panic: error opening new segment file for wal: open /var/folders/lj/vlbynqp52pxdxxlxx64j6bk80000gn/T/tsm1-test709000715/_00002.wal: no such file or directory
goroutine 8 [running]:
github.com/influxdb/influxdb/tsdb/engine/tsm1.(*Log).writeToLog(0xc820098500, 0x1, 0xc8201584b0, 0x1c, 0x45, 0x0, 0x0)
/Users/jason/go/src/github.com/influxdb/influxdb/tsdb/engine/tsm1/wal.go:427 +0xc19
When rewriting a tsm file, a panice on the Values slice could happen
if there were no values in the slice and the conditions of the rewrite
causes DecodeAndCombine to be called with the empty slice. This could
happen is the sizes of the points new values was equal to
the MaxPointsInBlock config options and there were no future blocks after
the current one being written.
When this happens, DecodeAndCombine returns a zero length remaining values
slice which is passed back into DecodeAndCombine one last time. In this case,
we now just return the original block since there is nothing new to combine.
Fixes#4444#4365
This will help large integer counters type fields that increment by
small amounts over time. Instead of storing the larger raw value
in a compressed format, we store the difference from the prior value
in compressed format which allows the value to be stored using
fewer bits.
influx_inpsect uncovered some scenarios where timestamps could be stored using
run-length encoding but were being stored using simple8 which uses more space.
If DecodeSameTypeBlock is called on on an empty Values slice, it would
panic with an index out of bounds error. This func can actually be removed
because DecodeBlock can determine what type of values are encoded already.
This will still panic if the block cannot be decoded due to other reasons.
Fixes#4365
If similar float values were encoded, the number of leading bits would
overflow the 5 available bits to store them (e.g. store 33 in 5 bits). When
decoding, the values after the overflowed value would spike to very large and
small values.
To prevent the overflow, we clamp the value to 31 which is the maximum
number of leading zero bits we can encoded.
Fixes#4357
Will make it less error-prone to add new encodings int the future
since each encoder has it's set of constants. There are some placeholder
contants for uncompressed encodings which are not in all encoder currently.