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Jeremy RuppelandSteven Masley
51a9aa1bfc
`POST /api/v2/authcheck` evaluated every check with a full policy evaluation in a serial loop. A subject in many organizations (100+) produced hundreds of full evaluations, taking seconds on a cold cache (DEVEX-608). Group the checks by `(action, resource type)` and authorize each group with the existing `rbac.Filter`, which amortizes a single partial evaluation across the group once it is large enough. Each check is wrapped in a small value struct that carries its response key, so `Filter`'s returned subset maps back to keys by reading a field rather than relying on element identity. `Filter` now takes an explicit `prepareThreshold`; existing callers pass the new `rbac.DefaultFilterThreshold` (10), and `checkAuthorization` passes 50, above the ~35-group crossover measured for this workload, so subjects with few objects of a given type keep the per-object path and cannot regress. ## Stacking This is stacked on top of #27244. `Filter` runs `Prepare` (partial evaluation), and those residuals are only compact once #27244's set-membership residuals land. On plain `main` the existing O(N) residual fanout means batching can regress at high org counts, so this change should land with or after #27244. <details> <summary>Decision log</summary> ### Bottleneck - `site/src/modules/permissions/organizations.ts` defines ~14 permission checks per org; `organizationsPermissions()` flattens them across all orgs into one `POST /api/v2/authcheck`. A 100-org request is ~1400 checks. - `checkAuthorization` looped serially, calling `Authorizer.Authorize` (full eval) once per check. - The endpoint's `maxFetch = 10` only caps checks that carry a `resource_id`, not total checks, so it does not bound this workload. ### Approach - Group checks by `(action, resource type)` and run each group through `rbac.Filter`, which does one partial evaluation (`Prepare`) and reuses it across the group. - Carry the response key as data in a small value struct implementing `RBACObject()`, so allowed results map back to keys without pointer identity: ```go type authorizeCheck struct { key string object rbac.Object } func (c authorizeCheck) RBACObject() rbac.Object { return c.object } ``` - `Filter` takes a required `prepareThreshold int` (no functional options). Generic callers pass `rbac.DefaultFilterThreshold = 10`; `/authcheck` passes 50 because the measured crossover for this workload is ~35 groups. ### Alternatives rejected - **Bounded `errgroup` parallelism**: reduced wall time at high org counts but not aggregate work (allocations flat). Discarded in favor of reducing work via partial evaluation. - **Symmetric-deny Rego simplification** (on the #27244 branch): replacing the known-org deny-fold with symmetric `org := -1` / `scope_org := -1` rules failed existing SQL-compile tests. A `-1` known-org vote gated by `not org = -1` produces a negated membership test over the unknown org id, which OPA emits as an unconvertible support rule. #27244's fold (`member_allow - org_deny`, a positive set-difference membership test) is therefore load-bearing, not incidental. </details> --- Authored with Coder Agents. --------- Co-authored-by: Steven Masley <Emyrk@users.noreply.github.com>