Hi YangXin, Thanks for the update regarding the new hardware you're using. Please let us know the output from "uname -a" Network performance tuning can cause unexpected problems, so we'll try changing only the variables that will give you the largest improvements. Try adding the following to /etc/sysctl.conf and running "sysctl -p" after the changes are made; net.core.rmem_max = 1000000 net.core.wmem_max = 1000000 net.ipv4.tcp_rmem = 4096 524288 2000000 net.ipv4.tcp_wmem = 4096 65536 2000000 Afterwards, please stop and re-start the LDM. That should make a noticable improvement to performance. If for some reason it seems to make performance worse, change the vaules in /etc/sysctl.conf back to the default and re-run "sysctl -p" Let me know if that works or if it doesn't mike > Hi, Steve, > > The current platform for TIGGE Data Exchange in CMA is a IBM x3850 equipped > with 2 2-core processors and 4GB memory, > running RHEL4 update 4. As you suggested, TCP Tuning should have significant > impact to the efficiency of data transfer, > I'd like to do some test to change the important kernel parameters, see if > the performance can be improved and less > data will be lost. > > I'm sorry that I don't have a deep understanding on network performance > tuning, so I have to check some books and > materials to find out what is the critical factor to the networking system. > I've found serveral parameters that > probably have impact on TCP performance, but I'm not very sure what value is > best for LDM to work for our platform. > These parameters with the default value in our platform are as follows: > > net.ipv4.tcp_tw_reuse = 0 > net.ipv4.tcp_tw_recycle = 0 > > net.ipv4.tcp_fin_timeout = 60 > > net.ipv4.tcp_max_syn_backlog = 1024 > > net.ipv4.tcp_rmem = 4096 87380 174760 > net.core.rmem_default = 135168 > net.core.rmem_max = 135168 > > net.ipv4.tcp_wmem = 4096 16384 131072 > net.core.wmem_default = 135168 > net.core.wmem_max = 135168 > > > I believe there must be some other parameters that are important to TCP > Tuning. I only enabled > first two parameter by setting them as follows: > net.ipv4.tcp_tw_reuse = 1 > net.ipv4.tcp_tw_recycle = 1 > > and then restarted LDM. > > Is it appropriate, do I need to set any other parameters? > > Thank you. > > YangXin, > Feb 13. Ticket Details =================== Ticket ID: YSF-211129 Department: Support IDD TIGGE Priority: High Status: Closed
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