fixes#17440
While encoding or decoding corrupt data, the current behaviour is to `panic`.
This commit replaces the `panic` with `error` to be propagated up to the calling `iterator`.
To avoid overwriting other `error`, iterators now wraps a `TSMErrors` which contains ALL the encountered errors.
TSMErrors itself implements `Error()`, the returned string contains all the error msgs, separated by "," delimiter.
StringArrayEncodeAll will panic if the total length of strings
contained in the src slice is > 0xffffffff. This change adds a unit
test to replicate the issue and an associated fix to return an error.
This also raises an issue that compactions will be unable to make
progress under the following condition:
* multiple string blocks are to be merged to a single block and
* the total length of all strings exceeds the maximum block size that
snappy will encode (0xffffffff)
The observable effect of this is errors in the logs indicating a
compaction failure.
Fixes#13687
* introduced UnsignedValue type
* leveraged existing int64 compression algorithms (RLE, Simple 8B)
* tsm and WAL can read and write UnsignedValue
* compaction is aware of UnsignedValue
* unsigned support to model, cursors and write points
NOTE: there is no support to create unsigned points, as the line
protocol has not been modified.
This switches compactions to use type values (FloatValues) from the
generic Values type. It avoids a bunch of allocations where each value
much be converted from a specific type to an interface{}.