Performing any long running task or CPU intensive work on transport_worker threads is problematic. This is typically very bad for cluster stability.

This issue has been filed to examine the usage of transport_worked threads by ESQL, with the intention of "offloading" as much as possible, including deserialising large(ish) amounts of data.
x-pack/plugin/esql/compute/src/main/java/org/elasticsearch/compute/operator/exchange/ExchangeService.java
if (elapsed > maxInterval.millis()) {
                    finishSinkHandler(
                        e.getKey(),
                        new ElasticsearchTimeoutException(
                            "Exchange sink {} has been inactive for {}",
                            e.getKey(),
                            TimeValue.timeValueMillis(elapsed)
                        )
                    );
                }
            }
        }
    }
    /**
     * Creates a new {@link RemoteSink} that fetches pages from an exchange sink located on the remote node.
     *
     * @param parentTask       the parent task that initialized the ESQL request
     * @param exchangeId       the exchange ID
     * @param transportService the transport service
     * @param remoteNode       the node where the remote exchange sink is located
     */
    public RemoteSink newRemoteSink(Task parentTask, String exchangeId, TransportService transportService, DiscoveryNode remoteNode) {
        return new TransportRemoteSink(transportService, remoteNode, parentTask, exchangeId);
    }
    record TransportRemoteSink(TransportService transportService, DiscoveryNode node, Task parentTask, String exchangeId)
        implements
            RemoteSink {
        @Override
        public void fetchPageAsync(boolean allSourcesFinished, ActionListener<ExchangeResponse> listener) {
            transportService.sendChildRequest(