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author | bms <bms@FreeBSD.org> | 2009-03-09 17:53:05 +0000 |
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committer | bms <bms@FreeBSD.org> | 2009-03-09 17:53:05 +0000 |
commit | 71233409ea6a2f4d751847c05e7aad9375278d94 (patch) | |
tree | 3d95180b6661648cd67dba62e6daefc7c8661793 /UPDATING | |
parent | 2173e9258f5b3400a58f42bd91fd01c1efc4441d (diff) | |
download | FreeBSD-src-71233409ea6a2f4d751847c05e7aad9375278d94.zip FreeBSD-src-71233409ea6a2f4d751847c05e7aad9375278d94.tar.gz |
Merge IGMPv3 and Source-Specific Multicast (SSM) to the FreeBSD
IPv4 stack.
Diffs are minimized against p4.
PCS has been used for some protocol verification, more widespread
testing of recorded sources in Group-and-Source queries is needed.
sizeof(struct igmpstat) has changed.
__FreeBSD_version is bumped to 800070.
Diffstat (limited to 'UPDATING')
-rw-r--r-- | UPDATING | 39 |
1 files changed, 39 insertions, 0 deletions
@@ -23,6 +23,45 @@ NOTE TO PEOPLE WHO THINK THAT FreeBSD 8.x IS SLOW: ln -s aj /etc/malloc.conf.) 20090309: + IGMPv3 and Source-Specific Multicast (SSM) have been merged + to the IPv4 stack. VIMAGE hooks are in but not yet used. + + For kernel developers, the most important changes are that the + ip_output() and ip_input() paths no longer take the IN_MULTI_LOCK(), + and this lock has been downgraded to a non-recursive mutex. + + Transport protocols (UDP, Raw IP) are now responsible for filtering + inbound multicast traffic according to group membership and source + filters. The imo_multicast_filter() KPI exists for this purpose. + Transports which do not use multicast (SCTP, TCP) already reject + multicast by default. Forwarding and receive performance may improve + as a mutex acquisition is no longer needed in the ip_input() + low-level input path. in_addmulti() and in_delmulti() are shimmed + to new KPIs which exist to support SSM in-kernel. + + For application developers, it is recommended that loopback of + multicast datagrams be disabled for best performance, as this + will still cause the lock to be taken for each looped-back + datagram transmission. The net.inet.ip.mcast.loop sysctl may + be tuned to 0 to disable loopback by default; it defaults to 1 + to preserve the existing behaviour. + + For systems administrators, to obtain best performance with + multicast reception and multiple groups, it is always recommended + that a card with a suitably precise hash filter is used. Hash + collisions will still result in the lock being taken within the + transport protocol input path to check group membership. + + If deploying FreeBSD in an environment with IGMP snooping switches, + it is recommended that the net.inet.igmp.sendlocal sysctl remain + enabled; this forces 224.0.0.0/24 group membership to be announced + via IGMP. + + The size of 'struct igmpstat' has changed; netstat needs to be + recompiled to reflect this. + Bump __FreeBSD_version to 800070. + +20090309: libusb20.so.1 is now installed as libusb.so.1 and the ports system updated to use it. This requires a buildworld/installworld in order to update the library and dependencies (usbconfig, etc). Its advisable to |