Change in vdsm[master]: migration: added support for convergance schedule

Francesco Romani has posted comments on this change.

Change subject: migration: added support for convergance schedule
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Patch Set 4:

(2 comments)

https://gerrit.ovirt.org/#/c/46940/4/vdsm/virt/migration.py
File vdsm/virt/migration.py:

Line 138:         self._do_perform_migration = _perform_with_downtime_thread
Line 139:         if kwargs.has_key('convergenceSchedule'):
Line 140:             # example convergence schedule
Line 141:             # "[(1, ('setDowntime', (10))), (4, ('abort', ()))]"
Line 142:             schedule = literal_eval(kwargs.get('convergenceSchedule'))
> Ugh, this is thought to swallow. Can't we have the convergenceSchedule expr

Proposal:

This is pretty similar and it is valid JSON:

'[[1, ["setDowntime", [10]]], [4, ["abort", []]]]'

can we use this format instead? It is also valid python, modulo the choice of quotes.

If we use this, we can have:

schedule = json.loads(kwargs.get('convergenceSchedule))
Line 143:             self._do_perform_migration = \
Line 144:                 _perform_with_conv_schedule_monitor_thread
Line 145: 
Line 146:         self._convergenceSchedule = map(ConvergenceItem._make,

Line 145: 
Line 146:         self._convergenceSchedule = map(ConvergenceItem._make,
Line 147:                                         [(s[0],
Line 148:                                           map(ConvergenceAction._make,
Line 149:                                               s[1:])[0]) for s in schedule])
> this is hard to read, we need to simplify this. But first let's agree about

whatever format we choose, we can also write:

self._convergence_schedule = [
     ConvergenceItem(lim, ConvergenceAction(act, params)) 
     for lim, (act, params) in schedule
  ]

which is IMHO bettter
Line 150: 
Line 151:         self.log.debug('convergence schedule set to: ' + str(self._convergenceSchedule))
Line 152: 
Line 153: