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[TIGGE #YSF-211129]: TCP tuning for TIGGE tuning



Hi YangXin,

Would it be possible for me to have access to an account on your tigge system 
for testing?  Ideally, it would be
useful for me to have an account on all three tigge nodes exchanging data.  I 
can make good progress with a user
level account, but the ability to su/sudo root would also be helpful.

If you know or could inquire about the network connections (bandwidth) this 
machine has to your network and to
the external network, that information would be valuable?

For now, it should be safe to leave the changed kernel variables in place.

mike

> Hi, Mike,
> 
> This morning, I changed  values for the four OS Parameters as you 
> recommended. Having observed the receiving of data 
> for about ten hours, nothing was found shows performance reduction or 
> improving. Maybe only when the system load or 
> network load reach a certain point, the setting for these parameters would 
> become an critical issue. Do I need to 
> change them back to defaults?
> 
> The output from "uname -a" is as follows:
> 
> Linux tgn01 2.6.9-42.ELsmp #1 SMP Wed Jul 12 23:32:02 EDT 2006 x86_64 x86_64 
> x86_64 GNU/Linux
> 
> Thank you.
> 
> Best Regards,
> YangXin,
> Feb 14.
> 
> 
> 
> ======= 2007-02-14 02:23:40 ÄúÔÚÀÐÅÖÐеÀº=======
> 
> >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
> >
> 
> = = = = = = = = = = = = = = = = = = = =
> 
> 
> ¡¡¡¡¡¡¡¡¡¡¡¡¡¡¡¡ÖÂ
> Àñ£¡
> 
> 
> ¡¡¡¡¡¡¡¡¡¡¡¡¡¡¡¡yangxin
> address@hidden
> ¡¡¡¡¡¡¡¡¡¡¡¡¡¡¡¡¡¡¡¡2007-02-14
> 
> 


Ticket Details
===================
Ticket ID: YSF-211129
Department: Support IDD TIGGE
Priority: Emergency
Status: Closed


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