On 07/20/2016 08:59 AM, Lucas Nussbaum wrote: > - there's a number of sysctl changes in /etc/sysctl.d/01_ec2.conf: > vm.swappiness = 0 > vm.dirty_ratio = 80 > vm.dirty_background_ratio = 5 > vm.dirty_expire_centisecs = 12000 > net.core.somaxconn = 1000 > net.core.netdev_max_backlog = 5000 > net.core.rmem_max = 16777216 > net.core.wmem_max = 16777216 > net.ipv4.tcp_wmem = 4096 12582912 16777216 > net.ipv4.tcp_rmem = 4096 12582912 16777216 > net.ipv4.tcp_max_syn_backlog = 8096 > net.ipv4.tcp_slow_start_after_idle = 0 > net.ipv4.tcp_tw_reuse = 1 > net.ipv4.ip_local_port_range = 10240 65535 > kernel.sysrq = 0
Look here: https://www.youtube.com/watch?v=7Cyd22kOqWc at 28:58 and 30:50 That's crazy. What Netflix presented as what seems to be custom tuning parameters specific *for they application* has been copy/past directly into the Debian EC2 "official" image, without any reasoning. It may be very good for Netflix, but very bad for the general purpose: the presentation doesn't explain this very much. We call this image "official". I'm not amused. :/ Cheers, Thomas Goirand (zigo)
