Python process continuously doing epoll in introspect code

[Sachin Bansal]

root@nodeb2:/var/log/contrail# ps -aux | grep contrail-schema
contrail 8268 0.1 0.0 207996 50820 ? Sl May18 0:48 /usr/bin/python /usr/bin/contrail-schema --conf_file /etc/contrail/contrail-schema.conf --conf_file /etc/contrail/contrail-keystone-auth.conf --conf_file /etc/contrail/contrail-database.conf
root 16210 0.0 0.0 10464 932 pts/14 S+ 04:25 0:00 grep --color=auto contrail-schema
root@nodeb2:/var/log/contrail# strace -p 8268
Process 8268 attached
epoll_wait(4, {}, 64, 290) = 0
epoll_wait(4, {}, 64, 1) = 0
epoll_ctl(4, EPOLL_CTL_ADD, 12, {EPOLLIN, {u32=12, u64=176093659148}}) = -1 EEXIST (File exists)
epoll_wait(4, {}, 64, 499) = 0
epoll_ctl(4, EPOLL_CTL_ADD, 12, {EPOLLIN, {u32=12, u64=176093659148}}) = -1 EEXIST (File exists)
epoll_wait(4, {}, 64, 499) = 0
epoll_ctl(4, EPOLL_CTL_ADD, 12, {EPOLLIN, {u32=12, u64=176093659148}}) = -1 EEXIST (File exists)
epoll_wait(4, {}, 64, 499) = 0
epoll_ctl(4, EPOLL_CTL_ADD, 12, {EPOLLIN, {u32=12, u64=176093659148}}) = -1 EEXIST (File exists)
epoll_wait(4, {}, 64, 499) = 0
epoll_ctl(4, EPOLL_CTL_ADD, 12, {EPOLLIN, {u32=12, u64=176093659148}}) = -1 EEXIST (File exists)
epoll_wait(4, {}, 64, 499) = 0
epoll_ctl(4, EPOLL_CTL_ADD, 12, {EPOLLIN, {u32=12, u64=176093659148}}) = -1 EEXIST (File exists)
epoll_wait(4, {}, 64, 499) = 0
epoll_ctl(4, EPOLL_CTL_ADD, 12, {EPOLLIN, {u32=12, u64=176093659148}}) = -1 EEXIST (File exists)
epoll_wait(4, {}, 64, 113) = 0
epoll_wait(4, {}, 64, 1) = 0

[OpenContrail Admin (ci-admin-f)]

Review in progress for https://review.opencontrail.org/24716
Submitter: Sundaresan Rajangam (<email address hidden>)

[OpenContrail Admin (ci-admin-f)]

Review in progress for https://review.opencontrail.org/24718
Submitter: Sundaresan Rajangam (<email address hidden>)

[OpenContrail Admin (ci-admin-f)]

Review in progress for https://review.opencontrail.org/24716
Submitter: Sundaresan Rajangam (<email address hidden>)

[OpenContrail Admin (ci-admin-f)]

Review in progress for https://review.opencontrail.org/24718
Submitter: Sundaresan Rajangam (<email address hidden>)

[OpenContrail Admin (ci-admin-f)]

Reviewed: https://review.opencontrail.org/24716
Committed: http://github.org/Juniper/contrail-sandesh/commit/8a0b129e482cfba1801ca92b4f36dd736c2bfe41
Submitter: Zuul
Branch: master

commit 8a0b129e482cfba1801ca92b4f36dd736c2bfe41
Author: Sundaresan Rajangam <email address hidden>
Date: Thu Oct 6 00:45:15 2016 -0700

Use gevent.WSGIServer for http introspect

Presently, pysandesh uses WSGIServer defined in wsgiref.simple_server
for http introspect, whose poll_interval is 0.5 seconds by default.
The poll_interval is used to check for server shutdown. Therefore, if
the poll_interval is set to None, it requires external trigger such as
connection to the socket to wakeup the select loop. Polling reduces the
responsiveness and wastes cpu cycle. Use gevent.WSGIServer for
http introspect to avoid the polling issue.

Change-Id: Ic8cf8ec815c422be0d65e77247c67e7002bc91ad
Closes-Bug: #1584160

[OpenContrail Admin (ci-admin-f)]

Reviewed: https://review.opencontrail.org/24718
Committed: http://github.org/Juniper/contrail-sandesh/commit/d5b954786dd7fbb92e629032f3ce8f1872f43387
Submitter: Zuul
Branch: R3.1

commit d5b954786dd7fbb92e629032f3ce8f1872f43387
Author: Sundaresan Rajangam <email address hidden>
Date: Thu Oct 6 00:45:15 2016 -0700

Use gevent.WSGIServer for http introspect

Presently, pysandesh uses WSGIServer defined in wsgiref.simple_server
for http introspect, whose poll_interval is 0.5 seconds by default.
The poll_interval is used to check for server shutdown. Therefore, if
the poll_interval is set to None, it requires external trigger such as
connection to the socket to wakeup the select loop. Polling reduces the
responsiveness and wastes cpu cycle. Use gevent.WSGIServer for
http introspect to avoid the polling issue.

Change-Id: Ic8cf8ec815c422be0d65e77247c67e7002bc91ad
Closes-Bug: #1584160
(cherry picked from commit 8a0b129e482cfba1801ca92b4f36dd736c2bfe41)

[OpenContrail Admin (ci-admin-f)]

Review in progress for https://review.opencontrail.org/24773
Submitter: Sundaresan Rajangam (<email address hidden>)

[OpenContrail Admin (ci-admin-f)]

Reviewed: https://review.opencontrail.org/24773
Committed: http://github.org/Juniper/contrail-sandesh/commit/a661ecab988f136c507fdf96de2d9a2650070a54
Submitter: Zuul
Branch: R3.0

commit a661ecab988f136c507fdf96de2d9a2650070a54
Author: Sundaresan Rajangam <email address hidden>
Date: Thu Oct 6 00:45:15 2016 -0700

Use gevent.WSGIServer for http introspect

Presently, pysandesh uses WSGIServer defined in wsgiref.simple_server
for http introspect, whose poll_interval is 0.5 seconds by default.
The poll_interval is used to check for server shutdown. Therefore, if
the poll_interval is set to None, it requires external trigger such as
connection to the socket to wakeup the select loop. Polling reduces the
responsiveness and wastes cpu cycle. Use gevent.WSGIServer for
http introspect to avoid the polling issue.

Change-Id: Ic8cf8ec815c422be0d65e77247c67e7002bc91ad
Closes-Bug: #1584160
(cherry picked from commit 8a0b129e482cfba1801ca92b4f36dd736c2bfe41)