Date: Tue, 21 Apr 2015 07:30:30 +0300 From: Karlis Laivins <karlis.laivins@gmail.com> To: grenville armitage <garmitage@swin.edu.au> Cc: freebsd-net@freebsd.org Subject: Re: Congestion Control Modification Message-ID: <CAF4H_7nOJP=Wy7LJSBi2PGupnMMvZu0xYeT2iYjhKDg-DPC6fw@mail.gmail.com> In-Reply-To: <5535945F.90504@swin.edu.au> References: <CAF4H_7mSGp_GZGaDBx8xq47FY1j85xLHq%2BZY1jMzprbzp%2Bg9zw@mail.gmail.com> <5535945F.90504@swin.edu.au>
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Hi, Thank you very much for such a comprehensive description of how to properly create a loadable Kernel module, this does the trick - I was able to create the module successfully, load it into Kernel and set it as the congestion control algorithm used via sysctl net.inet.tcp.cc.algorithm=new (new - the name of my test module). Best Regards, Karlis On Tue, Apr 21, 2015 at 3:05 AM, grenville armitage <garmitage@swin.edu.au> wrote: > Hi, > > > On 04/18/2015 16:59, Karlis Laivins wrote: > >> Hello, >> >> I have read an interesting publication about a proposed modification of >> TCP >> Congestion Control algorithm that would allow to improve it (the CC) by >> dynamic bandwidth estimation. The idea seems so interesting that I would >> like to try to implement it by modifying the NewReno code. >> >> Do I understand correctly that to do the above stated, I would create a >> copy of source file (in my case - cc_newreno.c) located in /usr/src/sys/ >> and rename it to, for example, cc_newreno_test.c and make changes to it? >> How would I then compile it, and how would I create a newreno_test.ko file >> that can be loaded into Kernel and tested? >> >> Thank you in advance for your answers! >> > > In case this helps shed some (probably incomplete) light, here are the > steps > I took late last year to make a modified version of NewReno: > > I start with copying the newreno module under sys/netinet/cc/cc_newreno.c > as a template. The new source file will be called newrenoVarBeta.c > > /usr/src/sys/netinet/cc % cp cc_newreno.c cc_newrenoVarBeta.c > /usr/src/sys/netinet/cc % > > Then create a modules definition based on /usr/src/sys/modules/cc/cc_cubic > (because there isn't one for newreno per se) > > /usr/src/sys/netinet/cc % cd /usr/src/sys/modules/cc > /usr/src/sys/modules/cc % mkdir cc_newrenoVarBeta > /usr/src/sys/modules/cc % cp cc_cubic/Makefile cc_newrenoVarBeta/ > /usr/src/sys/modules/cc % > > Tweak the cc_newrenoVarBeta/Makefile to say: > > KMOD= cc_newrenoVarBeta > SRCS= cc_newrenoVarBeta.c > > Made my changes to cc_newrenoVarBeta.c (including changing the module's > name from 'newreno' to something else) > > Then built/installed the new module with: > > /usr/src/sys/netinet/cc % cd /usr/src/sys/modules/cc/cc_newrenoVarBeta > /usr/src/sys/modules/cc % make clean && make && make install > [..build and install output..] > /usr/src/sys/modules/cc % > > All being well, cc_newrenoVarBeta.ko should now exist under /boot/kernel > > Then use 'kldload cc_newrenoVarBeta.ko' to load your new CC algorithm > > If all goes well, your new module will appear (with whatever name you gave > it) in the sysctl net.inet.tcp.cc.available list. Don't forget to actually > select your new module with sysctl net.inet.tcp.cc.algorithm when running > experiments. > > cheers, > gja > > > > _______________________________________________ > freebsd-net@freebsd.org mailing list > http://lists.freebsd.org/mailman/listinfo/freebsd-net > To unsubscribe, send any mail to "freebsd-net-unsubscribe@freebsd.org" >
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