Solaris 2.5 and Solaris 2.4 patch 101945-34+ have poor TCP performance

over slow links.

Solaris 2.5 and Solaris 2.4 kernel patch 101945-34 and later have
a bug in their TCP retransmission algorithm that cause excessive
retransmissions over slow links, Sun's bug ID is #1233827.

A work around for this bug is running the following commands
at system boot, e.g., by adding them to /etc/init.d/inetinit
(values are in milliseconds):



	# DO NOT USE THESE CHANGES ON PATCHED SYSTEMS


	/usr/sbin/ndd -set /dev/tcp tcp_rexmit_interval_min 3000


	/usr/sbin/ndd -set /dev/tcp tcp_rexmit_interval_initial 3000

someone else suggested different changes, because with the above
retransmits when you do lose a packet take a long time. The following
uses a smaller value for the minimal retransmit interval but also
limits the outgoing packet size to 536 bytes, so retransmitted packets
are smaller and lost packets too.



	# DO NOT USE THESE CHANGES ON PATCHED SYSTEMS


	/usr/sbin/ndd -set /dev/tcp tcp_rexmit_interval_min 1000


	/usr/sbin/ndd -set /dev/tcp tcp_rexmit_interval_initial 3000


	/usr/sbin/ndd -set /dev/tcp tcp_mss_max 536

Patches for this bug have been released, as listed below.
You should not combine the patches with the tcp_rexmit_interval
setting listed here (patches listed are the first revisions
with the fixes; newer versions fixing more problems have been
released and can be applied instead)






	101945-42: SunOS 5.4: patch for kernel





	103169-06: SunOS 5.5: ip driver and ifconfig fixes


	103447-03: SunOS 5.5: tcp patch





	103448-03: SunOS 5.5_x86: tcp patch


	103170-06: SunOS 5.5_x86: ip driver and ifconfig fixes





	103582-01: SunOS 5.5.1: /kernel/drv/tcp patch


	103630-01: SunOS 5.5.1: ip and ifconfig patch





	103631-01: SunOS 5.5.1_x86: ip and ifconfig patch


	103581-01: SunOS 5.5.1_x86: /kernel/drv/tcp patch





	103632-01: SunOS 5.5.1_ppc: ip and ifconfig patch


	103583-01: SunOS 5.5.1_ppc: /kernel/drv/tcp patch

ASGAUR