We saw a case where the recovery stats reported `recovered_bytes` greater than `length_in_bytes` for one file:

```
GET /_recovery?detailed

200 OK
...
{
  "name": "_buk.fdt",
  "length_in_bytes": 26891307173,
  "reused": false,
  "recovered_in_bytes": 35324928266,
  "recovered_from_snapshot_in_bytes": 8433621093
}
...
```

NB `35324928266 == 26891307173 + 8433621093`

This causes Elasticsearch to compute a negative value for the reserved space on the target node of this recovery, which prevents stats APIs from working. This appears to be caused by a network-level failure which triggers a retry without first cancelling an ongoing download of a different file with the same name from the snapshot repository.

---

### Workaround

Restart the target node to clear these stats.
server/src/main/java/org/elasticsearch/index/shard/IndexShard.java
}
    /**
     * Returns true if this shards is search idle
     */
    public final boolean isSearchIdle() {
        return (threadPool.relativeTimeInMillis() - lastSearcherAccess.get()) >= indexSettings.getSearchIdleAfter().getMillis();
    }
    /**
     * Returns the last timestamp the searcher was accessed. This is a relative timestamp in milliseconds.
     */
    final long getLastSearcherAccess() {
        return lastSearcherAccess.get();
    }
    /**
     * Returns true if this shard has some scheduled refresh that is pending because of search-idle.
     */
    public final boolean hasRefreshPending() {
        return pendingRefreshLocation.get() != null;
    }
    private void setRefreshPending(Engine engine) {
        final Translog.Location lastWriteLocation = engine.getTranslogLastWriteLocation();
        pendingRefreshLocation.updateAndGet(curr -> {
            if (curr == null || curr.compareTo(lastWriteLocation) <= 0) {
                return lastWriteLocation;
            } else {
                return curr;
            }
        });
    }
    private class RefreshPendingLocationListener implements ReferenceManager.RefreshListener {