Commit Graph

2 Commits

Author SHA1 Message Date
Avi Kivity
fcb8d040e8 treewide: use Software Package Data Exchange (SPDX) license identifiers
Instead of lengthy blurbs, switch to single-line, machine-readable
standardized (https://spdx.dev) license identifiers. The Linux kernel
switched long ago, so there is strong precedent.

Three cases are handled: AGPL-only, Apache-only, and dual licensed.
For the latter case, I chose (AGPL-3.0-or-later and Apache-2.0),
reasoning that our changes are extensive enough to apply our license.

The changes we applied mechanically with a script, except to
licenses/README.md.

Closes #9937
2022-01-18 12:15:18 +01:00
Nadav Har'El
ae51fef57c cql-pytest: add tests for estimated partition count
In issue #9083 a user noted that whereas Cassandra's partition-count
estimation is accurate, Scylla's (rewritten in commit b93cc21) is very
inaccurate. The tests introduce here, which all xfail on Scylla, confirm
this suspicion.

The most important tests are the "simple" tests, involving a workload
which writes N *distinct* partitions and then asks for the estimated
partition count. Cassandra provides accurate estimates, which grow
more accurate with more partitions, so it passes these tests, while
Scylla provides bad estimates and fails them.

Additional tests demonstrate that neither Scylla nor Cassandra
can handle anything beyond the "simple" case of distinct partitions.
Two tests which xfail on both Cassandra and Scylla demonstrate that
if we write the same partitions to multiple sstables - or also delete
partitions - the estimated partition counts will be way off.

Refs #9083

Signed-off-by: Nadav Har'El <nyh@scylladb.com>
Message-Id: <20210726211315.1515856-1-nyh@scylladb.com>
2021-08-05 08:50:19 +02:00