* fn: agent eviction revisited
Previously, the hot-container eviction logic used
number of waiters of cpu/mem resources to decide to
evict a container. An ejection ticker used to wake up
its associated container every 1 sec to reasses system
load based on waiter count. However, this does not work
for non-blocking agent since there are no waiters for
non-blocking mode.
Background on blocking versus non-blocking agent:
*) Blocking agent holds a request until the
the request is serviced or client times out. It assumes
the request can be eventually serviced when idle
containers eject themselves or busy containers finish
their work.
*) Non-blocking mode tries to limit this wait time.
However non-blocking agent has never been truly
non-blocking. This simply means that we only
make a request wait if we take some action in
the system. Non-blocking agents are configured with
a much higher hot poll frequency to make the system
more responsive as well as to handle cases where an
too-busy event is missed by the request. This is because
the communication between hot-launcher and waiting
requests are not 1-1 and lossy if another request
arrives for the same slot queue and receives a
too-busy response before the original request.
Introducing an evictor where each hot container can
register itself, if it is idle for more than 1 seconds.
Upon registry, these idle containers become eligible
for eviction.
In hot container launcher, in non-blocking mode,
before we attempt to emit a too-busy response, now
we attempt an evict. If this is successful, then
we wait some more. This could result in requests
waiting for more than they used to only if a
container was evicted. For blocking-mode, the
hot launcher uses hot-poll period to assess if
a request has waited for too long, then eviction
is triggered.
* fn: runner status and docker load images
Introducing a function run for pure runner Status
calls. Previously, Status gRPC calls returned active
inflight request counts with the purpose of a simple
health checker. However this is not sufficient since
it does not show if agent or docker is healthy. With
this change, if pure runner is configured with a status
image, that image is executed through docker. The
call uses zero memory/cpu/tmpsize settings to ensure
resource tracker does not block it.
However, operators might not always have a docker
repository accessible/available for status image. Or
operators might not want the status to go over the
network. To allow such cases, and in general possibly
caching docker images, added a new environment variable
FN_DOCKER_LOAD_FILE. If this is set, fn-agent during
startup will load these images that were previously
saved with 'docker save' into docker.
I've found this to be extremely useful. Not that I expect anyone to be able to
find this document on their own accord considering the breadth of
documentation that we have, this can still be useful for linking to from slack
at least (what docs are really for, right?)
also the triggers doc stuck out as confusing considering all the triggers
stuff going on, I was unable to comprehend how exactly it was helpful other
than making people aware that openstack exists and they could build an
extension into fn for it if they want to, but this seems true of most things?
so, removed it, if anyone objects maybe we could improve it a little?
* add user syslog writers to app
users may specify a syslog url[s] on apps now and all functions under that app
will spew their logs out to it. the docs have more information around details
there, please review those (swagger and operating/logging.md), tried to
implement to spec in some parts and improve others, open to feedback on
format though, lots of liberty there.
design decision wise, I am looking to the future and ignoring cold containers.
the overhead of the connections there will not be worth it, so this feature
only works for hot functions, since we're killing cold anyway (even if a user
can just straight up exit a hot container).
syslog connections will be opened against a container when it starts up, and
then the call id that is logged gets swapped out for each call that goes
through the container, this cuts down on the cost of opening/closing
connections significantly. there are buffers to accumulate logs until we get a
`\n` to actually write a syslog line, and a buffer to save some bytes when
we're writing the syslog formatting as well. underneath writers re-use the
line writer in certain scenarios (swapper). we could likely improve the ease
of setting this up, but opening the syslog conns against a container seems
worth it, and is a different path than the other func loggers that we create
when we make a call object. the Close() stuff is a little tricky, not sure how
to make it easier and have the ^ benefits, open to idears.
this does add another vector of 'limits' to consider for more strict service
operators. one being how many syslog urls can a user add to an app (infinite,
atm) and the other being on the order of number of containers per host we
could run out of connections in certain scenarios. there may be some utility
in having multiple syslog sinks to send to, it could help with debugging at
times to send to another destination or if a user is a client w/ someone and
both want the function logs, e.g. (have used this for that in the past,
specifically).
this also doesn't work behind a proxy, which is something i'm open to fixing,
but afaict will require a 3rd party dependency (we can pretty much steal what
docker does). this is mostly of utility for those of us that work behind a
proxy all the time, not really for end users.
there are some unit tests. integration tests for this don't sound very fun to
maintain. I did test against papertrail with each protocol and it works (and
even times out if you're behind a proxy!).
closes#337
* add trace to syslog dial
* Move out node-pool manager and replace it with RunnerPool extension
* adds extension points for runner pools in load-balanced mode
* adds error to return values in RunnerPool and Runner interfaces
* Implements runner pool contract with context-aware shutdown
* fixes issue with range
* fixes tests to use runner abstraction
* adds empty test file as a workaround for build requiring go source files in top-level package
* removes flappy timeout test
* update docs to reflect runner pool setup
* refactors system tests to use runner abstraction
* removes poolmanager
* moves runner interfaces from models to api/runnerpool package
* Adds a second runner to pool docs example
* explicitly check for request spillover to second runner in test
* moves runner pool package name for system tests
* renames runner pool pointer variable for consistency
* pass model json to runner
* automatically cast to http.ResponseWriter in load-balanced call case
* allow overriding of server RunnerPool via a programmatic ServerOption
* fixes return type of ResponseWriter in test
* move Placer interface to runnerpool package
* moves hash-based placer out of open source project
* removes siphash from Gopkg.lock
* add jaeger support, link hot container & req span
* adds jaeger support now with FN_JAEGER_URL, there's a simple tutorial in the
operating/metrics.md file now and it's pretty easy to get up and running.
* links a hot request span to a hot container span. when we change this to
sample at a lower ratio we'll need to finagle the hot container span to always
sample or something, otherwise we'll hide that info. at least, since we're
sampling at 100% for now if this is flipped on, can see freeze/unfreeze etc.
if they hit. this is useful for debugging. note that zipkin's exporter does
not follow the link at all, hence jaeger... and they're backed by the Cloud
Empire now (CNCF) so we'll probably use it anyway.
* vendor: add thrift for jaeger
* Initial stab at the protocol
* initial protocol sketch for node pool manager
* Added http header frame as a message
* Force the use of WithAgent variants when creating a server
* adds grpc models for node pool manager plus go deps
* Naming things is really hard
* Merge (and optionally purge) details received by the NPM
* WIP: starting to add the runner-side functionality of the new data plane
* WIP: Basic startup of grpc server for pure runner. Needs proper certs.
* Go fmt
* Initial agent for LB nodes.
* Agent implementation for LB nodes.
* Pass keys and certs to LB node agent.
* Remove accidentally left reference to env var.
* Add env variables for certificate files
* stub out the capacity and group membership server channels
* implement server-side runner manager service
* removes unused variable
* fixes build error
* splits up GetCall and GetLBGroupId
* Change LB node agent to use TLS connection.
* Encode call model as JSON to send to runner node.
* Use hybrid client in LB node agent.
This should provide access to get app and route information for the call
from an API node.
* More error handling on the pure runner side
* Tentative fix for GetCall problem: set deadlines correctly when reserving slot
* Connect loop for LB agent to runner nodes.
* Extract runner connection function in LB agent.
* drops committed capacity counts
* Bugfix - end state tracker only in submit
* Do logs properly
* adds first pass of tracking capacity metrics in agent
* maked memory capacity metric uint64
* maked memory capacity metric uint64
* removes use of old capacity field
* adds remove capacity call
* merges overwritten reconnect logic
* First pass of a NPM
Provide a service that talks to a (simulated) CP.
- Receive incoming capacity assertions from LBs for LBGs
- expire LB requests after a short period
- ask the CP to add runners to a LBG
- note runner set changes and readvertise
- scale down by marking runners as "draining"
- shut off draining runners after some cool-down period
* add capacity update on schedule
* Send periodic capcacity metrics
Sending capcacity metrics to node pool manager
* splits grpc and api interfaces for capacity manager
* failure to advertise capacity shouldn't panic
* Add some instructions for starting DP/CP parts.
* Create the poolmanager server with TLS
* Use logrus
* Get npm compiling with cert fixups.
* Fix: pure runner should not start async processing
* brings runner, nulb and npm together
* Add field to acknowledgment to record slot allocation latency; fix a bug too
* iterating on pool manager locking issue
* raises timeout of placement retry loop
* Fix up NPM
Improve logging
Ensure that channels etc. are actually initialised in the structure
creation!
* Update the docs - runners GRPC port is 9120
* Bugfix: return runner pool accurately.
* Double locking
* Note purges as LBs stop talking to us
* Get the purging of old LBs working.
* Tweak: on restart, load runner set before making scaling decisions.
* more agent synchronization improvements
* Deal with teh CP pulling out active hosts from under us.
* lock at lbgroup level
* Send request and receive response from runner.
* Add capacity check right before slot reservation
* Pass the full Call into the receive loop.
* Wait for the data from the runner before finishing
* force runner list refresh every time
* Don't init db and mq for pure runners
* adds shutdown of npm
* fixes broken log line
* Extract an interface for the Predictor used by the NPM
* purge drained connections from npm
* Refactor of the LB agent into the agent package
* removes capacitytest wip
* Fix undefined err issue
* updating README for poolmanager set up
* ues retrying dial for lb to npm connections
* Rename lb_calls to lb_agent now that all functionality is there
* Use the right deadline and errors in LBAgent
* Make stream error flag per-call rather than global otherwise the whole runner is damaged by one call dropping
* abstracting gRPCNodePool
* Make stream error flag per-call rather than global otherwise the whole runner is damaged by one call dropping
* Add some init checks for LB and pure runner nodes
* adding some useful debug
* Fix default db and mq for lb node
* removes unreachable code, fixes typo
* Use datastore as logstore in API nodes.
This fixes a bug caused by trying to insert logs into a nil logstore. It
was nil because it wasn't being set for API nodes.
* creates placement abstraction and moves capacity APIs to NodePool
* removed TODO, added logging
* Dial reconnections for LB <-> runners
LB grpc connections to runners are established using a backoff stategy
in event of reconnections, this allows to let the LB up even in case one
of the runners go away and reconnect to it as soon as it is back.
* Add a status call to the Runner protocol
Stub at the moment. To be used for things like draindown, health checks.
* Remove comment.
* makes assign/release capacity lockless
* Fix hanging issue in lb agent when connections drop
* Add the CH hash from fnlb
Select this with FN_PLACER=ch when launching the LB.
* small improvement for locking on reloadLBGmembership
* Stabilise the list of Runenrs returned by NodePool
The NodePoolManager makes some attempt to keep the list of runner nodes advertised as
stable as possible. Let's preserve this effort in the client side. The main point of this
is to attempt to keep the same runner at the same inxed in the []Runner returned by
NodePool.Runners(lbgid); the ch algorithm likes it when this is the case.
* Factor out a generator function for the Runners so that mocks can be injected
* temporarily allow lbgroup to be specified in HTTP header, while we sort out changes to the model
* fixes bug with nil runners
* Initial work for mocking things in tests
* fix for anonymouse go routine error
* fixing lb_test to compile
* Refactor: internal objects for gRPCNodePool are now injectable, with defaults for the real world case
* Make GRPC port configurable, fix weird handling of web port too
* unit test reload Members
* check on runner creation failure
* adding nullRunner in case of failure during runner creation
* Refactored capacity advertisements/aggregations. Made grpc advertisement post asynchronous and non-blocking.
* make capacityEntry private
* Change the runner gRPC bind address.
This uses the existing `whoAmI` function, so that the gRPC server works
when the runner is running on a different host.
* Add support for multiple fixed runners to pool mgr
* Added harness for dataplane system tests, minor refactors
* Add Dockerfiles for components, along with docs.
* Doc fix: second runner needs a different name.
* Let us have three runners in system tests, why not
* The first system test running a function in API/LB/PureRunner mode
* Add unit test for Advertiser logic
* Fix issue with Pure Runner not sending the last data frame
* use config in models.Call as a temporary mechanism to override lb group ID
* make gofmt happy
* Updates documentation for how to configure lb groups for an app/route
* small refactor unit test
* Factor NodePool into its own package
* Lots of fixes to Pure Runner - concurrency woes with errors and cancellations
* New dataplane with static runnerpool (#813)
Added static node pool as default implementation
* moved nullRunner to grpc package
* remove duplication in README
* fix go vet issues
* Fix server initialisation in api tests
* Tiny logging changes in pool manager.
Using `WithError` instead of `Errorf` when appropriate.
* Change some log levels in the pure runner
* fixing readme
* moves multitenant compute documentation
* adds introduction to multitenant readme
* Proper triggering of system tests in makefile
* Fix insructions about starting up the components
* Change db file for system tests to avoid contention in parallel tests
* fixes revisions from merge
* Fix merge issue with handling of reserved slot
* renaming nulb to lb in the doc and images folder
* better TryExec sleep logic clean shutdown
In this change we implement a better way to deal with the sleep inside
the for loop during the attempt for placing a call.
Plus we added a clean way to shutdown the connections with external
component when we shut down the server.
* System_test mysql port
set mysql port for system test to a different value to the one set for
the api tests to avoid conflicts as they can run in parallel.
* change the container name for system-test
* removes flaky test TestRouteRunnerExecution pending resolution by issue #796
* amend remove_containers to remove new added containers
* Rework capacity reservation logic at a higher level for now
* LB agent implements Submit rather than delegating.
* Fix go vet linting errors
* Changed a couple of error levels
* Fix formatting
* removes commmented out test
* adds snappy to vendor directory
* updates Gopkg and vendor directories, removing snappy and addhing siphash
* wait for db containers to come up before starting the tests
* make system tests start API node on 8085 to avoid port conflict with api_tests
* avoid port conflicts with api_test.sh which are run in parallel
* fixes postgres port conflict and issue with removal of old containers
* Remove spurious println
*) Limit response http body or json response size to FN_MAX_RESPONSE_SIZE (default unlimited)
*) If limits are exceeded 502 is returned with 'body too large' in the error message
* fn: hot container timer improvements
With this change, now we are allocating the timers
when the container starts and managing them via
stop/clear as needed, which should not only be more
efficient, but also easier to follow.
For example, previously, if eject time out was
set to 10 secs, this could have delayed idle timeout
up to 10 secs as well. It is also not necessary to do
any math for elapsed time.
Now consumers avoid any requeuing when startDequeuer() is cancelled.
This was triggering additional dequeue/requeue causing
containers to wake up spuriously. Also in startDequeuer(),
we no longer remove the item from the actual queue and
leave this to acquire/eject, which side steps issues related
with item landing in the channel, not consumed, etc.
* add FN_LOG_DEST for logs, fixup init
* FN_LOG_DEST can point to a remote logging place (papertrail, whatever)
* FN_LOG_PREFIX can add a prefix onto each log line sent to FN_LOG_DEST
default remains stderr with no prefix. users need this to send to various
logging backends, though it could be done operationally, this is somewhat
simpler.
we were doing some configuration stuff inside of init() for some of the global
things. even though they're global, it's nice to keep them all in the normal
server init path.
we have had strange issues with the tracing setup, I tested the last repro of
this repeatedly and didn't have any luck reproducing it, though maybe it comes
back.
* add docs
* Docker compose file for simpler dev env
* Updating readme, adding UI to compose
* Define dependencies between services
* Prometheus. Grafana
* Link Prometheus to Grafana service
* Addressing review comments
* Linking compose doc to common table of content
* add minio-go dep, update deps
* add minio s3 client
minio has an s3 compatible api and is an open source project and, notably, is
not amazon, so it seems best to use their client (fwiw the aws-sdk-go is a
giant hair ball of things we don't need, too). it was pretty easy and seems
to work, so rolling with it. also, minio is a totally feasible option for fn
installs in prod / for demos / for local.
* adds 's3' package for s3 compatible log storage api, for use with storing
logs from calls and retrieving them.
* removes DELETE /v1/apps/:app/calls/:call/log endpoint
* removes internal log deletion api
* changes the GetLog API to use an io.Reader, which is a backwards step atm
due to the json api for logs, I have another branch lined up to make a plain
text log API and this will be much more efficient (also want to gzip)
* hooked up minio to the test suite and fixed up the test suite
* add how to run minio docs and point fn at it docs
some notes: notably we aren't cleaning up these logs. there is a ticket
already to make a Mr. Clean who wakes up periodically and nukes old stuff, so
am punting any api design around some kind of TTL deletion of logs. there are
a lot of options really for Mr. Clean, we can notably defer to him when apps
are deleted, too, so that app deletion is fast and then Mr. Clean will just
clean them up later (seems like a good option).
have not tested against BMC object store, which has an s3 compatible API. but
in theory it 'just works' (the reason for doing this). in any event, that's
part of the service land to figure out.
closes#481closes#473
* add log not found error to minio land
* split fn-ui to its own service
* add fn namespace
* update path
* add namespace flag for kubectl
* simplify grabbing minikube IP and port
* typo: FUNCTIONS -> API_URL
* adds migrations
closes#57
migrations only run if the database is not brand new. brand new
databases will contain all the right fields when CREATE TABLE is called,
this is for readability mostly more than efficiency (do not want to have
to go through all of the database migrations to ascertain what columns a table
has). upon startup of a new database, the migrations will be analyzed and the
highest version set, so that future migrations will be run. this should also
avoid running through all the migrations, which could bork db's easily enough
(if the user just exits from impatience, say).
otherwise, all migrations that a db has not yet seen will be run against it
upon startup, this should be seamless to the user whether they had a db that
had 0 migrations run on it before or N. this means users will not have to
explicitly run any migrations on their dbs nor see any errors when we upgrade
the db (so long as things go well). if migrations do not go so well, users
will have to manually repair dbs (this is the intention of the `migrate`
library and it seems sane), this should be rare, and I'm unsure myself how
best to resolve not having gone through this myself, I would assume it will
require running down migrations and then manually updating the migration
field; in any case, docs once one of us has to go through this.
migrations are written to files and checked into version control, and then use
go-bindata to generate those files into go code and compiled in to be consumed
by the migrate library (so that we don't have to put migration files on any
servers) -- this is also in vcs. this seems to work ok. I don't like having to
use the separate go-bindata tool but it wasn't really hard to install and then
go generate takes care of the args. adding migrations should be relatively
rare anyway, but tried to make it pretty painless.
1 migration to add created_at to the route is done here as an example of how
to do migrations, as well as testing these things ;) -- `created_at` will be
`0001-01-01T00:00:00.000Z` for any existing routes after a user runs this
version. could spend the extra time adding 'today's date to any outstanding
records, but that's not really accurate, the main thing is nobody will have to
nuke their db with the migrations in place & we don't have any prod clusters
really to worry about. all future routes will correctly have `created_at` set,
and plan to add other timestamps but wanted to keep this patch as small as
possible so only did routes.created_at.
there are tests that a spankin new db will work as expected as well as a db
after running all down & up migrations works. the latter tests only run on mysql
and postgres, since sqlite3 does not like ALTER TABLE DROP COLUMN; up
migrations will need to be tested manually for sqlite3 only, but in theory if
they are simple and work on postgres and mysql, there is a good likelihood of
success; the new migration from this patch works on sqlite3 fine.
for now, we need to use `github.com/rdallman/migrate` to move forward, as
getting integrated into upstream is proving difficult due to
`github.com/go-sql-driver/mysql` being broken on master (yay dependencies).
Fortunately for us, we vendor a version of the `mysql` bindings that actually
works, thus, we are capable of using the `mattes/migrate` library with success
due to that. this also will require go1.9 to use the new `database/sql.Conn`
type, CI has been updated accordingly.
some doc fixes too from testing.. and of course updated all deps.
anyway, whew. this should let us add fields to the db without busting
everybody's dbs. open to feedback on better ways, but this was overall pretty
simple despite futzing with mysql.
* add migrate pkg to deps, update deps
use rdallman/migrate until we resolve in mattes land
* add README in migrations package
* add ref to mattes lib
