We had two different, incompatible-with-each-other, and both
individually broken, partial implementations of resizing logic.
There's the original pre-etcd resize, and then the etcd resize,
and neither works, but there's conflicts between the ways they
don't work.
No attempt to fix this is likely to yield decent results, so
instead, we yank them both out entirely, so if we decide to
implement resizing (which we will) we won't be confused by
stray code pertaining to resizing that's not really hooked
up to anything.
We're leaving the resize messages in protobuf to avoid renumbering
protobuf messages. We rename some of our message types to UNUSED0,
etcetera, so that any code still using the old names won't
compile, to make sure we get rid of it, but we can't just drop
the numbers without breaking rolling restart.
The Resize_AddNode tests are removed not just because we don't
have resizing, but because they were completely broken anyway
and never worked at all. But there's no reason to fix them because
they exist to fix the functionality we didn't have and are now
removing the vestigial remains of.
We also drop the one usage of the AddNode function of Noder, because
it was used only by one test code fragment that was creatincg clusters,
and that can be done more correctly. There were no other call sites
at all.
We mark the monitorAntiEntropy function to be ignored by
code coverage because it's not actually being covered. There's
a separate ticket for removing that entirely.
MacOS's firewall complains about a previously unknown app trying to
listen for network connections whenever we run go test. That's because
we *are* listening for network connections on arbitrary interfaces, not
just on localhost as we probably intended. Fix that.
i used this script, a little clunky but it got the job done
```bash
for file in `find . -type f -print | grep '\.go'`; do
sed '1,/^\/\/ limitations under the License.$/d' $file > $file.tmp;
result=`cat $file.tmp`
if [[ result != "" ]]; then
gofmt $file.tmp &> /dev/null;
if [[ $? == 0 ]]; then
mv $file.tmp $file && gofmt -w $file;
else
rm $file.tmp;
fi
else
rm $file.tmp;
fi
done
```
These commits are hard to disentagle, and doing them separately means
re-modifying the same chunks of code several times before removing it,
and similar things.
Basically:
(1) Drop the bolt backend storage.
(2) Drop the blue-green wrapper that compares two backends.
(3) Drop unused or barely-used Tx API components from all the
remaining backends.
(4) Minor related cleanup to simplify things related to these.
The boltdb backend existed only to verify RBF. The blue-green wrapper
was mostly used to verify RBF, but in practice we had to do a lot
of working around that, and it introduced a lot of special cases.
Types removed:
IteratorFinder: Used only to implement the roaring iterator
on top of boltdb, and to complicate the way it worked in roaring.
Reverted the complications. Also unexport NewSliceContainers
which is used only for that outside of roaring's internals.
PortMapper from cluster_internal_test.go: Used only for a test
we removed early this year. Never used for anything else.
RawRoaringData: Totally unused.
TxStore: Totally unused.
Functions removed from Tx API, and sometimes corresponding
members were removed from structs:
* Dump: debugging code, I don't think I found any actually reachable
paths to it.
* Group: only used for debugging TxGroup stuff
* IncrementOpN: only used by fragment, fragment can increment its
own opN.
* Options: unused?
* Pointer: debugging only
* Readonly: used only to decide how to handle Tx in a TxGrp,
but we never add a non-readonly Tx to a TxGrp. Removed also all
the corresponding write-aware stuff.
* RoaringBitmapReader: Used exactly once, can just be a bm.WriteTo.
* Sn (and OpenSnList): Unused
* UnionInPlace: unused and conceptually-invalid; it didn't write
to storage and shouldn't have, and was just "create a bitmap
then call union-in-place", which we can do directly.
* UseRowCache: just checked storage.UseRowCache.
Other things removed:
The SetRequiredForAtomicWriteTx and ClearRequiredForAtomicWriteTx
functions go away, since nothing now seems to be using them? Same
for holder_internal_test's `testHasBit` and `testMustNotHaveBit`,
which were unused.
The DBPerShard "DeleteDBPath" and "HasData" functions and related
parts were mostly unused; took out the parts that were never
actually being reached.
Changed the API of one function to simplify special cases and
remove things:
* ImportRoaringBits had a special "data" argument which gave it
subtly different semantics for RBF and roaring (for roaring, it
could produce a roaring bitmap *with ops log*), didn't seem to
be adding much. Removed corresponding "readStorageFromArchive"
which is not otherwise used.
Also took out various debugging/dumping functions that were unused
and may have bitrotted.
Dropped a test from txfactory_internal_test, and the "pjobs"
code, because those two were the only things that needed Barrier
and thus idem, which lets us drop two more dependencies. We already
have errgroup for grouping things which want to terminate as
soon as one of them errors, approximately. To do better we'd have
to have context-threading, really.
Unbroke the WriteFragment test for non-roaring tests and made it
not roaring-only.
Attributes are unmaintained and unused.
They have become more of a liability than a benefit.
This change eliminates them from the codebase.
The only user-visible change (assuming that attrs are not used) is that the attrs field will no longer appear in row JSON.
A while back we started just polling the reported cluster state of one node
when starting a cluster for tests. This works fine if we're doing fresh
new etcd queries for every single operation -- but that's insanely
expensive, it turns out.
When we use the watcher, some nodes will report stale data for "a
while", where "a while" appears to be easily a couple dozen milliseconds.
This is probably irrelevant in most real-world cases, because the common
case (detecting a node going down) means that we have at least five
seconds after a node goes down before etcd notices the lease expiring,
and a few milliseconds more or less won't matter.
But we have tests that assume either that node 0 is always the
coordinator (wrong) or that waiting for node 0 to think the cluster
is up means that every node in the cluster thinks the cluster is up,
or at least that it means that the coordinator thinks the cluster is
up. We retried later operations but not the initial ones against
the coordinator.
In fact, we probably want to wait for the entire cluster to think
it's up before we start trying things on clusters.
We also replace the "CheckClusterState" function with the existing
AwaitState call, or a new AssertState which errors out since that's
the way we usually use AwaitState anyway.
In the AwaitPrimaryState function, which used to be
AwaitCoordinatorState in a different long-lost revision, we have
to delay until a primary node is available, or fail if one does
not become available, to avoid a panic. This probably shouldn't
happen anymore, because of the last change:
Also, rovide dummy topology.Node entries before metadata is read.
During initial startup, we want to be able to do things like determine
which node is the primary, even before we've read metadata from them.
To do this, we populate the node list with dummy entries that just have
the ID (the only part we need to sort our list), and a node state of
UNKNOWN.
This breaks the fancy logic for determining whether or not to update
the node data, because the initial status of UNKNOWN matches what we
get from SetMetadata giving us new data so we end up not realizing
that this was actually a meaningful change. But actually, that's
a pretty niche optimization; we usually only get state changes when
there's an actual change in state. The updates here are cheap
and only happen after a write (or on the first query) so it's not
worth making the logic a lot fancier to make it work, when we can
just do the simple thing and update any time the dirty flag is set.
We also standardize on a 50ms delay, because 1ms delays were
really expensive when each check was hitting etcd multiple times,
and 50ms is Usually Long Enough.
In nearly all cases, we can just switch ioutil.TempDir->testhook.TempDir
and similarly for TempFile. There's one case where we can't because we
need files to be removed before tests are over.
Also in the process give identifiable names to a lot of temporary files
and make sure they're being cleaned up, and don't use "/tmp/foo" as a
file name in a test that could be running in more than one test process
at once. :)
Long story short: Once we create a server and start it, we can't start
it again. We can't close it and restart it, and we can't just start
it without closing it.
Unfortunately, if the server's config needs to change, we have a Problem
here.
This ultimately means that the retry logic for GetListeners can't actually
retry successfully; if we fail on the first attempt, we necessarily fail
on any later attempts also, and if we try to fix that, we get panics.
But!
We don't actually NEED to retry. We just need to ensure that we can
open a :0 port, extract the actual port number, and use that in places
where the port number mattered, without having to rebind it.
The only actual place we needed to rebind things was opening gRPC
servers, so we introduce a gRPC Listener that can be used instead of
trying to bind to a specified port.
In a bunch of other cases where we had similar logic to try to allocate
and then use a port, we can switch to just using a provided listener.
For instance, net/http has `Serve(net.Listener, handler)`, not just
ListenAndServe(addr, handler).
This should eliminate the weird CI failures from eaddrinuse.
NOT fixed: server/cluster_test.go/TestClusterResize_AddNode isn't working
right now. The new node isn't actually being added to the existing cluster.
I attempted this but was outsmarted by it, and I think fixing the
rest of this is worth it as a separate thing.
Currently, if you issue a node removal from the node that is being
removed, then you will see a "node cannot be removed error". It's
not clear why you aren't able to remove the node. The error message
has been updated to clarify why.
port mapper gives out ports from 63000-65000 for the tests
fix another race
http test uses port.MustGetPort
rbf: remove :0 port request
ocd happy
test fix for grpc listener address already in use
test/disco allocates BindGRPC port from the port mapper
dump stack on each GetPort
verify each port is usable right away
server/config.go has Config.Validate() now
panic if gossip port is 0. validate server.Config
fix another gossip port 0
builds
quiet, don't dump stack on each port alloc
builds
happy linter
even gossip fallback should not be zero but rather use the port mapper
The testhook/ package provides an easy way to set up multiple
hooks to run before/after tests are run.
The audit hooks track open and closes of storage backends,
files, indexes, and holders, for example. A tempdir wrapper
creates temporary directories which are automatically cleaned up
when the test ends. Any kind of resource creation that
should be closed at test conclusion can be tracked. We
will complain at the end of the TestMain if resources are
leaking.
Leaks under go1.13:
We use a wrapper function which is a no-op for go 1.13, but actually
calls testing.TB.Cleanup in go1.14, so we can still build with 1.13 even though
tests will leak files all over the place there. Because of this,
don't run the testhook tests when using 1.13, as they'll always fail.
- the test/pilosa.go http client now times out after 10 seconds
to help diagnose hung server situations.
- Makefile targets added to get better progress reports.
- lmdb as a backend (lmdb.go)
(lmdb is the fastest known transactional storage backend)
- per Tx call statics report enabled with PILOSA_CALLSTAT=true (stattx.go)
- framework for per-shard db (dbshard.go)
- txfactory handles any pair under blue-green testing (txfactory.go)
- enable CGO in Dockerfiles for lmdb
Some cluster tests failed sporadically. In order to fix them, I
introduced some debugging-related functionality, which revealed
several new bugs that were actually existing bugs we just happened
not to hit in testing. This combines various fixes.
We start with "make the nodes used in testing have distinct names
based on the test case name", which lets us discover that we are
leaking clusters, which continue to sit around talking with each
other. That in turn causes significantly higher load on access to
ephemeral ports, which causes sporadic failures when we shut a
node down and try to restart it, but something else has gotten assigned
its ephemeral port number since then.
Part of the fix is to try to rebind on port 0 if an attempt to
bind to a specified port over 32k fails. This is a guess; the
actual ephemeral port range could be 16k+, 32k+, or 48k+, or just
about anything else really, but it seems reasonable in
practice.
There were bugs in the oft-repeated loops to await the cluster
achieving a given state, and it could hang forever if it didn't,
so we add a timeout and a standard function on the test.Cluster
type to handle that. Note that the timeout seems irrelevant; in
every case I've tried, a timeout of 0 is fine because the node
start doesn't complete until the cluster state has changed.
Add a method to test.Command to run a query, expecting a specific
result. Also clean up some of the formatting and generation of
queries, and allow parameterized (badly) queries. This lets us fix
a subtle bug, which is that test cases were depending on assumptions
about shardwidths. Also improve the diagnostic output from some of
these functions so test failures are more comprehensible.
But actually that dependency on shardwidths was ALSO revealing a
genuine underlying bug, which is that a node resize did not correctly
propagate the schema to a new node if there was no data present
on shards that node would own. We now also have a test case that
hits that (or would, if we hadn't fixed it).
Add comments explaining the server options parameters for MustNewCluster
and MustRunCluster.
Also, we implement the ReadFrom and WriteTo behaviors for
InMemTranslateStore, without which some of the cluster resize tests
fail. Props to the comment for specifically stating that they wouldn't
work if that happened, which probably saved me several hours of
debugging. The implementations may not be robust, but
InMemTranslateStore is intended to be used only in lightweight
and transient testing.
- Remove YAML magic
- Remove a lot of duplication
- Update linter
- Use parameterized jobs and matrix build
- Update Docker Hub CD to produce versioned and "latest" images
- Add custom shard width test to workflow
This commit adds `TranslationSources` to the cluster
`ResizeInstruction`. These are the sources of translation
partitions which the receiving node needs in order to support
partition distribution in the new, resized cluster.
This also fixes a bug where index options were not being
encode in the proto Index object. That meant that the schema
transferred via protobuf was not correct. The reason why
things normally worked is because index creation typically
happens on the CreateIndex message, which does include the
options.
TODO:
- [ ] implement the TranslateStore interface for `InMemTranslateStore`
and `mock.TranslateStore`
- [ ] surely need some more tests around the `ReadFrom` and `WriteTo`
