The specialized version of sample add to the ring:
func addH(s hSample, buf []hSample, r *sampleRing) []hSample
func addFH(s fhSample, buf []fhSample, r *sampleRing) []fhSample
already correctly copy histogram samples from the reused hReader, fhReader
buffers, but the generic version does not. This means that the
data is overwritten on the next read if the sample ring has seen histogram
and float samples at the same time and switched to generic mode.
The `genericAdd` function (which was commented anyway) is by now quite
different from the specialized functions so that this commit deletes
it.
Signed-off-by: György Krajcsovits <gyorgy.krajcsovits@grafana.com>
Add a chunk size limit in bytes
This creates a hard cap for XOR chunks of 1024 bytes.
The limit for histogram chunk is also 1024 bytes, but it is a soft limit as a histogram has a dynamic size, and even a single one could be larger than 1024 bytes.
This also avoids cutting new histogram chunks if the existing chunk has fewer than 10 histograms yet. In that way, we are accepting "jumbo chunks" in order to have at least 10 histograms in a chunk, allowing compression to kick in.
Signed-off-by: Justin Lei <justin.lei@grafana.com>
György Krajcsovits