new: configurable UDP receive buffer (SO_RCVBUF), default 1 MB#195
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The UDP transport left the socket receive buffer at the OS default (64 KB on Windows), so a burst of incoming messages could overflow it and the OS silently dropped packets - e.g. a fast run of event notifications where the handler is slow (#132). Set it to 1 MB by default and expose a ReceiveBufferSize property that can be changed at any time, including after Start() (applied to the live socket). Over-requesting is honored on Windows and clamped to net.core.rmem_max on Linux/Raspberry Pi - never fatal, so no per-OS handling is needed.
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Follow-up to the #132 investigation. The UDP transport never set the socket receive buffer, so it used the OS default (64 KB on Windows). Under a burst of incoming messages — e.g. event notifications delivered faster than a slow
OnEventNotifyhandler drains them — the buffer overflows and the OS silently drops packets. That is the "some notifications are missed" in #132.Change
ReceiveBufferSizeproperty that can be changed at any time, including afterStart()— it is applied to the live socket(s) immediately.Why 1 MB works on PC and Raspberry Pi
Over-requesting
SO_RCVBUFis never fatal:net.core.rmem_max(~208 KB default) — no error, only the clamped amount is allocated (trivial even on a 512 MB Pi). To go higher you raisenet.core.rmem_maxvia sysctl.Verified
ReceiveBufferSizereads back1048576by default and successfully changes to 4 MB afterStart()(applied to the live socket).Note: this raises the burst threshold; the deeper guidance for #132 (return fast from
OnEventNotify, offload heavy work) still stands.