Conversation
Gemma 4's `use_double_wide_mlp=True` widens gate/up/down_proj to 2× base `intermediate_size` on KV-shared layers. On gemma-4-e2b-it (35 layers, last 20 shared), layers 15–34 have `intermediate=12288`, layers 0–14 have 6144. Crown-scan defaults to `(3n/5)=21` and lands on a double-wide layer, so the rank-1 edit hit `intermediate-size mismatch in captured keys` against the config-wide base size. Adds `ModelArchitecture::intermediate_size_for_layer(layer) -> usize` (default = `config.intermediate_size`, mirroring `head_dim_for_layer`). `Gemma4Arch` overrides by reusing the precomputed `kv_sources` set — one source of truth for KV-shared-layer membership. Thread the per-layer lookup through: - `edit_py.rs`: compute `intermediate` after `chosen_layer` is picked. - `edit_cmd.rs`: same for the CLI path. - `memit.rs`: `ffn_dim` now per-layer; `run_memit` already solves per layer, so covariances remain correctly sized across mixed layers. Parse `use_double_wide_mlp` in `detect.rs`; add to `ModelConfig`. Tests (in `detect.rs`): - `test_detect_gemma4_e2b`: asserts 6144 on L0/L14, 12288 on L15/L21/L34 — matches the actual HF tensor shapes verified in the Colab repl. - `test_gemma4_31b_no_double_wide`: 31B lacks the flag → base everywhere. - `test_non_gemma4_intermediate_default`: Llama returns base for all layers via the default trait impl. The bare `weights.intermediate_size` field is left as "base" for display / metadata call sites (demos, patch-print, vindex stats). Patch file-format unchanged: `compute_rank1` / `compute_dense` already derive `intermediate_size` from the runtime tensor, so new patches for double-wide layers store 12288 correctly without a version bump. Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>
Three fixes for larql-server session management: 1. **Bug 1 — write-lock starvation on INFER**: switched sessions_blocking_write → sessions_blocking_read on the INFER path; made last_accessed AtomicU64 so touch() takes &self. 2. **Bug 2 — rebuild_overrides leak**: added base.down_overrides.clear() + base.up_overrides.clear() before replaying patches on remove. 3. **Bug 3 — blocking_read inside async**: pre-acquire base vindex before entering write lock in apply_patch to avoid tokio panic. All three gates verified: T2 concurrent PASS, T3 global-leak PASS, T4 throughput PASS (mixed p50 0.94× same-session), T5 revert PASS.
Three gates run on every push/PR (T2=concurrent, T3=global-leak, T5=revert). Requires HARNESS_REPO_TOKEN secret (fine-grained PAT, Contents:read on Divinci-AI/larql-isolation-harness). testdata/tiny-vindex is a reproducible 5 MB synthetic vindex generated by generate.py (seed=42, 8 layers, hidden=128) — no real model weights needed. Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>
This file contains hidden or bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
Sign up for free
to join this conversation on GitHub.
Already have an account?
Sign in to comment
1 participant
Add this suggestion to a batch that can be applied as a single commit.This suggestion is invalid because no changes were made to the code.Suggestions cannot be applied while the pull request is closed.Suggestions cannot be applied while viewing a subset of changes.Only one suggestion per line can be applied in a batch.Add this suggestion to a batch that can be applied as a single commit.Applying suggestions on deleted lines is not supported.You must change the existing code in this line in order to create a valid suggestion.Outdated suggestions cannot be applied.This suggestion has been applied or marked resolved.Suggestions cannot be applied from pending reviews.Suggestions cannot be applied on multi-line comments.Suggestions cannot be applied while the pull request is queued to merge.Suggestion cannot be applied right now. Please check back later.
Summary
per_layer_intermediate_size)Notes
CI is pending a billing unblock on the Actions account — all three gates were verified locally against the synthetic vindex (T2: 100 iterations PASS, T5: PASS). Will auto-confirm on next push once billing clears.
🤖 Generated with Claude Code