Files
rippled/.github/scripts/levelization
Pratik Mankawde 9f92a938e5 test(telemetry): assert the nodestore_state labels and pin writer depth
The 22 metric label values on the nodestore_state gauge were asserted
nowhere, and the depthSum assertions could not tell the real
fetch_add(depth) from a fetch_add(1) that would silently zero every
derived queueing time.

Make the four observe* helpers and their ObserveFn sink public rather
than private, so the seam the header already claimed is actually
reachable. All four are static and read only their arguments, so this
exposes no object state; a friend declaration would have granted access
to every private member instead. The assertions live in the existing
Beast nodestore suite because src/test compiles into xrpld, which
contains MetricsRegistry.cpp, while xrpl_tests deliberately does not
when telemetry is enabled.

Each helper now has its exact emitted label set asserted, so a typo in
any literal fails instead of silently producing a disjoint series, and
each derived mean is asserted ABSENT on a fresh store -- a refactor to
value_or(0) would draw a believable flat zero on a latency axis and
otherwise pass everything.

Replace the concurrent write-stats test with one that forces genuine
overlap through a latch. NuDB holds one global mutex for the whole
insert and doInsert reads the depth before entering it, so a blocked
thread records a depth of at least 2; asserting depthSum strictly
exceeds insertCount therefore cannot be satisfied by a constant 1. The
old bounds admitted that bug at their floor.

Also: cover the std::nullopt branch on the two backends that exist in
every build, bound the store-duration accumulator by the wall clock,
drop four assertions that cannot fail, and correct two comments that
claimed coverage the tests do not have -- the duplicate-key test is not
the throwing path, because nudb reports key_exists without throwing,
and no test drives NodeStoreScheduler::onFetch.
2026-07-28 16:08:56 +01:00
..

Levelization

Levelization is the term used to describe efforts to prevent xrpld from having or creating cyclic dependencies.

xrpld code is organized into directories under src/xrpld, src/libxrpl (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 or detail folder of any level other than its own.

The codebase is split into two main areas:

  • libxrpl (src/libxrpl, include/xrpl): Reusable library modules with public interfaces
  • xrpld (src/xrpld): Application-specific implementation code

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 current state of the xrpld code. 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.

libxrpl Modules (Reusable Libraries)

Level / Tier Module(s)
01 xrpl/beast
02 xrpl/basics
03 xrpl/json xrpl/crypto
04 xrpl/protocol
05 xrpl/core xrpl/resource xrpl/server
06 xrpl/ledger xrpl/nodestore xrpl/net
07 xrpl/shamap xrpl/consensus

xrpld Modules (Application Implementation)

Level / Tier Module(s)
05 xrpld/conditions
06 xrpld/core xrpld/peerfinder
07 xrpld/shamap xrpld/overlay
08 xrpld/app
09 xrpld/rpc
10 xrpld/perflog

Test Modules

Level / Tier Module(s)
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 xrpl/xrpld levelization, other than the requirement that test code should never be included in xrpl or xrpld code.)

Validation

The levelization 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 xrpld 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 xrpld 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 #includes
  • paths.txt: A second dump grouping the source module to the destination module, de-duped, 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.
  • included_by/: Similar to includes/, 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.yml Github 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, run generate.py, 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 > B means 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 both loops.txt and ordering.txt. Because ordering.txtonly includes relationships where B is not included in A at all, it will only include these types of results.
  • A ~= B means 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 in loops.txt.
  • A == B means 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 in loops.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.

  1. Run generate.py
  2. Grep the modules in paths.txt.
    • For example, if a cycle is found A ~= B, simply grep -w A .github/scripts/levelization/results/paths.txt | grep -w B