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/src/main/java/org/elasticsearch/xpack/esql/plugin/EsqlPlugin.java
* @return the settings
     */
    @Override
    public List<Setting<?>> getSettings() {
        return List.of(QUERY_RESULT_TRUNCATION_MAX_SIZE);
    }
    @Override
    public List<ActionHandler<? extends ActionRequest, ? extends ActionResponse>> getActions() {
        return List.of(
            new ActionHandler<>(EsqlQueryAction.INSTANCE, TransportEsqlQueryAction.class),
            new ActionHandler<>(EsqlStatsAction.INSTANCE, TransportEsqlStatsAction.class),
            new ActionHandler<>(XPackUsageFeatureAction.ESQL, EsqlUsageTransportAction.class),
            new ActionHandler<>(XPackInfoFeatureAction.ESQL, EsqlInfoTransportAction.class)
        );
    }
    @Override
    public List<RestHandler> getRestHandlers(
        Settings settings,
        RestController restController,
        ClusterSettings clusterSettings,
        IndexScopedSettings indexScopedSettings,
        SettingsFilter settingsFilter,
        IndexNameExpressionResolver indexNameExpressionResolver,
        Supplier<DiscoveryNodes> nodesInCluster
    ) {
        return List.of(new RestEsqlQueryAction());
    }
    @Override
    public List<NamedWriteableRegistry.Entry> getNamedWriteables() {
        return Stream.concat(