In the spirit of #25909, this PR removes testify dependencies from the scheduler
package, along with reflect.DeepEqual removal. This is again a combination of
semgrep and hx editing magic.
---------
Co-authored-by: Tim Gross <tgross@hashicorp.com>
* Set MaxAllocations in client config
Add NodeAllocationTracker struct to Node struct
Evaluate MaxAllocations in AllocsFit function
Set up cli config parsing
Integrate maxAllocs into AllocatedResources view
Co-authored-by: Tim Gross <tgross@hashicorp.com>
---------
Co-authored-by: Tim Gross <tgross@hashicorp.com>
If there are no affinities on a job, we don't want to count an affinity score of
zero in the number of scores we divide the normalized score by. This is how we
handle other scoring components like node reschedule penalties on nodes that
weren't running the previous allocation.
But we also exclude counting the affinity in the case where we have affinity but
the value is zero. In pathological cases, this can result in a node with a low
affinity being picked over a node with no affinity, because the denominator is 1
larger. Include zero-value affinities in the count of scores if the job has
affinities but the value just happens to be zero.
Fixes: https://github.com/hashicorp/nomad/issues/25621
(CE backport of ENT 59433d56c7215c0b8bf33764f41b57d9bd30160f (without ent files))
* scheduler: enhance numa aware scheduling with support for devices
* cr: add comments
On supported platforms, the secrets directory is a 1MiB tmpfs. But some tasks
need larger space for downloading large secrets. This is especially the case for
tasks using `templates`, which need extra room to write a temporary file to the
secrets directory that gets renamed to the old file atomically.
This changeset allows increasing the size of the tmpfs in the `resources`
block. Because this is a memory resource, we need to include it in the memory we
allocate for scheduling purposes. The task is already prevented from using more
memory in the tmpfs than the `resources.memory` field allows, but can bypass
that limit by writing to the tmpfs via `template` or `artifact` blocks.
Therefore, we need to account for the size of the tmpfs in the allocation
resources. Simply adding it to the memory needed when we create the allocation
allows it to be accounted for in all downstream consumers, and then we'll
subtract that amount from the memory resources just before configuring the task
driver.
For backwards compatibility, the default value of 1MiB is "free" and ignored by
the scheduler. Otherwise we'd be increasing the allocated resources for every
existing alloc, which could cause problems across upgrades. If a user explicitly
sets `resources.secrets = 1` it will no longer be free.
Fixes: https://github.com/hashicorp/nomad/issues/2481
Ref: https://hashicorp.atlassian.net/browse/NET-10070
The NUMA topology struct field `NodeIDs` is a `idset.Set`, which has no public
members. As a result, this field is never serialized via msgpack and persisted
in state. When `numa.affinity = "prefer"`, the scheduler dereferences this nil
field and panics the scheduler worker.
Ideally we would fix this by adding a msgpack serialization extension, but
because the field already exists and is just always empty, this breaks RPC wire
compatibility across upgrades. Instead, create a new field that's populated at
the same time we populate the more useful `idset.Set`, and repopulate the set on
demand.
Fixes: https://hashicorp.atlassian.net/browse/NET-9924
* core: plumbing to support numa aware scheduling
* core: apply node resources compatibility upon fsm rstore
Handle the case where an upgraded server dequeus an evaluation before
a client triggers a new fingerprint - which would be needed to cause
the compatibility fix to run. By running the compat fix on restore the
server will immediately have the compatible pseudo topology to use.
* lint: learn how to spell pseudo
Fixes#13505
This fixes#13505 by treating reserved_ports like we treat a lot of jobspec settings: merging settings from more global stanzas (client.reserved.reserved_ports) "down" into more specific stanzas (client.host_networks[].reserved_ports).
As discussed in #13505 there are other options, and since it's totally broken right now we have some flexibility:
Treat overlapping reserved_ports on addresses as invalid and refuse to start agents. However, I'm not sure there's a cohesive model we want to publish right now since so much 0.9-0.12 compat code still exists! We would have to explain to folks that if their -network-interface and host_network addresses overlapped, they could only specify reserved_ports in one place or the other?! It gets ugly.
Use the global client.reserved.reserved_ports value as the default and treat host_network[].reserverd_ports as overrides. My first suggestion in the issue, but @groggemans made me realize the addresses on the agent's interface (as configured by -network-interface) may overlap with host_networks, so you'd need to remove the global reserved_ports from addresses shared with a shared network?! This seemed really confusing and subtle for users to me.
So I think "merging down" creates the most expressive yet understandable approach. I've played around with it a bit, and it doesn't seem too surprising. The only frustrating part is how difficult it is to observe the available addresses and ports on a node! However that's a job for another PR.
Cluster operators want to have better control over memory
oversubscription and may want to enable/disable it based on their
experience.
This PR adds a scheduler configuration field to control memory
oversubscription. It's additional field that can be set in the [API via Scheduler Config](https://www.nomadproject.io/api-docs/operator/scheduler), or [the agent server config](https://www.nomadproject.io/docs/configuration/server#configuring-scheduler-config).
I opted to have the memory oversubscription be an opt-in, but happy to change it. To enable it, operators should call the API with:
```json
{
"MemoryOversubscriptionEnabled": true
}
```
If memory oversubscription is disabled, submitting jobs specifying `memory_max` will get a "Memory oversubscription is not
enabled" warnings, but the jobs will be accepted without them accessing
the additional memory.
The warning message is like:
```
$ nomad job run /tmp/j
Job Warnings:
1 warning(s):
* Memory oversubscription is not enabled; Task cache.redis memory_max value will be ignored
==> Monitoring evaluation "7c444157"
Evaluation triggered by job "example"
==> Monitoring evaluation "7c444157"
Evaluation within deployment: "9d826f13"
Allocation "aa5c3cad" created: node "9272088e", group "cache"
Evaluation status changed: "pending" -> "complete"
==> Evaluation "7c444157" finished with status "complete"
# then you can examine the Alloc AllocatedResources to validate whether the task is allowed to exceed memory:
$ nomad alloc status -json aa5c3cad | jq '.AllocatedResources.Tasks["redis"].Memory'
{
"MemoryMB": 256,
"MemoryMaxMB": 0
}
```
* use msgtype in upsert node
adds message type to signature for upsert node, update tests, remove placeholder method
* UpsertAllocs msg type test setup
* use upsertallocs with msg type in signature
update test usage of delete node
delete placeholder msgtype method
* add msgtype to upsert evals signature, update test call sites with test setup msg type
handle snapshot upsert eval outside of FSM and ignore eval event
remove placeholder upsertevalsmsgtype
handle job plan rpc and prevent event creation for plan
msgtype cleanup upsertnodeevents
updatenodedrain msgtype
msg type 0 is a node registration event, so set the default to the ignore type
* fix named import
* fix signature ordering on upsertnode to match
The BinPackIter accounted for node reservations twice when scoring nodes
which could bias scores toward nodes with reservations.
Pseudo-code for previous algorithm:
```
proposed = reservedResources + sum(allocsResources)
available = nodeResources - reservedResources
score = 1 - (proposed / available)
```
The node's reserved resources are added to the total resources used by
allocations, and then the node's reserved resources are later
substracted from the node's overall resources.
The new algorithm is:
```
proposed = sum(allocResources)
available = nodeResources - reservedResources
score = 1 - (proposed / available)
```
The node's reserved resources are no longer added to the total resources
used by allocations.
My guess as to how this bug happened is that the resource utilization
variable (`util`) is calculated and returned by the `AllocsFit` function
which needs to take reserved resources into account as a basic
feasibility check.
To avoid re-calculating alloc resource usage (because there may be a
large number of allocs), we reused `util` in the `ScoreFit` function.
`ScoreFit` properly accounts for reserved resources by subtracting them
from the node's overall resources. However since `util` _also_ took
reserved resources into account the score would be incorrect.
Prior to the fix the added test output:
```
Node: reserved Score: 1.0000
Node: reserved2 Score: 1.0000
Node: no-reserved Score: 0.9741
```
The scores being 1.0 for *both* nodes with reserved resources is a good
hint something is wrong as they should receive different scores. Upon
further inspection the double accounting of reserved resources caused
their scores to be >1.0 and clamped.
After the fix the added test outputs:
```
Node: no-reserved Score: 0.9741
Node: reserved Score: 0.9480
Node: reserved2 Score: 0.8717
```
Also includes unit tests for binpacker and preemption.
The tests verify that network resources specified at the
task group level are properly accounted for
Also changes the logic for score when there is more than one task
requesting a device. Since inter task affinities are already normalized,
we take the average of the scores across tasks.