Add include statements to satisfy dependencies.
Delete, now unneeded, include directives from the upper level
source files.
Signed-off-by: Benny Halevy <bhalevy@scylladb.com>
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
So far commitlog was using contiguous buffers for storing the data that
is about to be written to disk. It was able to coalesce small writes so
that multiple small mutations would use the same buffer, but if a
muation was large the commitlog would attempt to allocate a single,
appropriately large buffer. This excessively stresses the memory
allocator and may cause memory fragmentation to become an issue. The
solution is to use fixed-size buffers of 128 kB, which is the standard
buffer size in Scylla and keep large values fragmented.
It is safe to copy column_mapping accros shards. Such guarantee comes at
the cost of performance.
This patch makes commitlog_entry_writer use IDL generated writer to
serialise commitlog_entry so that column_mapping is not copied. This
also simplifies commitlog_entry itself.
Performance difference tested with:
perf_simple_query -c4 --write --duration 60
(medians)
before after diff
write 79434.35 89247.54 +12.3%
* seastar 2b55789...5b7252d (3):
> Merge "rpc: serialize large messages into fragmented memory" from Gleb
> Merge "Print backtrace on SIGSEGV and SIGABRT" from Tomasz
> test_runner: avoid nested optionals
Includes patch from Gleb to adapt to seastar changes.
