Processing an evaluation is nearly a pure function over the state
snapshot, but we randomly shuffle the nodes. This means that
developers can't take a given state snapshot and pass an evaluation
through it and be guaranteed the same plan results.
But the evaluation ID is already random, so if we use this as the seed
for shuffling the nodes we can greatly reduce the sources of
non-determinism. Unfortunately golang map iteration uses a global
source of randomness and not a goroutine-local one, but arguably
if the scheduler behavior is impacted by this, that's a bug in the
iteration.
The system scheduler should leave allocs on draining nodes as-is, but
stop node stop allocs on nodes that are no longer part of the job
datacenters.
Previously, the scheduler did not make the distinction and left system
job allocs intact if they are already running.
I've added a failing test first, which you can see in https://app.circleci.com/jobs/github/hashicorp/nomad/179661 .
Fixes https://github.com/hashicorp/nomad/issues/11373
Add a new hostname string parameter to the network block which
allows operators to specify the hostname of the network namespace.
Changing this causes a destructive update to the allocation and it
is omitted if empty from API responses. This parameter also supports
interpolation.
In order to have a hostname passed as a configuration param when
creating an allocation network, the CreateNetwork func of the
DriverNetworkManager interface needs to be updated. In order to
minimize the disruption of future changes, rather than add another
string func arg, the function now accepts a request struct along with
the allocID param. The struct has the hostname as a field.
The in-tree implementations of DriverNetworkManager.CreateNetwork
have been modified to account for the function signature change.
In updating for the change, the enhancement of adding hostnames to
network namespaces has also been added to the Docker driver, whilst
the default Linux manager does not current implement it.
This PR implements a new "System Batch" scheduler type. Jobs can
make use of this new scheduler by setting their type to 'sysbatch'.
Like the name implies, sysbatch can be thought of as a hybrid between
system and batch jobs - it is for running short lived jobs intended to
run on every compatible node in the cluster.
As with batch jobs, sysbatch jobs can also be periodic and/or parameterized
dispatch jobs. A sysbatch job is considered complete when it has been run
on all compatible nodes until reaching a terminal state (success or failed
on retries).
Feasibility and preemption are governed the same as with system jobs. In
this PR, the update stanza is not yet supported. The update stanza is sill
limited in functionality for the underlying system scheduler, and is
not useful yet for sysbatch jobs. Further work in #4740 will improve
support for the update stanza and deployments.
Closes#2527
Updates to the datacenter field should be destructive for any allocation that
is on a node no longer in the list of datacenters, but inplace for any
allocation on a node that is still in the list. Add a check for this change to
the system and generic schedulers after we've checked the task definition for
updates and obtained the node for each current allocation.
This PR adds the common OSS changes for adding support for Consul Namespaces,
which is going to be a Nomad Enterprise feature. There is no new functionality
provided by this changeset and hopefully no new bugs.
Start tracking a new MemoryMaxMB field that represents the maximum memory a task
may use in the client. This allows tasks to specify a memory reservation (to be
used by scheduler when placing the task) but use excess memory used on the
client if the client has any.
This commit adds the server tracking for the value, and ensures that allocations
AllocatedResource fields include the value.
node drain: use msgtype on txn so that events are emitted
wip: encoding extension to add Node.Drain field back to API responses
new approach for hiding Node.SecretID in the API, using `json` tag
documented this approach in the contributing guide
refactored the JSON handlers with extensions
modified event stream encoding to use the go-msgpack encoders with the extensions
Add a `PerAlloc` field to volume requests that directs the scheduler to test
feasibility for volumes with a source ID that includes the allocation index
suffix (ex. `[0]`), rather than the exact source ID.
Read the `PerAlloc` field when making the volume claim at the client to
determine if the allocation index suffix (ex. `[0]`) should be added to the
volume source ID.
This PR fixes a bug where tasks with Connect services could be
triggered to destructively update (i.e. placed in a new alloc)
when no update should be necessary.
Fixes#10077
* Persist shared allocated ports for inplace update
Ports were not copied over when performing inplace updates in the
generic scheduler
* changelog
* drop spew
AllocatedSharedResources were not being copied over to the new
allocation struct the scheduler makes during inplace updates. This
caused downstream issues after the plan was applied, namely the shared
ports were dropped causing issues with service
registration/deregistration.
test that shared ports are preserved
change log, also carry over shared network
copy networks
This PR fixes a long standing bug where submitting jobs with changes
to connect services would not trigger updates as expected. Previously,
service blocks were not considered as sources of destructive updates
since they could be synced with consul non-destructively. With Connect,
task group services that have changes to their connect block or to
the service port should be destructive, since the network plumbing of
the alloc is going to need updating.
Fixes#8596#7991
Non-destructive half in #7192
This change fixes a bug where lost/failed allocations are replaced by
allocations with the latest versions, even if the version hasn't been
promoted yet.
Now, when generating a plan for lost/failed allocations, the scheduler
first checks if the current deployment is in Canary stage, and if so, it
ensures that any lost/failed allocations is replaced one with the latest
promoted version instead.
* scheduler/reconcile: set FollowupEvalID on lost stop_after_client_disconnect
* scheduler/reconcile: thread follupEvalIDs through to results.stop
* scheduler/reconcile: comment typo
* nomad/_test: correct arguments for plan.AppendStoppedAlloc
* scheduler/reconcile: avoid nil, cleanup handleDelayed(Lost|Reschedules)
* 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
diffSystemAllocs -> diffSystemAllocsForNode, this function is only used
for diffing system allocations, but lacked awareness of eligible
nodes and the node ID that the allocation was going to be placed.
This change now ignores a change if its existing allocation is on an
ineligible node. For a new allocation, it also checks tainted and
ineligible nodes in the same function instead of nil-ing out the diff
after computation in diffSystemAllocs
If an alloc is being preempted and marked as evict, but the underlying
node is lost before the migration takes place, the allocation currently
stays as desired evict, status running forever, or until the node comes
back online.
This commit updates updateNonTerminalAllocsToLost to check for a
destired status of Evict as well as Stop when updating allocations on
tainted nodes.
switch to table test for lost node cases
Fixes documentation inaccuracy for spread stanza placement. Spreads can
only exist on the top level job struct or within a group.
comment about nil assumption
Adds checks for affinity and constraint changes when determining if we
should update inplace.
refactor to check all levels at once
check for spread changes when checking inplace update
Adds a new Prerun and Postrun hooks to manage set up of network namespaces
on linux. Work still needs to be done to make the code platform agnostic and
support Docker style network initalization.
IOPS have been modelled as a resource since Nomad 0.1 but has never
actually been detected and there is no plan in the short term to add
detection. This is because IOPS is a bit simplistic of a unit to define
the performance requirements from the underlying storage system. In its
current state it adds unnecessary confusion and can be removed without
impacting any users. This PR leaves IOPS defined at the jobspec parsing
level and in the api/ resources since these are the two public uses of
the field. These should be considered deprecated and only exist to allow
users to stop using them during the Nomad 0.9.x release. In the future,
there should be no expectation that the field will exist.
