Public bug reported: With wsgi_default_pool_size=100[1], if the keepalived state change server gets 100 requests at the same time, while processing the requests heavy load is seen on cpu, making the network node unresponsive. For each request, keepalived state change server spawns a new meta data proxy process(i.e neutron-ns-metadata-proxy). During heavy cpu load, with "top" command, I can see many metadata proxy processes in "running" state at same time(see the attachment).
When wsgi_default_pool_size=8, I see state change server spawning 8 metadata proxy processes at a time("top" command shows 8 meta data proxy processes in "running" state at a time), cpu load is less and metadata proxy processes(for example, 100) spawned for all requests without failures. We can keep wsgi_default_pool_size=100 for neutron API server, and use seperate configuration for UnixDomainWSGIServer(for example CONF.unix_domain_wsgi_default_pool_size). neutron/agent/linux/utils.py class UnixDomainWSGIServer(wsgi.Server): def _run(self, application, socket): """Start a WSGI service in a new green thread.""" logger = logging.getLogger('eventlet.wsgi.server') eventlet.wsgi.server(socket, application, max_size=CONF.unix_domain_wsgi_default_pool_size, protocol=UnixDomainHttpProtocol, log=logger) [1] https://github.com/openstack/neutron/commit/9d573387f1e33ce85269d3ed9be501717eed4807 ** Affects: neutron Importance: Undecided Assignee: venkata anil (anil-venkata) Status: New ** Tags: l3-ha ** Attachment added: "top.gif" https://bugs.launchpad.net/bugs/1581580/+attachment/4662237/+files/top.gif ** Changed in: neutron Assignee: (unassigned) => venkata anil (anil-venkata) -- You received this bug notification because you are a member of Yahoo! Engineering Team, which is subscribed to neutron. https://bugs.launchpad.net/bugs/1581580 Title: Heavy cpu load seen when keepalived state change server gets wsi_default_pool_size requests at same time Status in neutron: New Bug description: With wsgi_default_pool_size=100[1], if the keepalived state change server gets 100 requests at the same time, while processing the requests heavy load is seen on cpu, making the network node unresponsive. For each request, keepalived state change server spawns a new meta data proxy process(i.e neutron-ns-metadata-proxy). During heavy cpu load, with "top" command, I can see many metadata proxy processes in "running" state at same time(see the attachment). When wsgi_default_pool_size=8, I see state change server spawning 8 metadata proxy processes at a time("top" command shows 8 meta data proxy processes in "running" state at a time), cpu load is less and metadata proxy processes(for example, 100) spawned for all requests without failures. We can keep wsgi_default_pool_size=100 for neutron API server, and use seperate configuration for UnixDomainWSGIServer(for example CONF.unix_domain_wsgi_default_pool_size). neutron/agent/linux/utils.py class UnixDomainWSGIServer(wsgi.Server): def _run(self, application, socket): """Start a WSGI service in a new green thread.""" logger = logging.getLogger('eventlet.wsgi.server') eventlet.wsgi.server(socket, application, max_size=CONF.unix_domain_wsgi_default_pool_size, protocol=UnixDomainHttpProtocol, log=logger) [1] https://github.com/openstack/neutron/commit/9d573387f1e33ce85269d3ed9be501717eed4807 To manage notifications about this bug go to: https://bugs.launchpad.net/neutron/+bug/1581580/+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