From Bugzilla Helper: User-Agent: Mozilla/5.0 (X11; U; Linux i686; en-US; rv:1.4) Gecko/20030703 Epiphany/0.8.2 Description of problem: Is it a known problem that on my e1000 interface, if iptables type modules are insmodded, my outgoing traffic slows to a crawl? Modules in question: ip_nat_irc 5360 0 ip_nat_ftp 6000 0 iptable_nat 24996 4 ipt_MASQUERADE,ip_nat_irc,ip_nat_ftp ip_conntrack_irc 72340 1 ip_nat_irc ip_conntrack_ftp 73236 1 ip_nat_ftp ip_conntrack 31788 6 ipt_MASQUERADE,ip_nat_irc,ip_nat_ftp,iptable_nat,ip_conntrack_irc,ip_conntrack_ftp ip_tables 19712 2 ipt_MASQUERADE,iptable_nat Without them, I get normal 100Mbs type transfers approaching 10MB/s but with them installed, I'm getting closer to 50KB/s. If I remove the modules, things work as expected. (I need though them so my ipaq can talk to the rest of the world.) Or is this just an old software/new kernel problem? I'm running 2.6.0-0.test2.1.29smp on a dual 3.0GHz Dell 650N. Version-Release number of selected component (if applicable): kernel-smp-2.6.0-0.test2.1.29 How reproducible: Always Steps to Reproduce: 1. run 2.6 test kernel 2. install iptables modules 3. transfer any file to another system Actual Results: Transfer speeds are generally below 50KB/s. Expected Results: Transfer speeds are in the normal 8-11MB/s. Additional info: I'm just trying to figure out of this is a software (iptables) issue or a kernel issue. I can provide any other details that are needed.
Can you try loading each module separately and find out which one causes the slowdown? Also, do you have any iptables rules installed?
ip_conntrack is what does it: [tjb@wintermute incoming]# modprobe ip_conntrack [tjb@wintermute incoming]# time scp radiohead.mov katratzi:/tmp root@katratzi's password: radiohead.mov 1% 836KB 49.1KB/s 19:50 ETAKilled by signal 2. 0.000u 0.007s 0:22.98 0.0% 0+0k 0+0io 224pf+0w [tjb@wintermute incoming]# rmmod ip_conntrack [tjb@wintermute incoming]# time scp radiohead.mov katratzi:/tmp root@katratzi's password: radiohead.mov 100% 57MB 8.3MB/s 00:06 1.408u 0.297s 0:12.08 13.9% 0+0k 0+0io 623pf+0w [tjb@wintermute incoming]#
This also happens with 2.6.0-0.test3.1.31smp.
2.6.0-0.test4.1.32smp too.
I just tried this on 2.6.0-0.test5.1.45smp and the problem is still there to some degree. When transfering a 93MB file, the first 2.5MB or so is transfered at about 50KB/s and then suddenly the transfer speed increases to about 8MB/s. The total transfer time for a 93MB file averages about 1 minute with the ip_conntrack installed and 11 seconds after removing it.
If it happens with 2.6.x, please report this to the netfilter list (netfilter.org). They play with this stuff every day, so they're likely to figure out what the problem is several orders of magnitude faster than I could.
Fixed in recent kernels including kernel-smp-2.6.5-1.358.