* expose Transaction on TranslateStore for DAX Snapshotting
* try to fix ramdisk nonsense
apparently, we were running in either a shell env or docker env
randomly, so this could sometimes pass and sometimes fail since the
shell env had the ramdisk set up and docker didn't.
Now we force to run in docker always and set up ramdisk explicitly.
* ramdisk mount should be defined on gitlab runner config now
* debug ramdisk issue?
* fix tests... and a buncha other stuff
Took retry out of CI config because I think it's doing more harm than
good at this point.
The executor test I modified failed when I changed DefaultPartitionN
to 8, but just because stuff was out of order so I made it more
robust.
I edited some data gen stuff to make shorter lines because it was
making grep results unusable.
the actual fix is in translate_boltdb_test.go
* clean up, fix code review feedback
The internal/ingest and internal/schema endpoints were developed with
intent that they'd be the primary interface new users would work with,
because they were Easy To Use, and did not require any kind of setup,
the counterpoint being that ingest done this way had performance issues
because it ended up with huge amounts of JSON parsing to reformat
things into our native format. But this was understood to be the price
of providing a new-user-friendly JSON ingest experience.
A year later, we have no evidence that it's ever been used. We never
even moved it out of the `/internal` path. It's a lot of very complex
fiddly code and we don't seem to be using it, and at this point, our
anticipation is that if we really need something, we'll use CSV, which
we already have working, or something in the new SQL code. Either way,
we don't seem to be using this.
The root problem this is attempting to address is sporadic
weird cases in which etcd mistakenly thinks it's down even when
it's up. I am not confident that this is addressed, but there's
a reasonable chance that it is, and I can't trigger it at the
moment, but it was always sporadic, so that doesn't prove much.
There's a lot going on here, and it comes into roughly three
categories.
First: Dropping unused/unneeded code. There's a lot of leftover
bits from the initial development and refactoring of this.
Second: Unifying and shuffling some of the design. We had
multiple interfaces which are functionally impossible to
usefully implement separately, so they're combined together,
and in some cases, moved.
Third: Streamlining logic and simplifying design choices.
This is combined into one commit because the changes are
thoroughly entertwined with each other and you can't usefully
break most of them out.
Also, a bunch of test coverage for most of these changes.
Big changes:
We merge the topology and disco packages. The topology and disco
packages being separate creates a complicated tangle of problems
and dependencies. The fundamental problem, approximately, is that
topology.Node has to track disco.NodeState.
There's three core interfaces interacting here:
topology.Noder (maintains list of nodes)
disco.Stator (maintains the state of a node)
disco.Metadator (stores, possibly retrieves, node metadata)
But the node state mantained by the Noder *is* the set of node
metadata, plus state updates produced by Stators. The only actual
non-trivial and usable implementation of these interfaces is a single
thing which implements all three, and in which the implementations
share a single backend data source which they are all modifying.
But you can't move Noder into disco, because Noder has to refer
to topology.Node, but topology.Node refers to disco.
Solution: First, merge these two packages. Second, merge these
three interfaces, to provide a single interface which is more
clear about the fact that (metadator.)SetMetadata() and
(stator.)Started() are both changing the output we'll get from
(noder.)Nodes().
We rework the node state tracking.
We have this nodeStates map which is almost unused. Really, we
don't need it at all. Every node's state is either its last heartbeat
state or "Unknown", so we simplify this a bit. Also, we ensure that
the populateNodeStates function itself is yielding the sorted nodes
list, so we don't have to be as worried about possible later lookups
of sortedNodes happening outside a lock. We also add diagnostics
for deleting nodes from the metadata list (this should never happen),
and try to track heartbeat state more closely.
This is *probably* what fixes the underlying reported problem,
if anything did.
Still an open issue: Make heartbeat state changes aware of when
they're talking about *this* node and possibly not try to
mark it down? Except this may have a flaw: That would result in
each node disagreeing with other nodes in etcd about the state
of that node in the failure cases, and undermine the point of
using etcd to keep these states consistent.
We reduce the number of contexts and cancelfuncs in the etcd wrapper.
We create a shared context for the non-etcd.embed children of our
etcd wrapper, the heartbeat/keepalive and the node watcher, so we
can cancel that one context and cancel all of those at once, so
we don't need to separately track a function to call to cancel
the watch, AND be closing another channel. Also, our shutdown
now propagates automatically to the various etcd API calls we've
made for things like the node watcher and keepalive calls.
We still need to watch that channel in watchNodesOnce, though,
because apparently the watch doesn't yield an error even if the
context calling it is canceled. Whee.
This should reduce the risk of ending up in an inconsistent state,
and also the Close() function is probably idempotent now.
Smaller changes:
* Remove config-generators that existed to generate etcd
configs but were used only for tests that no longer exist
or make sense.
* Move the logic to generate etcd configs into the etcd
package, instead of the "testing" subpackage. This allows
us to write a self-contained config generator for
clusters where the nodes know about each other, but do
this just with etcd, not with full featurebase servers.
* Move the thing generating `fake:%d` socket names into
the etcd package, which is the only place we use it.
Also simplify it slightly.
* Don't panic on invalid URLs, report errors from them.
* At least try to use etcd's config.Validate functionality.
It's underdocumented, so we're not sure what it will report,
but at least if it does we'll get reports from it and
know what they are?
* Try to handle CompactRevision errors from watches more
correctly -- after a CompactRevision, any future attempt
to watch from a lower revision will necessarily fail, so
we adjust our target revision up. We don't have good
testing for this.
* Drop the Metadata() method (that used to be in Metadator)
because nothing ever used it and it didn't make much sense
to try.
* Convert SetMetadata from taking an arbitrary json blob
to taking the only data that would ever be valid since
we always use it to extract node information anyway.
* Drop several unused functions, unexport things only used
internally.
* Replace Started() with SetState("STARTED"), allowing us
to write tests that mess with states. We weren't really thinking
carefully about state transitions sometimes and now it's much
easier to do that thinking.
* Stop leaving stray localhost:2380 and localhost:2379 in
our embed config. We still sometimes see peer requests from
those and I honestly don't know why, but at least it should
be rarer.
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
```
Performance of tests on MacOS has been atrocious for a while, and
a lot of that is fsync, so we're trying to make that optional.
To test all of this, I modified RBF to panic if anything tried to
open an RBF database without disabling fsync, and ran the tests that
way, and tracked down the various places this could still happen.
There's a lot of places in our tree where we were creating
test holders which were not getting created with fsync disabled, which
results in a surprisingly large number of points at which we end
up calling fsync in tests, which makes tests much slower than they
need to be. There's also a bunch of places where the flags don't get
propagated correctly; for instance, storage.fsync didn't propagate
to the RBFConfig.
We add an "fsync enabled" flag to OpenTranslateStoreFunc, so we can
tell translation stores that we don't need syncing, so the server's
config can be passed on appropriately.
More of the test code that sets things up is correctly configuring
that flag by default.
We also change the barely-used bolt storage backend to support this as
well.
With this done, the only calls to fsync left in a run of `go test -short`
in the top-level directory are from the zap logger in etcd, and consumed
around 0.03 seconds. The overall impact is that `go test -short`
went from "takes enough more than 10 minutes that i don't know how long
it takes" to about 2.5 minutes.
We add endpoints and protobuf encode/decode to allow for sending
sharded requests over the wire in protobuf, so we can take our
sharded data and send it to other nodes if needed.
This is a squash of >15 other commits, so a bit of history
is relevant:
The Request type had FieldTypes in it because the field type
information was needed for sharding because sorting requires
that information. We change this around to make the external
sharding operation require the field types, and curry that
through the codec -- the codec is needed to tell the request
how it shards. (This is because the correct sorting order
varies by field type.) Requests (and ShardedRequests) no
longer have that table in them.
And then we hit a nasty bug in production and RCA showed
that our testing wasn't good enough and we need to be more
careful, and I discovered that test coverage in this package
was around 70%.
So, the other big thing here is coverage testing; in order to
make coverage testing viable and programmatically testable,
we have added the ability to render requests *back* to
JSON. This is not a great idea, but it does allow us to do
a lot of sanity-checking and verify that the encodings we're
using are consistent and correct.
This, plus some specific tests of decoding specific flawed
inputs, has caught a number of issues. Which are now fixed!
A lot of internal API surface got slightly changed, in ways
that make it simpler to work with. For instance, the
(*FieldOperation).TranslateUnsigned function doesn't really
need to exist; we can just have a non-method translate
function for unsigned and for signed, and use them based on
field type.
The stable translation hack used for testing had a bug that
could allow it to end up producing incorrect results if you
asked it to translate an ID first rather than exclusively
asking it to translate strings first, this has been
corrected. (This is a bug fix in code that was added
partway through creating this, but is tricky enough to
mention its own comment.)
Test coverage is now just over 90%, and a lot of what's left
is error-check returns that may well be actually unreachable
unless, say, the documentation for encoding/json is full of
lies. Which it probably is.
This migrates existing code from the old TranslateKey(s) endpoints to the newer CreateKeys and FindKeys endpoints.
The CreateKeys and FindKeys endpoints were created previously as the TranslateKeys endpoint had no way to behave sanely when the looked-up key did not exist (the parallel-arrays representation did not have a good way to represent a missing key).
This change also removes the old TranslateKey(s) functions from the translation stores.
It leaves a wrapper emulating the TranslateKey(s) endpoints so that old idk still works for now.
This works around an issue where unreplicated keys will not be matched everywhere.
This also avoids the cost of creating millions of bolt read transactions and allocating strings.
There's no need to have two different translation readers, a single
reader can handle both partitions and fields at the same time, so we
can combine them. This may not actually change things much but was
a useful step in diagnosing a different problem with translate readers,
and I think it is a minor improvement so I'm preserving the patch
just in case.
- the -fix flag repairs replication errors by copying from the primary.
- the -fixkeys flag repairs any string key translation issues.
- make pilosa-fsck installs pilosa-fsck and builds release-pilosa-fsck.COMMIT.GOOS.tar.gz release tarbar
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.
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`
break in a select in a for terminates the current case of the
select, but does not terminate the for loop. The worker queue
implementations for opening indexes/fields/views all suffered
from the same issue here.
Also fix a `<= 0` on a uint value.
All hail staticcheck.
This commit fixes an issue where translation `LogEntry` must be
read in its entirety, however, large entries can exceed the buffer
size. This has been changed so that partial entries reads are allowed.
The `LogEntry.ReadFrom()` may still generate large byte slices
during reads of large individual fields or keys.
Depending on where in the replicate() loop you are when a
store is closed or reassigned, it's possible for it to deadlock.
The deadlock would be that replicate has just successfully read an
entry from your PrimaryTranslateStore.Reader, when a new
PrimaryTranslateStore event happens. Then handlePrimaryTranslateStore
grabs the mutex, signals that the replication handler should
close, and waits for the replication handler to close. Meanwhile,
the replicate() loop tries to grab the mutex... and deadlocks.
Solution: Make the replicate() loop part that needs the mutex
a goroutine that signals on a channel, so we can put it in a select
along with checking for the replicationClosing signal (or the
context terminating). If one of those happens, replicate()
terminates, allowing monitorReplication() to return, which
causes the anonymous function which called it to call
repWG.Done(), allowing handlePrimaryTranslateStore to continue
and eventually release the mutex. At some later point, appendEntry
succeeds or fails, dumps its result status in a buffered
channel, and exits, and the buffered channel is garbage collected.
This is way simpler than it sounds, but it took me a while
to figure out how simple it was.
In the case where a translate log entry contained
many key/id pairs, it was possible for the read
buffer (which was allocated at 65536 bytes) to
fail to handle it. This happened when the serialized
LogEntry was larger than 65536 bytes.
This PR adds logic which returns a custom error called
ErrTranslateReadTargetUndersized notifying the reader
to reallocate a larger read buffer and try the read
again.
TODO:
- [ ] Add a max buffer size check to prevent this from doubling the
buffer size with no limit.
- [ ] Add tests.
I'd like to add stat tracking to Roaring, which means it
has to be able to import the stats package, which means
stats has to be a package rather than part of the pilosa
package. If stats stops being in pilosa, it still needs
a way to import logger, so logger also has to leave the
pilosa package. Then everything using them needs to import
them and use package selectors on their names.
This doesn't actually add the stats support to roaring,
it just makes it so there's a way to import the stats
code from something in the roaring package.
