From 56096be8b6e3f67e3bdce25bee73d0fc0534b0d5 Mon Sep 17 00:00:00 2001 From: Adam Ierymenko Date: Wed, 6 Apr 2016 16:28:40 -0700 Subject: [PATCH] Tweak new RX queue algorithm to "expire" old entries to prevent always needing to traverse the whole queue array. --- node/Constants.hpp | 5 +++++ node/Switch.cpp | 4 ++-- node/Switch.hpp | 4 +++- 3 files changed, 10 insertions(+), 3 deletions(-) diff --git a/node/Constants.hpp b/node/Constants.hpp index c9356da02..6c44a8dc2 100644 --- a/node/Constants.hpp +++ b/node/Constants.hpp @@ -169,6 +169,11 @@ */ #define ZT_RX_QUEUE_SIZE 64 +/** + * RX queue entries older than this do not "exist" + */ +#define ZT_RX_QUEUE_EXPIRE 4000 + /** * Length of secret key in bytes -- 256-bit -- do not change */ diff --git a/node/Switch.cpp b/node/Switch.cpp index 890a94652..968d1a4a8 100644 --- a/node/Switch.cpp +++ b/node/Switch.cpp @@ -138,7 +138,7 @@ void Switch::onRemotePacket(const InetAddress &localAddr,const InetAddress &from // seeing a Packet::Fragment? Mutex::Lock _l(_rxQueue_m); - RXQueueEntry *const rq = _findRXQueueEntry(fragmentPacketId); + RXQueueEntry *const rq = _findRXQueueEntry(now,fragmentPacketId); if ((!rq->timestamp)||(rq->packetId != fragmentPacketId)) { // No packet found, so we received a fragment without its head. @@ -241,7 +241,7 @@ void Switch::onRemotePacket(const InetAddress &localAddr,const InetAddress &from // Packet is the head of a fragmented packet series Mutex::Lock _l(_rxQueue_m); - RXQueueEntry *const rq = _findRXQueueEntry(packetId); + RXQueueEntry *const rq = _findRXQueueEntry(now,packetId); if ((!rq->timestamp)||(rq->packetId != packetId)) { // If we have no other fragments yet, create an entry and save the head diff --git a/node/Switch.hpp b/node/Switch.hpp index 219bfb416..ce4f00a16 100644 --- a/node/Switch.hpp +++ b/node/Switch.hpp @@ -184,7 +184,7 @@ private: /* Returns the matching or oldest entry. Caller must check timestamp and * packet ID to determine which. */ - inline RXQueueEntry *_findRXQueueEntry(uint64_t packetId) + inline RXQueueEntry *_findRXQueueEntry(uint64_t now,uint64_t packetId) { RXQueueEntry *rq; RXQueueEntry *oldest = &(_rxQueue[ZT_RX_QUEUE_SIZE - 1]); @@ -193,6 +193,8 @@ private: rq = &(_rxQueue[--i]); if ((rq->packetId == packetId)&&(rq->timestamp)) return rq; + if ((now - rq->timestamp) >= ZT_RX_QUEUE_EXPIRE) + rq->timestamp = 0; if (rq->timestamp < oldest->timestamp) oldest = rq; }