Add a boolean sync-rcu repos.conf setting that behaves as follows:
sync-rcu = yes|no
Enable read-copy-update (RCU) behavior for sync operations. The
current latest immutable version of a repository will be referenced
by a symlink found where the repository would normally be located
(see the location setting). Repository consumers should resolve
the cannonical path of this symlink before attempt to access
the repository, and all operations should be read-only, since
the repository is considered immutable. Updates occur by atomic
replacement of the symlink, which causes new consumers to use the
new immutable version, while any earlier consumers continue to
use the cannonical path that was resolved earlier. This option
requires sync-allow-hardlinks and sync-rcu-store-dir options to
be enabled, and currently also requires that sync-type is set
to rsync. This option is disabled by default, since the symlink
usage would require special handling for scenarios involving bind
mounts and chroots.
sync-rcu-store-dir
Directory path reserved for sync-rcu storage. This directory must
have a unique value for each repository (do not set it in the
DEFAULT section). This directory must not contain any other files
or directories aside from those that are created automatically
when sync-rcu is enabled.
sync-rcu-spare-snapshots = 1
Number of spare snapshots for sync-rcu to retain with expired
ttl. This protects the previous latest snapshot from being removed
immediately after a new version becomes available, since it might
still be used by running processes.
sync-rcu-ttl-days = 7
Number of days for sync-rcu to retain previous immutable snapshots
of a repository. After the ttl of a particular snapshot has
expired, it will be remove automatically (the latest snapshot
is exempt, and sync-rcu-spare-snapshots configures the number of
previous snapshots that are exempt). If the ttl is set too low,
then a snapshot could expire while it is in use by a running
process.
Zac Medico (4):
Implement asyncio.iscoroutinefunction for compat_coroutine
Add _sync_decorator module
rsync: split out repo storage framework
Add sync-rcu support for rsync (bug 662070)
lib/portage/repository/config.py | 36 ++-
lib/portage/repository/storage/__init__.py | 0
.../repository/storage/hardlink_quarantine.py | 95 ++++++++
lib/portage/repository/storage/hardlink_rcu.py | 251 +++++++++++++++++++++
lib/portage/repository/storage/inplace.py | 49 ++++
lib/portage/repository/storage/interface.py | 87 +++++++
lib/portage/sync/controller.py | 1 +
lib/portage/sync/modules/rsync/rsync.py | 85 ++-----
lib/portage/sync/syncbase.py | 33 +++
.../tests/util/futures/test_compat_coroutine.py | 14 ++
lib/portage/util/futures/_asyncio/__init__.py | 14 ++
lib/portage/util/futures/_sync_decorator.py | 54 +++++
lib/portage/util/futures/compat_coroutine.py | 12 +
man/portage.5 | 35 +++
14 files changed, 700 insertions(+), 66 deletions(-)
create mode 100644 lib/portage/repository/storage/__init__.py
create mode 100644 lib/portage/repository/storage/hardlink_quarantine.py
create mode 100644 lib/portage/repository/storage/hardlink_rcu.py
create mode 100644 lib/portage/repository/storage/inplace.py
create mode 100644 lib/portage/repository/storage/interface.py
create mode 100644 lib/portage/util/futures/_sync_decorator.py
--
2.16.4
