* Avoid deadlock when processing duplicate series record
`processWALSamples()` needs to be able to send on its output channel
before it can read the input channel, so reads to allow this in case the
output channel is full.
Signed-off-by: Bryan Boreham <bjboreham@gmail.com>
* processWALSamples: update comment
Previous text seems to relate to an earlier implementation.
Signed-off-by: Bryan Boreham <bjboreham@gmail.com>
Co-authored-by: Bryan Boreham <bjboreham@gmail.com>
* BenchmarkLoadWAL: close WAL after use
So that goroutines are stopped and resources released
Signed-off-by: Bryan Boreham <bjboreham@gmail.com>
* BenchmarkLoadWAL: make series IDs co-prime with #workers
Series are distributed across workers by taking the modulus of the
ID with the number of workers, so multiples of 100 are a poor choice.
Signed-off-by: Bryan Boreham <bjboreham@gmail.com>
* BenchmarkLoadWAL: simulate mmapped chunks
Real Prometheus cuts chunks every 120 samples, then skips those samples
when re-reading the WAL. Simulate this by creating a single mapped chunk
for each series, since the max time is all the reader looks at.
Signed-off-by: Bryan Boreham <bjboreham@gmail.com>
* Fix comment
Signed-off-by: Bryan Boreham <bjboreham@gmail.com>
* Remove series map from processWALSamples()
The locks that is commented to reduce contention in are now sharded
32,000 ways, so won't be contended. Removing the map saves memory and
goes just as fast.
Signed-off-by: Bryan Boreham <bjboreham@gmail.com>
* loadWAL: Cache the last mmapped chunk time
So we can skip calling append() for samples it will reject.
Signed-off-by: Bryan Boreham <bjboreham@gmail.com>
* Improvements from code review
Signed-off-by: Bryan Boreham <bjboreham@gmail.com>
* Full stops and capitals on comments
Signed-off-by: Bryan Boreham <bjboreham@gmail.com>
* Cache max time in both places mmappedChunks is updated
Including refactor to extract function `setMMappedChunks`, to reduce
code duplication.
Signed-off-by: Bryan Boreham <bjboreham@gmail.com>
* Update head min/max time when mmapped chunks added
This ensures we have the correct values if no WAL samples are added for
that series.
Note that `mSeries.maxTime()` was always `math.MinInt64` before, since
that function doesn't consider mmapped chunks.
Signed-off-by: Bryan Boreham <bjboreham@gmail.com>
* Avoid deadlock when processing duplicate series record
`processWALSamples()` needs to be able to send on its output channel
before it can read the input channel, so reads to allow this in case the
output channel is full.
Signed-off-by: Bryan Boreham <bjboreham@gmail.com>
* processWALSamples: update comment
Previous text seems to relate to an earlier implementation.
Signed-off-by: Bryan Boreham <bjboreham@gmail.com>