Review requested: Add downgradesstables

["Claude Warren, Jr via dev" <de...@cassandra.apache.org>]

https://github.com/apache/cassandra/pull/2045

https://issues.apache.org/jira/browse/CASSANDRA-8928

This is a work in progress and I am looking for some feedback.

This fix appears to work correctly. But I think the placement of the v3
directory is probably not the best and perhaps should be moved under the
db/compaction directory where the Downgrader code is.

Suggestions appreciated.
The changes are:

*added*

   - db/compaction/Downgrader
   - tools/StandAloneDowngrader
   - getNextsstableID to ColumnFamilyStore
   - DOWNGRADE_SSTABLES to OperationType
   - hasMaxCompressedLength to CompressionMetadata constructor and
   associated calls.
   - V3 to SSTableFormat.Type
   - added io/sstable/format/big/v3 directory containing BigFormatV3,
   BigTableReaderV3, BitTableScannerV3, BitTableWriterV3

*modified*

   - CompressionMetadata to skip output of maxCompressedLength if not
   supported

*notes*

   - io/sstable/format/big/v3 classes are the V3 classes modified as
   necessary to run within the V4 environment.

Re: Review requested: Add downgradesstables

[Jacek Lewandowski <le...@gmail.com>]

Hi,

The feature looks useful to me

Could you add the pull request address to the ticket and summarize the
features it is going to provide?

Thank you,
- - -- --- ----- -------- -------------
Jacek Lewandowski


On Fri, Dec 9, 2022 at 10:13 AM Claude Warren, Jr via dev <
dev@cassandra.apache.org> wrote:

> https://github.com/apache/cassandra/pull/2045
>
> https://issues.apache.org/jira/browse/CASSANDRA-8928
>
> This is a work in progress and I am looking for some feedback.
>
> This fix appears to work correctly. But I think the placement of the v3
> directory is probably not the best and perhaps should be moved under the
> db/compaction directory where the Downgrader code is.
>
> Suggestions appreciated.
> The changes are:
>
> *added*
>
>    - db/compaction/Downgrader
>    - tools/StandAloneDowngrader
>    - getNextsstableID to ColumnFamilyStore
>    - DOWNGRADE_SSTABLES to OperationType
>    - hasMaxCompressedLength to CompressionMetadata constructor and
>    associated calls.
>    - V3 to SSTableFormat.Type
>    - added io/sstable/format/big/v3 directory containing BigFormatV3,
>    BigTableReaderV3, BitTableScannerV3, BitTableWriterV3
>
> *modified*
>
>    - CompressionMetadata to skip output of maxCompressedLength if not
>    supported
>
> *notes*
>
>    - io/sstable/format/big/v3 classes are the V3 classes modified as
>    necessary to run within the V4 environment.
>
>