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
The problem is that `std::chrono::duration_cast` is not `noexcept`. As a result,
`timestamp_clock` is actually a model of `Clock` and not `TrivialClock`.
This change fixes the dependencies between the clock implementation headers. All
the clocks share the common clock offset, but are otherwise independent (though
the `db_clock` does depend on `gc_clock` for time point conversions).
Currently server-side timestamps use a clock with millisecond
precision. Timestamps have microsecond resolution, with lower bits
used to serialize mutations originating from given client.
Timestamps for column drops always use just the millisecond base. A
column drop which is executed after an insert may thus be given lower
timestamp than the insert, even when the two are serialized on the
client side over same connection.
Use microsecond precision to reduce chances of that event.
This is supposed to fix sporadic failures of
schema_test.py:TestSchema.drop_column_queries_test dtest.
Message-Id: <1482343119-27698-1-git-send-email-tgrabiec@scylladb.com>
Replace db_clock::now_in_usec() and db_clock::now() * 1000 accesses
where the intent is to create a new auto-generate cell timestamp with
a call to new_timestamp(). Now the knowledge of how to create timestamps
is in a single place.
