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 > >
