Comment 9 for bug 1589014

Reviewed: https://review.opencontrail.org/21028
Committed: http://github.org/Juniper/contrail-controller/commit/7d6cd7b34e579bbc2c4019e2c4d76679eee0102f
Submitter: Zuul
Branch: master

commit 7d6cd7b34e579bbc2c4019e2c4d76679eee0102f
Author: Ranjeet R <email address hidden>
Date: Wed Jun 8 16:29:49 2016 -0700

Fixes: API Server Performance Optimization Placeholder bug

Test setup
20000 VMs 20000 VMIs 20000 Instance IPs
API server startup takes 6 minutes 7 seconds to start

This commit has two improvements -
1. In Dbe_resync, we yield the greenlet to make sure that
Zookeeper heartbeats are working. But during startup, ZK
heartbeats are not relevant. Improves perf from 6:07 to 4:35.

2. In IFMAP publish call, the cache organization was not
efficient. We use the following schema now.

id_to_metas = { 'id': //id1
{'meta_name':
{'': prop_value} or // If the meta is a prop
{id2:ref_value} //If the meta is a ref
changes in object_delete/update to take care of this organization.
Improves perf from 4:35 to 3:35
Updating UTs to reflect this/

3. Eduoard's change of using ujson instead of simplejson in
https://review.opencontrail.org/21049 brings down the time to
another 20 seconds, 3:35 to 315

4. Not sending the VM's UVE trace during startup
is saving another 25 seconds
3:15 to 2:50

Change-Id: I473ed25b09f7b59e82e2bc77e2ce1f89d9be0661
Partial-Bug: 1589014