Searching a large number of unavailable shards through e.g. the `*` pattern while a large cluster is recovering from a full restart or so, leads to extremely large responses containing an exception for each shard.


![](https://user-images.githubusercontent.com/6490959/193701098-868888bc-cdc7-4104-a32a-d9c84d74aef2.png)

This example shows a 375M on heap response for ~25k unavailable shards being returned. Over the wire, this serialises with a similar size and we'd have 700M+ peak heap usage for a search request when the valid search response in a green cluster might be much smaller than this.
It seems to me that we could mostly resolve this by not returning the stack trace in this specific case of the shard not available exception (it doesn't seem valuable for users and we made a similar fix around unavailable shards in snapshots state responses)? 
server/src/main/java/org/elasticsearch/action/search/AbstractSearchAsyncAction.java
}
                        }
                    });
                } catch (final Exception e) {
                    try {
                        /*
                         * It is possible to run into connection exceptions here because we are getting the connection early and might
                         * run into nodes that are not connected. In this case, on shard failure will move us to the next shard copy.
                         */
                        fork(() -> onShardFailure(shardIndex, shard, shardIt, e));
                    } finally {
                        executeNext(pendingExecutions, thread);
                    }
                }
            };
            if (throttleConcurrentRequests) {
                pendingExecutions.tryRun(r);
            } else {
                r.run();
            }
        }
    }
    /**
     * Sends the request to the actual shard.
     * @param shardIt the shards iterator
     * @param shard the shard routing to send the request for
     * @param listener the listener to notify on response
     */
    protected abstract void executePhaseOnShard(
        SearchShardIterator shardIt,