Parity details

Parity (measured after determinism)

After the determinism checks, the retained verify log of each candidate backend whose inputs can be equalized with the ptrace reference's (kvm, liteinst, sabre) is compared with the ptrace reference log. A cell's credit is the matched prefix of the two logs over the longer one, in [0, 1]; only a complete match earns 1. A cell whose reference or candidate left no deterministic golden log has no parity: it is outside the mean and the floor, never 0 credit. The inputs of dbt cannot be equalized with the ptrace reference's, so dbt is not compared and none of its cells enters any mean or floor, per backend or in the total. This panel shows the ledger's committed parity summary after checking it against the parity records it summarizes; it is separate from determinism and recomputes no credit. data/parity.json.gz publishes the committed parity carriage, whose summary text is the exact bytes its digest names, and every retained cross-backend witness in the validation history.

validate run validate-ops-tick-9af999677494-4ea4d2816eaf

Data as of: last parity record emitted 2026-10-04 09:52:42 ET; Hermit commit 9af999677494 measured; parity store at ledger commit 051dde73e48f (scorecard/parity.json, sha256 39fdb02ad300); summary written by Hermit tool commit 9af999677494.

parity: 0/297 matched; selected 297 of 297 committed; mean 0.043 over 278 measured; floor 0.043 over 281 of 297 selected (counted as 0: 3 unmeasured: no-result-row 3; excluded: 0 no golden; 16 not compared)

Committed selection: the 297 cell(s) that ci/compat-envelope/parity-cells.json selects at Hermit commit 9af999677494. This run reported all 297. It reported no cell outside it.

Mean credit 0.0432 is the credit sum 12.0081 over the 278 measured cell(s); floor credit 0.0427 is the same sum over the 281 floor cell(s): the 297 selected cell(s) less 0 with no parity (no deterministic golden) and 16 not compared. Unmeasured, record-missing and refused cells count as 0 in the floor. A cell with no parity (no deterministic golden) is outside the mean and the floor: it is never 0 credit and never a failure. The inputs of dbt cannot be equalized with the ptrace reference's, so dbt is not compared and none of its cells enters any mean or floor, per backend or in the total.

No parity (no deterministic golden): 0 cells.

Not compared (inputs cannot be equalized), outside the mean and the floor: dbt 16; TOTAL 16.

no-result-row

The reference or the candidate has no usable result row: none in the run, a retry history hermit refuses, or a row the caller rejected as invalid.

pressure-test run pressure-c470fa213ee8-20261003T180650Z

Data as of: last parity record emitted 2026-10-03 14:27:04 ET; Hermit commit c470fa213ee8 measured; parity store at ledger commit 051dde73e48f (scorecard/parity.json, sha256 39fdb02ad300); summary written by Hermit tool commit 9af999677494.

parity: not compared: 0 measured of 1 selected (inputs cannot be equalized); selected 1 of 205 committed (partial)

Committed selection: the 205 cell(s) that ci/compat-envelope/parity-cells.json selects at Hermit commit c470fa213ee8. This run reported 1 of them. The 204 with no row: c-programs/aio-refusal@kvm, c-programs/aio-refusal@liteinst, c-programs/append-pwrite@kvm, c-programs/append-pwrite@liteinst, c-programs/bind-getsockname@kvm, c-programs/bind-getsockname@liteinst, c-programs/cachestat-refusal@kvm, c-programs/cachestat-refusal@liteinst, c-programs/child-subreaper-refusal@kvm, c-programs/child-subreaper-refusal@liteinst, c-programs/close-range-fds@kvm, c-programs/close-range-fds@liteinst, c-programs/copy-file-range-refusal@kvm, c-programs/copy-file-range-refusal@liteinst, c-programs/cpu-virtualization@dbt, c-programs/cpu-virtualization@kvm, c-programs/cpu-virtualization@liteinst, c-programs/cpuid-probe@dbt, c-programs/cpuid-probe@kvm, c-programs/cpuid-probe@liteinst, and 184 more (scorecard/parity.json lists every one). It reported no cell outside it.

Mean credit is n/a: no selected cell was measured; floor credit is n/a: no cell is in the floor, which is the 1 selected cell(s) less 0 with no parity (no deterministic golden) and 1 not compared. Unmeasured, record-missing and refused cells count as 0 in the floor. A cell with no parity (no deterministic golden) is outside the mean and the floor: it is never 0 credit and never a failure. The inputs of dbt cannot be equalized with the ptrace reference's, so dbt is not compared and none of its cells enters any mean or floor, per backend or in the total.

No parity (no deterministic golden): 0 cells.

Not compared (inputs cannot be equalized), outside the mean and the floor: dbt 1; TOTAL 1.

Unmeasured: 0 cells.

No measured cell diverged.

Outside the clean headline: 0 parity rows from a dirty source tree.

Outside the clean headline: 0 parity rows that did not report their source tree state.

173 historical cross-backend parity failure(s) are kept in data/parity.json.gz and are not counted in the parity above. The retired ptrace rerun recorded them in these runs: Run 1,897; Run 229; Run 238; Run 239. They are 173 distinct cell(s) (kvm 75; liteinst 97; sabre 1) in which the candidate backend's log and the ptrace reference's log each matched its own repeat and the two logs diverged. Each is a parity failure, not a cell without parity. The legacy section above shows the same retired rerun as the ledger's parity summary keeps it, so its counts can differ from these; see https://github.com/rrnewton/hermit/issues/3301.