Fixes a race condition where COMPRESSOR_NAME in zstd.cc could be
initialized before compressor::namespace_prefix due to undefined
global variable initialization order across translation units. This
was causing ZstdCompressor to be unregistered in release builds,
making it impossible to create tables with Zstd compression.
Replace the global namespace_prefix variable with a function that
returns the fully qualified compressor name. This ensures proper
initialization order and fixes the registration of the ZstdCompressor.
Fixesscylladb/scylladb#22444
Signed-off-by: Kefu Chai <kefu.chai@scylladb.com>
Closesscylladb/scylladb#22451
(cherry picked from commit 4a268362b9)
Closesscylladb/scylladb#22510
zstd.h is a header provided by libzstd, so let's include it with
brackets, more consistent this way.
Signed-off-by: Kefu Chai <kefu.chai@scylladb.com>
Closesscylladb/scylladb#19538
The zstd implementation of `compressor` has a separate decompression and
compression context per instance. This is unreasonably wasteful. One
decompression buffer and one compression buffer *per shard* is enough.
The waste is significant. There might exist thousands of SSTable readers, each
containing its own instance of `compressor` with several hundred KiB worth of
unneeded buffers. This adds up to gigabytes of wasted memory and gigapascals
of allocator pressure.
This patch modifies the implementation of zstd_processor so that all its
instances on the shard share their contexts.
Fixes#11733
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
Enable creating shared_ptr<BaseClass> in nonstatic_class_registry
using BaseClass::ptr_type and use that for
abstract_replication_strategy.
While at it, also clean up compressor with that respect
to define compressor::ptr_type as shared_ptr<compressor>
thus simplifying compressor_registry.
Signed-off-by: Benny Halevy <bhalevy@scylladb.com>
This adds the option to compress sstables using the Zstandard algorithm
(https://facebook.github.io/zstd/).
To use, pass 'sstable_compression': 'org.apache.cassandra.io.compress.ZstdCompressor'
to the 'compression' argument when creating a table.
You can also specify a 'compression_level'. See Zstd documentation for the available
compression levels.
Resolves#2613.
Signed-off-by: Kamil Braun <kbraun@scylladb.com>
