Hi ManKeer,

If the delays involve only a subset of the clients and then we can exclude a general problem affecting the whole server you should look for the "NIO write queue" and "NIO write queue wait" metrics in the MonitorText logs.
When these metrics show high values, and are constantly growing, it means that a part of the client sessions can not cope with the frequency of incoming real-time messages may be due to poor connectivity conditions or very slow devices, and the server accumulates delays in sending messages to them.

Below an example of MonitorText log line with the mentioned metrics in evidence:

"MonitorText|Timer-0 |Total threads = 460, Total heap = 231735296 (free = 16710304), Sessions = 3148 (max = 3175), New sessions = [+16, -12], Connections = 3473 (max = 3575), New connections = [+52, -37], In-pool threads = 128, Active threads = 4, Available threads = 124, Queued tasks = 0, Pool queue wait = 0, NIO write queue = 64, NIO write queue wait = 2457239, NIO write selectors = 32, NIO total selectors = 128, Subscribed items = 47 (for 25363 subscriptions), Inbound throughput = 116.3 updates/s (pre-filtered = 116.3), Outbound throughput = 13418.99 updates/s (6259.6 kbit/s, max = 11693.98), Lost updates = 0 (total = 0), Total bytes sent = 9265303321, Client messages throughput = 0 msgs/s (0 kbit/s, max = 0), Total messages handled = 0, Extra sleep = 0, Notify delay = 0 "

In any case if the size of the logs is not very big you can send them to support@lightstreamer.com

Regards,
Giuseppe