- Detects if the consensus process is "stalled". If it is, then we can declare a
consensus and end successfully even if we do not have 80% agreement on
our proposal.
- "Stalled" is defined as:
- We have a close time consensus
- Each disputed transaction is individually stalled:
- It has been in the final "stuck" 95% requirement for at least 2
(avMIN_ROUNDS) "inner rounds" of phaseEstablish,
- and either all of the other trusted proposers or this validator, if proposing,
have had the same vote(s) for at least 4 (avSTALLED_ROUNDS) "inner
rounds", and at least 80% of the validators (including this one, if
appropriate) agree about the vote (whether yes or no).
- If we have been in the establish phase for more than 10x the previous
consensus establish phase's time, then consensus is considered "expired",
and we will leave the round, which sends a partial validation (indicating
that the node is moving on without validating). Two restrictions avoid
prematurely exiting, or having an extended exit in extreme situations.
- The 10x time is clamped to be within a range of 15s
(ledgerMAX_CONSENSUS) to 120s (ledgerABANDON_CONSENSUS).
- If consensus has not had an opportunity to walk through all avalanche
states (defined as not going through 8 "inner rounds" of phaseEstablish),
then ConsensusState::Expired is treated as ConsensusState::No.
- When enough nodes leave the round, any remaining nodes will see they've
fallen behind, and move on, too, generally before hitting the timeout. Any
validations or partial validations sent during this time will help the
consensus process bring the nodes back together.
Levelization
Levelization is the term used to describe efforts to prevent rippled from having or creating cyclic dependencies.
rippled code is organized into directories under src/rippled (and
src/test) representing modules. The modules are intended to be
organized into "tiers" or "levels" such that a module from one level can
only include code from lower levels. Additionally, a module
in one level should never include code in an impl folder of any level
other than it's own.
Unfortunately, over time, enforcement of levelization has been inconsistent, so the current state of the code doesn't necessarily reflect these rules. Whenever possible, developers should refactor any levelization violations they find (by moving files or individual classes). At the very least, don't make things worse.
The table below summarizes the desired division of modules, based on the state of the rippled code when it was created. The levels are numbered from the bottom up with the lower level, lower numbered, more independent modules listed first, and the higher level, higher numbered modules with more dependencies listed later.
tl;dr: The modules listed first are more independent than the modules listed later.
| Level / Tier | Module(s) |
|---|---|
| 01 | ripple/beast ripple/unity |
| 02 | ripple/basics |
| 03 | ripple/json ripple/crypto |
| 04 | ripple/protocol |
| 05 | ripple/core ripple/conditions ripple/consensus ripple/resource ripple/server |
| 06 | ripple/peerfinder ripple/ledger ripple/nodestore ripple/net |
| 07 | ripple/shamap ripple/overlay |
| 08 | ripple/app |
| 09 | ripple/rpc |
| 10 | ripple/perflog |
| 11 | test/jtx test/beast test/csf |
| 12 | test/unit_test |
| 13 | test/crypto test/conditions test/json test/resource test/shamap test/peerfinder test/basics test/overlay |
| 14 | test |
| 15 | test/net test/protocol test/ledger test/consensus test/core test/server test/nodestore |
| 16 | test/rpc test/app |
(Note that test levelization is much less important and much less
strictly enforced than ripple levelization, other than the requirement
that test code should never be included in ripple code.)
Validation
The levelization.sh script takes no parameters,
reads no environment variables, and can be run from any directory,
as long as it is in the expected location in the rippled repo.
It can be run at any time from within a checked out repo, and will
do an analysis of all the #includes in
the rippled source. The only caveat is that it runs much slower
under Windows than in Linux. It hasn't yet been tested under MacOS.
It generates many files of results:
rawincludes.txt: The raw dump of the#includespaths.txt: A second dump grouping the source module to the destination module, deduped, and with frequency counts.includes/: A directory where each file represents a module and contains a list of modules and counts that the module includes.includedby/: Similar toincludes/, but the other way around. Each file represents a module and contains a list of modules and counts that include the module.loops.txt: A list of direct loops detected between modules as they actually exist, as opposed to how they are desired as described above. In a perfect repo, this file will be empty. This file is committed to the repo, and is used by the levelization Github workflow to validate that nothing changed.ordering.txt: A list showing relationships between modules where there are no loops as they actually exist, as opposed to how they are desired as described above. This file is committed to the repo, and is used by the levelization Github workflow to validate that nothing changed.levelization.ymlGithub Actions workflow to test that levelization loops haven't changed. Unfortunately, if changes are detected, it can't tell if they are improvements or not, so if you have resolved any issues or done anything else to improve levelization, runlevelization.sh, and commit the updated results.
The loops.txt and ordering.txt files relate the modules
using comparison signs, which indicate the number of times each
module is included in the other.
A > Bmeans that A should probably be at a higher level than B, because B is included in A significantly more than A is included in B. These results can be included in bothloops.txtandordering.txt. Becauseordering.txtonly includes relationships where B is not included in A at all, it will only include these types of results.A ~= Bmeans that A and B are included in each other a different number of times, but the values are so close that the script can't definitively say that one should be above the other. These results will only be included inloops.txt.A == Bmeans that A and B include each other the same number of times, so the script has no clue which should be higher. These results will only be included inloops.txt.
The committed files hide the detailed values intentionally, to prevent false alarms and merging issues, and because it's easy to get those details locally.
- Run
levelization.sh - Grep the modules in
paths.txt.- For example, if a cycle is found
A ~= B, simplygrep -w A Builds/levelization/results/paths.txt | grep -w B
- For example, if a cycle is found