Introduce file_copy_method setting. It can be set to either COPY (the default) or CLONE if the system supports it. CLONE causes callers of copydir(), currently CREATE DATABASE ... STRATEGY=FILE_COPY and ALTER DATABASE ... SET TABLESPACE = ..., to use copy_file_range (Linux, FreeBSD) or copyfile (macOS) to copy files instead of a read-write loop over the contents.
CLONE gives the kernel the opportunity to share block ranges on copy-on-write file systems and push copying down to storage on others, depending on configuration. On some systems CLONE can be used to clone large databases quickly with CREATE DATABASE ... TEMPLATE=source STRATEGY=FILE_COPY. Other operating systems could be supported; patches welcome. Co-authored-by: Nazir Bilal Yavuz <byavu...@gmail.com> Reviewed-by: Robert Haas <robertmh...@gmail.com> Reviewed-by: Ranier Vilela <ranier...@gmail.com> Discussion: https://postgr.es/m/CA%2BhUKGLM%2Bt%2BSwBU-cHeMUXJCOgBxSHLGZutV5zCwY4qrCcE02w%40mail.gmail.com Branch ------ master Details ------- https://git.postgresql.org/pg/commitdiff/f78ca6f3ebbbff8c675c34b8ee61047223073866 Modified Files -------------- doc/src/sgml/config.sgml | 38 ++++++++++++ doc/src/sgml/ref/alter_database.sgml | 3 +- doc/src/sgml/ref/create_database.sgml | 4 +- src/backend/storage/file/copydir.c | 80 ++++++++++++++++++++++++- src/backend/utils/activity/wait_event_names.txt | 1 + src/backend/utils/misc/guc_tables.c | 22 +++++++ src/backend/utils/misc/postgresql.conf.sample | 4 ++ src/include/storage/copydir.h | 9 +++ src/tools/pgindent/typedefs.list | 1 + 9 files changed, 159 insertions(+), 3 deletions(-)
