Files
ragflow/rag/graphrag
OSHA-B b0e6007131 perf: batch-embed entity/edge names in set_graph() to fix stall on large graphs (#16205) (#16472)
## Problem

When building or updating a knowledge graph with a large number of
entities and edges, `set_graph()` in `rag/graphrag/utils.py` creates one
`asyncio` task per entity and one per edge, each calling
`embd_mdl.encode([single_name])` — a single-item HTTP request to the
embedding server.

For a graph with 17,000+ nodes and edges (real case reported in #16205),
this generates **34,000+ individual embedding API round-trips** instead
of ~266 batched calls at the default `_INSERT_BULK_SIZE=128`. The
asyncio gather over thousands of tasks makes the embedding server the
bottleneck; under load, a single slow/failed call aborts all remaining
tasks, causing the pipeline to stall and never complete.

Closes #16205. Related: #15921.

## Root Cause

```python
# Before (in set_graph, node loop):
tasks = [asyncio.create_task(graph_node_to_chunk(n, ...)) for n in nodes]
# Each task calls embd_mdl.encode([single_name]) — 1 HTTP call per node
```

`graph_node_to_chunk` checks the embed cache first, but the cache is
cold on first build, so every task makes a live API call.

## Fix

Pre-warm the embedding cache with batched calls before spawning tasks.
Each batch pre-warm calls `embd_mdl.encode(batch_of_128)` once,
populating the cache. Then every individual task hits the cache and
makes zero embedding API calls.

- Only encodes names not already in cache (no-op on warm cache / small
incremental updates)
- Uses existing project idioms: `thread_pool_exec`, `chat_limiter`,
`_INSERT_BULK_SIZE`, `get_embed_cache`, `set_embed_cache`
- Mirrors the `ENABLE_TIMEOUT_ASSERTION` timeout pattern from
`graph_node_to_chunk`
- Zero behavior change: per-task encode logic remains as a correct
fallback

## Result

| Graph size | Before | After |
|---|---|---|
| 17,576 edges | ~17,576 embedding calls → stall | ~138 batched calls |
| 17,509 nodes | ~17,509 embedding calls → stall | ~137 batched calls |
| **Total** | **~35,000 calls** | **~275 calls** |

---------

Co-authored-by: Oti_B <oti@mac.speedport.ip>
2026-07-01 20:45:20 +08:00
..
2026-05-29 17:39:41 +08:00
2026-01-29 14:23:26 +08:00