Reviewed: https://review.openstack.org/416400 Committed: https://git.openstack.org/cgit/openstack/neutron/commit/?id=9a022e7d7b85b7c21cf26698fe59c818c4577194 Submitter: Jenkins Branch: master
commit 9a022e7d7b85b7c21cf26698fe59c818c4577194 Author: Kevin Benton <ke...@benton.pub> Date: Tue Jan 3 18:10:36 2017 -0800 Reduce IP link show calls for SR-IOV scan loop The device scanning logic was calling 'ip link show' for every vf_index on the system, which was taking an excessive amount of time an CPU cycles on very dense SR-IOV servers (>64 interfaces). This was being executed every 2 seconds so it would cause the agent to take a large percentage of the CPU time. This patch adjusts the logic to use two 'ip link show' commands for checking all of the operations in a single get_assigned_devices_info call. Closes-Bug: #1653880 Change-Id: I361caaf7f70580ee8c7b48a4a9c9477bdefd8b4b ** Changed in: neutron Status: In Progress => Fix Released -- You received this bug notification because you are a member of Yahoo! Engineering Team, which is subscribed to neutron. https://bugs.launchpad.net/bugs/1653880 Title: sr-iov device scanning takes significant time Status in neutron: Fix Released Bug description: The excessive calls to 'ip link show' can consume significant amounts of CPU cycles on every scan_devices iteration on densely packed SR-IOV systems. Snip from https://bugs.launchpad.net/mos/+bug/1653131 : On a node with SR-IOV interfaces neutron-sriov-agent seems to call 'ip link show' every 2 second for each interface. This leads to CPU utilization up to 60+% (I've seen 32% for neutron-rootwrap and 32% for neutron-sriov-nic-agent) Since output of `ip link show' is the same for all interfaces, it is enough to call it only once per 2 sec interval root@node-7:~# grep '15:10:' /var/log/neutron/neutron-sriov-agent.log | grep "'ip', 'link', 'show'" | wc -l 5783 To manage notifications about this bug go to: https://bugs.launchpad.net/neutron/+bug/1653880/+subscriptions -- Mailing list: https://launchpad.net/~yahoo-eng-team Post to : yahoo-eng-team@lists.launchpad.net Unsubscribe : https://launchpad.net/~yahoo-eng-team More help : https://help.launchpad.net/ListHelp