This may be useful: http://kerneltrap.org/mailarchive/linux-netdev/2010/4/15/6274814/thread
----- Original Message ----- > Hi Yongming, > I haven't changed the networking configuraton but I've also noticed > that once the first core is at 100% utilization the server won't > answer all ping requests anymore and has packet loss. This might be > a sign that all network traffic is handled by the first core isn't > it? > You can find a screenshot of the threading output of top here: > http://i.imgur.com/X3te2Ru.png > Best Regards > Philip > 2013/3/21 Yongming Zhao < [email protected] > > > well, due to the high network traffic, have you make the 10Ge NIC > > irq > > balanced to multiple cpu? > > > and can you show us the threading CPU usage in the top? > > > thanks > > > 在 2013-3-21，下午7:42，Philip < [email protected] > 写道： > > > > I've just upgraded to ATS 3.3.1-dev. The problem still is the > > > same: > > > http://i.imgur.com/1pHWQy7.png > > > > > > The load goes on one core. (The server is only running ATS) > > > > > > 2013/3/21 Philip < [email protected] > > > > > > > > Hi Igor, > > > > > > > > > > I am using ATS 3.2.4, Debian 6 (Squeeze) and a 3.2.13 Kernel. > > > > > > > > > > I was using the "traffic_line -r" command to see the number of > > > > origin > > > > connections growing and htop/atop to see that only one core is > > > > 100% > > > > utilized. I've already tested the following changes to the > > > > configuration: > > > > > > > > > > proxy.config.accept_threads -> 0 > > > > > > > > > > proxy.config.exec_thread.autoconfig -> 0 > > > > > > > > > > proxy.config.exec_thread.limit -> 120 > > > > > > > > > > They had no effect there is still the one core that becomes > > > > 100% > > > > utilized and turns out to be a bottleneck. > > > > > > > > > > Best Regards > > > > > > > > > > Philip > > > > > > > > > > 2013/3/21 Igor Galić < [email protected] > > > > > > > > > > > > Hi Philip, > > > > > > > > > > > > > > > Let's start with some simple data mining: > > > > > > > > > > > > > > > which version of ATS are you running? > > > > > > > > > > > > > > > What OS/Distro/version are you running it on? > > > > > > > > > > > > > > > Are you looking at stats_over_http's output to determine > > > > > what's > > > > > going > > > > > on in ATS? > > > > > > > > > > > > > > > -- i > > > > > > > > > > > > > > > > I have noticed the following strange behavior: Once the > > > > > > number > > > > > > of > > > > > > origin connections start to increase and the proxying speed > > > > > > collapses the first core is at 100% utilization while the > > > > > > others > > > > > > are > > > > > > not even close to that. It seems like the origin requests > > > > > > are > > > > > > handled by the first core only. Is this expected behavior > > > > > > that > > > > > > can > > > > > > be changed by editing the configuration or is this a bug? > > > > > > > > > > > > > > > > > > > > > 2013/3/20 Philip < [email protected] > > > > > > > > > > > > > > > > > > > > > > > Hi, > > > > > > > > > > > > > > > > > > > > > > > > > > > > I am running ATS on a pretty large server with two > > > > > > > physical > > > > > > > 6 > > > > > > > core > > > > > > > XEON CPUs and 22 raw device disks. I want to use that > > > > > > > server > > > > > > > as > > > > > > > a > > > > > > > frontend for several fileservers. It is currently > > > > > > > configured > > > > > > > to > > > > > > > be > > > > > > > infront of two file-servers. The load on the ATS server > > > > > > > is > > > > > > > pretty > > > > > > > low. About 1-4% disk utilization and 500Mbps of outgoing > > > > > > > traffic. > > > > > > > > > > > > > > > > > > > > > > > > > > > > Once I direct the traffic of the third file server > > > > > > > towards > > > > > > > ATS > > > > > > > something strange happens: > > > > > > > > > > > > > > > > > > > > > > > > > > > > - The number of origin connection increases continually. > > > > > > > > > > > > > > > > > > > > > > > > > > > > - Requests that hit ATS and are not cached are served > > > > > > > really > > > > > > > slow > > > > > > > to > > > > > > > the client (about 35 kB/s) while requests that are served > > > > > > > from > > > > > > > the > > > > > > > cache are blazingly fast. > > > > > > > > > > > > > > > > > > > > > > > > > > > > The ATS server has a dedicated 10Gbps port that is not > > > > > > > maxed > > > > > > > out, > > > > > > > no > > > > > > > CPU core is maxxed, there is no swapping, there are no > > > > > > > error > > > > > > > logs > > > > > > > and also the origin servers are not heavy utilized. It > > > > > > > feels > > > > > > > like > > > > > > > there are not enough workers to process the origin > > > > > > > requests. > > > > > > > > > > > > > > > > > > > > > > > > > > > > Is there anything I can do to check if my theory is right > > > > > > > and > > > > > > > a > > > > > > > way > > > > > > > to increase the number of origin workers? > > > > > > > > > > > > > > > > > > > > > > > > > > > > Best Regards > > > > > > > > > > > > > > > > > > > > > > > > > > > > Philip > > > > > > > > > > > > > > > > > > > > > > > > > > -- > > > > > > > > > > > > > > > Igor Galić > > > > > > > > > > > > > > > Tel: +43 (0) 664 886 22 883 > > > > > > > > > > > > > > > Mail: [email protected] > > > > > > > > > > > > > > > URL: http://brainsware.org/ > > > > > > > > > > > > > > > GPG: 6880 4155 74BD FD7C B515 2EA5 4B1D 9E08 A097 C9AE > > > > > > > > > > -- Igor Galić Tel: +43 (0) 664 886 22 883 Mail: [email protected] URL: http://brainsware.org/ GPG: 6880 4155 74BD FD7C B515 2EA5 4B1D 9E08 A097 C9AE
