-up work when a block is added to the dag

This sets the stage for keeping attestations in the quarantine as well.

Also:

* make `BlockError` `{.pure.}`
* avoid use of `ValidationResult` in block clearance (that's for gossip)
2021-12-06 10:49:01 +01:00
tersec 4378f3f096
almost all remaining ethereum/{eth2.0-specs -> consensus-specs} (#3158) 2021-12-03 20:01:13 +00:00
Jacek Sieka aa1dea03cd
speed up gossip and sync block validation (#3143)
* avoid recomputing hash for block signature check
* check block slot match before hitting the database
2021-12-01 10:52:40 +01:00
Etan Kissling eb777a6c8b allow `withState` to be called multiple times
This allows `blockchain_dag`'s `withState` template to be called more
than once in a single function. This led to a compilation error before
because the injected variables and functions shared the same scope.
2021-11-29 15:24:12 +02:00
Jacek Sieka 9c2f43ed0e
Speed up altair block processing 2x (#3115)
* Speed up altair block processing >2x

Like #3089, this PR drastially speeds up historical REST queries and
other long state replays.

* cache sync committee validator indices
* use ~80mb less memory for validator pubkey mappings
* batch-verify sync aggregate signature (fixes #2985)
* document sync committee hack with head block vs sync message block
* add batch signature verification failure tests

Before:

```
../env.sh nim c -d:release -r ncli_db --db:mainnet_0/db bench --start-slot:-1000
All time are ms
     Average,       StdDev,          Min,          Max,      Samples,         Test
Validation is turned off meaning that no BLS operations are performed
    5830.675,        0.000,     5830.675,     5830.675,            1, Initialize DB
       0.481,        1.878,        0.215,       59.167,          981, Load block from database
    8422.566,        0.000,     8422.566,     8422.566,            1, Load state from database
       6.996,        1.678,        0.042,       14.385,          969, Advance slot, non-epoch
      93.217,        8.318,       84.192,      122.209,           32, Advance slot, epoch
      20.513,       23.665,       11.510,      201.561,          981, Apply block, no slot processing
       0.000,        0.000,        0.000,        0.000,            0, Database load
       0.000,        0.000,        0.000,        0.000,            0, Database store
```

After:

```
    7081.422,        0.000,     7081.422,     7081.422,            1, Initialize DB
       0.553,        2.122,        0.175,       66.692,          981, Load block from database
    5439.446,        0.000,     5439.446,     5439.446,            1, Load state from database
       6.829,        1.575,        0.043,       12.156,          969, Advance slot, non-epoch
      94.716,        2.749,       88.395,      100.026,           32, Advance slot, epoch
      11.636,       23.766,        4.889,      205.250,          981, Apply block, no slot processing
       0.000,        0.000,        0.000,        0.000,            0, Database load
       0.000,        0.000,        0.000,        0.000,            0, Database store
```

* add comment
2021-11-24 13:43:50 +01:00
Jacek Sieka f19a497eec
ncli_db: add putState, putBlock (#3096)
* ncli_db: add putState, putBlock

These tools allow modifying an existing nimbus database for the purpose
of recovery or reorg, moving the head, tail and genesis to arbitrary
points.

* remove potentially expensive `putState` in `BeaconStateDB`
* introduce `latest_block_root` which computes the root of the latest
applied block from the `latest_block_header` field (instead of passing
it in separately)
* avoid some unnecessary BeaconState copies during init
* discover https://github.com/nim-lang/Nim/issues/19094
* prefer `HashedBeaconState` in a few places to avoid recomputing state
root
* fetch latest block root from state when creating blocks
* harden `get_beacon_proposer_index` against invalid slots and document
* move random spec function tests to `test_spec.nim`
* avoid unnecessary state root computation before block proposal
2021-11-18 13:02:43 +01:00
Jacek Sieka 222674b203
better logging on invalid database (#3097)
* remove redundant test report
2021-11-13 17:27:28 +01:00
Jacek Sieka ec650c7fd7
Support starting from altair (#3054)
* Support starting from altair

* hide `finalized-checkpoint-` - they are incomplete and usage may cause
crashes
* remove genesis detection code (broken, obsolete)
* enable starting ChainDAG from altair checkpoints - this is a
prerequisite for checkpoint sync (TODO: backfill)
* tighten checkpoint state conditions
* show error when starting from checkpoint with existing database (not
supported)
* print rest-compatible JSON in ncli/state_sim
* altair/merge support in ncli
* more altair/merge support in ncli_db
* pre-load header to speed up loading
* fix forked block decoding
2021-11-10 13:39:08 +02:00
Jacek Sieka ea0a191723
Better REST/RPC error messages (#3046)
* Better REST/RPC error messages
* homogenise block logging (root first)
* homegenise message verification pipeline (verify in
`gossip_verification`, act in `eth2_processor`)
* use `subcommitteeIdx` consistently
* log each sent contribution
* fix block_sim
* fix block topic
* don't recalc root on gossip block validation
* move position loop into sync pool
2021-11-05 17:39:47 +02:00
Jacek Sieka a086cf01ac
altair fork handling cleanups (#3050)
* fix stack overflow crash in REST/debug/getStateV2
* introduce `ForkyXxx` for generic type matching of `Xxx` across
branches (SomeHashedBeaconState -> ForkyHashedBeaconState et al) -
`Some` is already used for other types of type classes
* consolidate function naming in BeaconChainDB, use some generics
* import `forks.nim` from other spec modules and move `Forked*` helpers
around to resolve circular imports
* remove `ForkedBeaconState`, use `ForkedHashedBeaconState` throughout
(less data shuffling between the types)
* fix several cases of states being stored on stack in tests, causing
random failures on some platforms
* remove reading json support from ncli - this should be ported to the
rest json reading instead (doesn't currently work because stack sizes)
2021-11-05 08:34:34 +01:00
Jacek Sieka 233d756518
Logging and startup improvements (#3038)
* Logging and startup improvements

Color support for released binaries!

* startup scripts no longer log to file by default - this only affects
source builds - released binaries don't support file logging
* add --log-stdout option to control logging to stdout (colors, json)
* detect tty:s vs redirected logs and log accordingly
* add option to disable log colors at runtime
* simplify several "common" logs, showing the most important information
earlier and more clearly
* remove line numbers / file information / tid - these take up space and
are of little use to end users
  * still enabled in debug builds and tools
* remove `testnet_servers_image` compile-time option
* server images, released binaries and compile-from-source now offer
the same behaviour and features
* fixes https://github.com/status-im/nimbus-eth2/issues/2326
* fixes https://github.com/status-im/nimbus-eth2/issues/1794
* remove instanteneous block speed from sync message, keeping only
average

before:

```
INF 2021-10-28 16:45:59.000+02:00 Slot start                                 topics="beacnde" tid=386429 file=nimbus_beacon_node.nim:884 lastSlot=2384027 wallSlot=2384028 delay=461us84ns peers=0 head=75a10ee5:3348 headEpoch=104 finalized=cd6804ba:3264 finalizedEpoch=102 sync="wwwwwwwwww:0:0.0000:0.0000:00h00m (3348)"
INF 2021-10-28 16:45:59.046+02:00 Slot end                                   topics="beacnde" tid=386429 file=nimbus_beacon_node.nim:821 slot=2384028 nextSlot=2384029 head=75a10ee5:3348 headEpoch=104 finalizedHead=cd6804ba:3264 finalizedEpoch=102 nextAttestationSlot=-1 nextProposalSlot=-1 nextActionWait=n/a
```

after:

```
INF 2021-10-28 22:43:23.033+02:00 Slot start                                 topics="beacnde" slot=2385815 epoch=74556 sync="DDPDDPUDDD:10:5.2258:01h19m (2361088)" peers=37 head=eacd2dae:2361096 finalized=73782:a4751487 delay=33ms687us715ns
INF 2021-10-28 22:43:23.291+02:00 Slot end                                   topics="beacnde" slot=2385815 nextActionWait=n/a nextAttestationSlot=-1 nextProposalSlot=-1 head=eacd2dae:2361096
```

* fix comment

* documentation updates

* mention `--log-file` may be deprecated in the future
* update various docs
2021-11-02 18:06:36 +01:00
Jacek Sieka 9cf32c3748 clean up sync subcommittee handling
* `SyncCommitteeIndex` -> `SyncSubcommitteeIndex`
* `syncCommitteePeriod` -> `sync_committee_period` (spec spelling)
* tighten period comparisons
* fix assert when validating committee message with non-altair state in
REST api
2021-10-20 22:59:13 +03:00
Jacek Sieka c40cc6cec1 clean up fork enum and field names
* single naming strategy
* simplify some fork code
* simplify forked block production
2021-10-19 11:06:38 +03:00
Jacek Sieka 5b33783898
load altair state from database on startup (#2994)
* fixes replay from last phase0 block on startup
* better forked block loading
2021-10-18 14:32:54 +02:00
Eugene Kabanov 7319f150e8
Number of REST fixes. (#2987)
* Initial commit.

* Fix path.

* Add validator keys to indices cache mechanism.
Move syncComitteeParticipants to common place.

* Fix sync participants order issue.

* Fix error code when state could not be found.
Refactor `state/validators` to use keysToIndices mechanism.

* Fix RestValidatorIndex to ValidatorIndex conversion TODOs.

* Address review comments.

* Fix REST test rules.
2021-10-14 12:38:38 +02:00
Jacek Sieka f90b2b8b1f
reward accounting for altair+ (#2981)
Similar to the existing `RewardInfo`, this PR adds the infrastructure
needed to export epoch processing information from altair+. Because
accounting is done somewhat differently, the PR uses a fork-specific
object to extrct the information in order to make the cost on the spec
side low.

* RewardInfo -> EpochInfo, ForkedEpochInfo
* use array for computing new sync committee
* avoid repeated total active balance computations in block processing
* simplify proposer index check
* simplify epoch transition tests
* pre-compute base increment and reuse in epoch processing, and a few
other small optimizations

This PR introduces the type and does the heavy lifting in terms of
refactoring - the tools that use the accounting will need separate PR:s
(as well as refinements to the exportred information)
2021-10-13 16:24:36 +02:00
tersec 2eb9a608a4
add payloadId; add merge vector test script; remove consensusValidated (#2982) 2021-10-13 16:08:50 +02:00
Jacek Sieka fabec894dd
harden sync sub committee selection (#2965)
* harden sync sub committee selection

also turn it into an iterator

* fix test and warning
2021-10-07 13:19:47 +00:00
Ștefan Talpalaru 359937fa70
interop metrics (#2964)
https://github.com/ethereum/beacon-metrics/blob/master/metrics.md#interop-metrics
2021-10-07 06:19:07 +00:00
Etan Kissling 9ee134324b
allow `withXxx` to access fork-specific fields (#2943)
So far, `withState` and `withBlck` templates could only be used to have
convenience access to fork-agnostic BeaconState and BeaconBlock fields.
This patch:
- injects an additional `stateFork` constant that allows to use
  `when` expressions to also access Altair and Merge-specific fields.
- introduces a `withStateAndBlck` template to support operating on both
  a `BeaconState` and `BeaconBlock` at a time.
- makes sync committee related functions Merge aware.
- changes a couple if-else trees for forks into case statements so that
  forgotten future forks are promoted to compile-time errors.
2021-10-06 20:05:06 +03:00
Etan Kissling 2bbffbde10
abort compile when fork epoch is forgotten (#2939)
There are a few locations in the code that compare the current epoch to
the various FORK_EPOCH constants and branch off into fork-specific code.
When a new fork is introduced, it is sometimes forgotten to update all
of those branch locations. This patch introduces a compile-time check
that ensures that all branches need to be covered exhaustively. This is
done by replacing if-elif structures with case expressions.
2021-10-04 08:31:21 +00:00
tersec 6b3bf7eb7b
merge hardfork database support (#2911)
* merge hardfork database support

* working block_sim

* recreate state transition changes
2021-09-30 01:07:24 +00:00
Etan Kissling 01a9b275ec
handle duplicate pubkeys in sync committee (#2902)
When sync committee message handling was introduced in #2830, the edge
case of the same validator being selected multiple times as part of a
sync subcommittee was not covered. Not handling that edge case makes
sync contributions have a lower-than-expected participation rate as each
sync validator is only counted up through once per subcommittee.
This patch ensures that this edge case is properly covered.
2021-09-28 07:44:20 +00:00
tersec 2b2846b468
implement forked merge state/block support (#2890)
* implement forked state/block support

* merge support for containsOrphan; import cleanup; 80-column lines

* add merge block header operations and slot sanity fixture

* add epoch state transition tests; implement is_valid_gas_limit(), is_merge_block(), is_execution_enabled(), and compute_timestamp_at_slot()

* implement process_execution_payload() and add merge deposit operations tests

* add merge block sanity tests

* add merge case to syncCommitteeParticipants

* v1.1.0-beta.5 updates

* reduce getTestStates-based memory usage; don't try to REST-serialize ExecutionPayload transactions without underlying support

* add execution payload tests; switch var to let in tests/official/
2021-09-27 14:22:58 +00:00
Eugene Kabanov 0c635334a2
Sync committee related REST API implementation. (#2856) 2021-09-24 01:13:25 +03:00
Eugene Kabanov b566d4657f
REST /eth/v1/events API call implementation. (#2878)
* Placing callbacks into strategic places.

* Initial events call implementation.

* Post rebase fixes.

* Change addSyncContribution() implementation.

* Add `attestation-sent` event.
Remove gcsafe, raises from callbacks implementations.
Move `attestation-received` fire at the end of attestation processing.

* Address review comments.
2021-09-22 14:17:15 +02:00
Dustin Brody 6638476b5f discard putative blocks from invalid hardforks 2021-09-16 16:18:40 +03:00
tersec 166e22a43b
sync committee message pool and gossip validation (#2830) 2021-08-28 10:40:01 +00:00
Jacek Sieka ba06f13942
cleanups (#2809)
* cleanups

* use ForkedTrustedSignedBeaconBlock.ionit where appropriate
* move `is_aggregator` to `spec/`
* use `errReject` in a few more places
* update enr fork id when time is auspicious
* use network broadcast functions

* Return Ignore for aggregate signature validation timeouts

...consistently between aggregates and attestations.

* clean up some more reject/ignore rules
* shorten texts a bit

* errReject->checkedReject, use err helpers throughout

* get rid of quarantine in exitpool as well
2021-08-24 21:49:51 +02:00
tersec 4678a2bee7
move BeaconClock from ChainDAG to BeaconNode (#2796) 2021-08-20 08:58:15 +00:00
Jacek Sieka a7a65bce42
disentangle eth2 types from the ssz library (#2785)
* reorganize ssz dependencies

This PR continues the work in
https://github.com/status-im/nimbus-eth2/pull/2646,
https://github.com/status-im/nimbus-eth2/pull/2779 as well as past
issues with serialization and type, to disentangle SSZ from eth2 and at
the same time simplify imports and exports with a structured approach.

The principal idea here is that when a library wants to introduce SSZ
support, they do so via 3 files:

* `ssz_codecs` which imports and reexports `codecs` - this covers the
basic byte conversions and ensures no overloads get lost
* `xxx_merkleization` imports and exports `merkleization` to specialize
and get access to `hash_tree_root` and friends
* `xxx_ssz_serialization` imports and exports `ssz_serialization` to
specialize ssz for a specific library

Those that need to interact with SSZ always import the `xxx_` versions
of the modules and never `ssz` itself so as to keep imports simple and
safe.

This is similar to how the REST / JSON-RPC serializers are structured in
that someone wanting to serialize spec types to REST-JSON will import
`eth2_rest_serialization` and nothing else.

* split up ssz into a core library that is independendent of eth2 types
* rename `bytes_reader` to `codec` to highlight that it contains coding
and decoding of bytes and native ssz types
* remove tricky List init overload that causes compile issues
* get rid of top-level ssz import
* reenable merkleization tests
* move some "standard" json serializers to spec
* remove `ValidatorIndex` serialization for now
* remove test_ssz_merkleization
* add tests for over/underlong byte sequences
* fix broken seq[byte] test - seq[byte] is not an SSZ type

There are a few things this PR doesn't solve:

* like #2646 this PR is weak on how to handle root and other
dontSerialize fields that "sometimes" should be computed - the same
problem appears in REST / JSON-RPC etc

* Fix a build problem on macOS

* Another way to fix the macOS builds

Co-authored-by: Zahary Karadjov <zahary@gmail.com>
2021-08-18 20:57:58 +02:00
Jacek Sieka 7a622e8505
rework spec imports (#2779)
The spec imports are a mess to work with, so this branch cleans them up
a bit to ensure that we avoid generic sandwitches and that importing
stuff generally becomes easier.

* reexport crypto/digest/presets because these are part of the public
symbol set of the rest of the spec types
* don't export `merge` types from `base` - this causes circular deps
* fix circular deps in `ssz/spec_types` - this is the first step in
disentangling ssz from spec
* be explicit about phase0 vs altair - longer term, `altair` will become
the "natural" type set, then merge and so on, so no point in giving
`phase0` special preferential treatment
2021-08-12 13:08:20 +00:00
Jacek Sieka 9697b73e71
forkedbeaconstate_helpers -> forks (#2772)
Simpler module name for stuff that covers forks

* check that runtime config matches database state
* also include some assorted altair cleanups
* use "standard" genesis fork in local testnet to work around missing
runtime config support
2021-08-10 22:46:35 +02:00
Jacek Sieka a663ed65f4
Merge branch 'merge-stable' into unstable 2021-08-09 15:00:58 +02:00
tersec 2afe2802b6
altair topic switching (#2767)
* altair topic switching

* remove validate{Committee,Validator}IndexOr unused within branch
2021-08-09 12:54:45 +00:00
Jacek Sieka 7bb76a6cd1
Merge remote-tracking branch 'origin/stable' into merge-stable 2021-08-09 13:14:28 +02:00
Jacek Sieka ee79c10a7d
update validator key cache on startup (#2760)
* update validator key cache on startup

Versions prior to 1.1.0 do not write a validator key cache at all.

Versions from 1.4.0 and upwards require an immutable validator key cache
to verify blocks - normally, block verification fills the cache but that
assumes that at least one block was verified by a version that has the
key cache.

Taken together, this breaks direct upgrades from anything <1.1.0 to
1.4.0.

The fix is simply to refresh fill the cache from an existing state on
startup.

* also log serious block validation failures at info level
2021-08-05 11:26:10 +03:00
tersec a2c1b96ac9
prevent resyncing from genesis with altair head block (#2750) 2021-08-01 10:20:43 +02:00
tersec e4afc36d71
use ForkedTrustedSignedBeaconBlock (#2720)
* use ForkedTrustedSignedBeaconBlock

* remove --subscribe-all-subnets

* https://ethereum.github.io/eth2.0-APIs/#/Beacon/getBlock implementation was passing through forked beaconblocks
2021-07-14 12:18:52 +00:00