This commit adds a buffer for stats to be updated without
requiring a mutex lock/unlock on every point. The tradeoff
is that stats are not exactly precise. This works for our
use case because stats are only periodically checked.
If an OR was used, merging filters between different expressions would
not work correctly. If one of the sides had a set of series ids with a
condition and the other side had no series ids associated with the
expression, all of the series from the side with a condition would have
the condition ignored. Instead of defaulting a non-existant series
filter to true, it should just be false and the evaluation of the one
side that does exist should take care of determining if the series id
should be included or not. The AND condition used false correctly so did
not have to be changed.
If a tag did not exist and `!=` or `!~` were used, it would return false
even though the neither a field or a tag equaled those values. This has
now been modified to correctly return the correct series ids and the
correct condition.
Also fixed a panic that would occur when a tag caused a field access to
become unnecessary. The filter using the field access still got created
and used even though it was unnecessary, resulting in an attempted
access to a non-initialized map.
Fixes#5152 and a bunch of other miscellaneous issues.
After reading the initial buffer, ORDER BY desc would read the next
block into the buffer and only read the first element. It's because the
code that was copied from the ascending cursor wasn't modified correctly
to set the position to the last element in the buffer.
The buffer size has also been lowered from 1000 to 10 to match with the
ascending cursor for performance with limit queries.
Fixes#6055.
This commit adds an `IteratorStats` that holds aggregate
iterator processing information. A method is also added to
`Iterator` to return the stats:
Stats() influxql.IteratorStats
The remote iterators will also emit their stats in the point
stream upon first connection, on a given interval, and then
finally once the last point has been sent.
The TSM writer uses a bufio.Writer that needs to be flushed before
it's closed. If the flush fails for some reason, the error is not
handled by the defer and the compactor continues on as if all is good.
This can create files with truncated indexes or zero-length TSM files.
Fixes#5889
Use of the iterator is spread out into both `IteratorCreators` and
inside of the iterators themselves. Part of the interrupt must be
handled inside of the engine so it stops trying to emit points when an
interrupt is found and another part of the interrupt has to happen when
combining the iterators so it doesn't just start reading the next shard.
These were all b1/bz1 settings that no longer have any effect:
- {Default,}MaxWALSize
- {Default,}WALFlushInterval
- {Default,}WALPartitionFlushDelay
- {Default,WAL}ReadySeriesSize
- {Default,WAL}CompactionThreshold
- {Default,WAL}MaxSeriesSize
- {Default,WAL}FlushColdInterval
- {Default,WAL}PartitionSizeThreshold
Internal system series start with an underscore prefix but
restricting this prevents users who already use an underscore
prefix in their series names.
Fixes#5870
A deadlock occurs under write load if a backup is run in between the
time when a snapshot compactions has snapshotted the cache and successfully
written it to disk. The issus is that the second snapshot call will block
on the commit lock while it is holding the engine write lock. This causes
all writes to block as well as prevents the currently runnign snapshot
compaction from completing because it needs to acquire a read-lock.
This PR removes the commit lock and just returns an error if a snapshot is
in progress to all any locks being held to be released. The caller can determine
whether to retry or giveup.
Slices of tsm1.Value interfaces are only ever used with all the same
types, and the previous code would switch on the type returned from a
call to Value(), which allocated and returned an interface{} object for
the underlying value.
This change instead type-switches on the tsm1.Value object itself,
allowing it direct access to the underlying value field, eliminating the
unecessary allocations.
This commit moves the `tsdb.Store.ExpandSources()` function onto
the `influxql.IteratorCreator` and provides support for issuing
source expansion across a cluster.
`SHOW TAG VALUES` output has been modified to print the measurement name
for every measurement and to return the output in two columns: key and
value. An example output might be:
> SHOW TAG VALUES WITH KEY IN (host, region)
name: cpu
---------
key value
host server01
region useast
name: mem
---------
key value
host server02
region useast
`measurementsByExpr` has been taught how to handle reserved keys (ones
with an underscore at the beginning) to allow reusing that function and
skipping over expressions that don't matter to the call.
Fixes#5593.
... by extracting the db/rp from the given path.
Now that the code has "standardized" on extracting db/rp this way, the
ShardLocation struct is no longer necessary and thus has been removed.
We're back on the previous style of passing the path and walPath to
NewShard.
The current go compiler at the tip of the go master (1d5001af) has a modified implementation of
testing.quick.Check that now generates nil slices as test data. (See: https://gophers.slack.com/archives/general/p14567053570110). The existing tests expect round tripping to work in this case
but it does not. So, in these cases we change the expectation to reflect actual behaviour.
This needs to be checked for reasonableness.
This commit updates tsdb.Shard to contain a ShardConfig and updates
tsdb.Store to directly reference a map of tsdb.Shard rather than the
previous tsdb.shardLocation abstraction.
Previously, the for loop at the end of the method assumed that all entries
had been deduplicated, including the entry discovered in the snapshot.
However, this wasn't actually true. With this change, we make it true.
Signed-off-by: Jon Seymour <jon@wildducktheories.com>
Consider the write sequence: 6,1,snapshot,7,2.
The hot cache gets deduplicated, so is 2,7.
Now consider the test if 1 >= 2, this is false, so needSort is not set to true.
The problem is the implicit assumption that the snapshot is always sorted
by the time that merged() runs, but this may not be true.
Signed-off-by: Jon Seymour <jon@wildducktheories.com>
Previously, we needed a write lock on the cache because it was the
only lock we had available to guard updates to entry.values and
entry.needSort.
However, now we have a entry-scoped lock for this purpose, we don't
need the cache write lock for this purpose. Since merged() doesn't
modify the .store or the c.snapshot.sort, there is no need for
a write lock on the cache to protect the cache.
So, we don't need to escalate here - we simply rely on the entry lock
to protect the entries we are iterating over.
Signed-off-by: Jon Seymour <jon@wildducktheories.com>
Based on @jwilder's alternative to the 'dirty' slice that featured
in previous iterations of this fix.
Suggested-by: Jason Wilder <jason@influxdb.com>
Signed-off-by: Jon Seymour <jon@wildducktheories.com>
Currently two compactors can execute Engine.WriteSnapshot at once.
This isn't thread safe since both threads want to make modifications to
Cache.snapshot at the same time.
This commit introduces a lock which is acquired during Snapshot() and
released during ClearSnapshot(), ensuring that at most one thread
executes within Engine.WriteSnapshot() at once.
To ensure that we always release this lock, but only release the
snapshot resources on a successful commit, we modify ClearSnapshot() to
accept a boolean which indicates whether the write was successful or not
and guarantee to call this function if Snapshot() has been called.
Signed-off-by: Jon Seymour <jon@wildducktheories.com>
There are two tests that show two different one vulnerability.
One test shows that Cache.Deduplicate modifies entries in a snapshot's
store without a lock while cache readers are deduplicating those same
entries while correctly locked.
A second test shows that two threads trying to execute the methods
that Engine.WriteSnapshot calls will cause concurrent, unsynchronized
mutating access to the snapshot's store and entries.
The tests fail at this commit and are fixed by subsequent commits.
Signed-off-by: Jon Seymour <jon@wildducktheories.com>
Ben Johnson
Jonathan A. Sternberg
Jason Wilder
Jason Wilder
Mark Rushakoff
Jonathan A. Sternberg
Cory LaNou
Joe LeGasse
Edd Robinson
Jon Seymour
Mark Rushakoff
Jason Wilder