Commit Graph

4 Commits

Author SHA1 Message Date
Lang Martin ac7c39d3d3
Delayed evaluations for `stop_after_client_disconnect` can cause unwanted extra followup evaluations around job garbage collection (#8099)
* client/heartbeatstop: reversed time condition for startup grace

* scheduler/generic_sched: use `delayInstead` to avoid a loop

Without protecting the loop that creates followUpEvals, a delayed eval
is allowed to create an immediate subsequent delayed eval. For both
`stop_after_client_disconnect` and the `reschedule` block, a delayed
eval should always produce some immediate result (running or blocked)
and then only after the outcome of that eval produce a second delayed
eval.

* scheduler/reconcile: lostLater are different than delayedReschedules

Just slightly. `lostLater` allocs should be used to create batched
evaluations, but `handleDelayedReschedules` assumes that the
allocations are in the untainted set. When it creates the in-place
updates to those allocations at the end, it causes the allocation to
be treated as running over in the planner, which causes the initial
`stop_after_client_disconnect` evaluation to be retried by the worker.
2020-06-03 09:48:38 -04:00
Lang Martin d3c4700cd3
server: stop after client disconnect (#7939)
* jobspec, api: add stop_after_client_disconnect

* nomad/state/state_store: error message typo

* structs: alloc methods to support stop_after_client_disconnect

1. a global AllocStates to track status changes with timestamps. We
   need this to track the time at which the alloc became lost
   originally.

2. ShouldClientStop() and WaitClientStop() to actually do the math

* scheduler/reconcile_util: delayByStopAfterClientDisconnect

* scheduler/reconcile: use delayByStopAfterClientDisconnect

* scheduler/util: updateNonTerminalAllocsToLost comments

This was setup to only update allocs to lost if the DesiredStatus had
already been set by the scheduler. It seems like the intention was to
update the status from any non-terminal state, and not all lost allocs
have been marked stop or evict by now

* scheduler/testing: AssertEvalStatus just use require

* scheduler/generic_sched: don't create a blocked eval if delayed

* scheduler/generic_sched_test: several scheduling cases
2020-05-13 16:39:04 -04:00
Lang Martin ad2fb4b297 client/heartbeatstop: don't store client state, use timeout
In order to minimize this change while keeping a simple version of the
behavior, we set `lastOk` to the current time less the intial server
connection timeout. If the client starts and never contacts the
server, it will stop all configured tasks after the initial server
connection grace period, on the assumption that we've been out of
touch longer than any configured `stop_after_client_disconnect`.

The more complex state behavior might be justified later, but we
should learn about failure modes first.
2020-05-01 12:35:49 -04:00
Lang Martin 28bac139cb client/heartbeatstop: destroy allocs when disconnected from servers
- track lastHeartbeat, the client local time of the last successful
  heartbeat round trip
- track allocations with `stop_after_client_disconnect` configured
- trigger allocation destroy (which handles cleanup)
- restore heartbeat/killable allocs tracking when allocs are recovered from disk
- on client restart, stop those allocs after a grace period if the
  servers are still partioned
2020-05-01 12:35:49 -04:00