Commit Graph

10 Commits

Author SHA1 Message Date
Jacek Sieka 05ffe7b2bf
Prune `BlockRef` on finalization (#3513)
Up til now, the block dag has been using `BlockRef`, a structure adapted
for a full DAG, to represent all of chain history. This is a correct and
simple design, but does not exploit the linearity of the chain once
parts of it finalize.

By pruning the in-memory `BlockRef` structure at finalization, we save,
at the time of writing, a cool ~250mb (or 25%:ish) chunk of memory
landing us at a steady state of ~750mb normal memory usage for a
validating node.

Above all though, we prevent memory usage from growing proportionally
with the length of the chain, something that would not be sustainable
over time -  instead, the steady state memory usage is roughly
determined by the validator set size which grows much more slowly. With
these changes, the core should remain sustainable memory-wise post-merge
all the way to withdrawals (when the validator set is expected to grow).

In-memory indices are still used for the "hot" unfinalized portion of
the chain - this ensure that consensus performance remains unchanged.

What changes is that for historical access, we use a db-based linear
slot index which is cache-and-disk-friendly, keeping the cost for
accessing historical data at a similar level as before, achieving the
savings at no percievable cost to functionality or performance.

A nice collateral benefit is the almost-instant startup since we no
longer load any large indicies at dag init.

The cost of this functionality instead can be found in the complexity of
having to deal with two ways of traversing the chain - by `BlockRef` and
by slot.

* use `BlockId` instead of `BlockRef` where finalized / historical data
may be required
* simplify clearance pre-advancement
* remove dag.finalizedBlocks (~50:ish mb)
* remove `getBlockAtSlot` - use `getBlockIdAtSlot` instead
* `parent` and `atSlot` for `BlockId` now require a `ChainDAGRef`
instance, unlike `BlockRef` traversal
* prune `BlockRef` parents on finality (~200:ish mb)
* speed up ChainDAG init by not loading finalized history index
* mess up light client server error handling - this need revisiting :)
2022-03-17 17:42:56 +00:00
zah 9c1ff78f84
Fix a reward calculation bug affecting Prater epoch 64781 (#3428)
To calculate the deltas correctly, the `process_inactivity_updates` function
must be called before the rewards and penalties processing code in order to
update the `inactivity_scores` field in the state. This would have required
duplicating more logic from the spec in the ncli modules, so I've decided to
pay the price of introducing a run-time copy of the state at each epoch which
eliminates the need to duplicate logic (both for this fix and the previous one).

Other changes:

* Fixes for the read-only mode of the `BeaconChainDb`
* Fix an uint64 underflow in the debug output procedure for printing
  balance deltas
* Allow Bellatrix states in the reward computation helpers
2022-02-22 14:14:17 +02:00
tersec 7de3f00f35
generic putCorruptState; {Merge=>Bellatrix}BeaconStateNoImmutableValidators (#3427) 2022-02-21 12:55:56 +01:00
tersec 79761c78a4
proc -> func, mainly in spec/state transition and adjecent modules (#3405) 2022-02-17 11:53:55 +00:00
Zahary Karadjov ac16eb4691 Streamline the validator reward analysis
Notable improvements:

* A separate aggregation pass is no longer required.

* The user can opt to produce only aggregated data
  (resuing in a much smaller data set).

* Large portion of the number cruching in Jupyter is now done in C
  through the rich DataFrames API.

* Added support for comparisons against the "median" validator
  performance in the network.
2022-02-01 11:30:14 +02:00
tersec 29e2169585
phase 0 & altair beacon chain and altair validator spec URL updates (#3339) 2022-01-29 13:53:31 +00:00
Zahary Karadjov 49b7daa39d [ncli_db] bugfix: take into account finalization delay in reward calc post Altair
This fixes a problem affecting Prater's epoch 64444.
2022-01-28 12:03:23 +02:00
Zahary Karadjov 54a745cb0e Bugfix: Take into account the finalization delay in the ncli_db rewards calculation
This fixes a reward calculation error affecting Prater's epoch 31256
2022-01-23 23:10:56 +02:00
tersec 9c0c9c98ce
complete switch to beacon_chain/specs/datatypes/bellatrix (#3295) 2022-01-18 13:36:52 +00:00
Zahary Karadjov 47f1f7ff1a More efficient reward data persistance; Address review comments
The new format is based on compressed CSV files in two channels:

* Detailed per-epoch data
* Aggregated "daily" summaries

The use of append-only CSV file speeds up significantly the epoch
processing speed during data generation. The use of compression
results in smaller storage requirements overall. The use of the
aggregated files has a very minor cost in both CPU and storage,
but leads to near interactive speed for report generation.

Other changes:

- Implemented support for graceful shut downs to avoid corrupting
  the saved files.

- Fixed a memory leak caused by lacking `StateCache` clean up on each
  iteration.

- Addressed review comments

- Moved the rewards and penalties calculation code in a separate module

Required invasive changes to existing modules:

- The `data` field of the `KeyedBlockRef` type is made public to be used
  by the validator rewards monitor's Chain DAG update procedure.

- The `getForkedBlock` procedure from the `blockchain_dag.nim` module
  is made public to be used by the validator rewards monitor's Chain DAG
  update procedure.
2022-01-18 01:56:56 +02:00