Currently unregister_inactive_read for other shards is moved
to the background with nothing keep the respective
reader_concurrency_semaphore around.
This change runs the loop in parallel_for_each
so that we don't have to serially wait on all of them
but rather they can run in parallel on all shards, but
all are waited on via the returned future<>.
Signed-off-by: Benny Halevy <bhalevy@scylladb.com>
Currently only if the reader_meta is in the saved state
we unregister its inactive_read, yet it is possible
that it will hold an inactive_read also in the lookup state.
To cover all cases, rather than testing the reader_state,
unregister if the inactive_read_handle is engaged.
Signed-off-by: Benny Halevy <bhalevy@scylladb.com>
As it can't throw. This is needed to simplify the following
patch that will always close the reader in read_page.
Signed-off-by: Benny Halevy <bhalevy@scylladb.com>
return reader lifecycle policy's destroy_reader future
so it can be waited on by caller (multishard_combining_reader::close).
Signed-off-by: Benny Halevy <bhalevy@scylladb.com>
Move the logic in ~foreign_reader to close()
to wait on the read_ahead future and close the underlying
reader on the remote shard. Still call close in the background
in ~foreign_reader if destroyed without closing to keep the current
behavior, but warn about it, until it's proved to be unneeded.
Also, added on_iternal_error in close if _read_ahead_future
is engaged but _reader is not, since this must never happen
and we wait on the _read_ahead_future without the _reader.
Signed-off-by: Benny Halevy <bhalevy@scylladb.com>
These will be called by merging_reader::close via
mutation_fragment_merger::close in the following patches.
Signed-off-by: Benny Halevy <bhalevy@scylladb.com>
Such that the holder, that is responsible for closing the
read_context before destroying it, holds it uniquely.
cache_flat_mutation_reader may be constructed either
with a read_context&, where it knows that the read_context
is owned externally, by the caller, or it could
be constructed with a std::unique_ptr<read_context> in
which case it assumes ownership of the read_context
and it is now responsible for closing it.
Signed-off-by: Benny Halevy <bhalevy@scylladb.com>
Note that scanning_and_populating_reader::read_next_partition
now closes the current reader unconditionally
and before assigning a new reader. This should be an improvement
since we want to release resources the reader resources as early
as possible, certainly before allocating new resources.
Signed-off-by: Benny Halevy <bhalevy@scylladb.com>
use the newly introduced reassign method to first
close the flat_mutation_reader_opt before assigning it with
a new reader.
Signed-off-by: Benny Halevy <bhalevy@scylladb.com>
Close _delegate if it's engaged both in the close() method
and when ever it is currently reset by _delegate = {}.
Signed-off-by: Benny Halevy <bhalevy@scylladb.com>
We don't own _source therefore do not close it.
That said, we still need to make sure that the reversing reader
itself is closed to calm down the check when it's destroyed.
Signed-off-by: Benny Halevy <bhalevy@scylladb.com>
The underlying reader is owned by the caller if it is moved to it,
but not if it was constructed with a reference to the underlying reader.
Close the underlying reader on close() only in the former case.
Signed-off-by: Benny Halevy <bhalevy@scylladb.com>
Close both the _index_reader and _context, if they are engaged.
Warn and ignore any erros from close as it may be called either
from the destructor or from f_m_r close.
Call close() for closing in the background if needed when destroyed
and warn about.
Signed-off-by: Benny Halevy <bhalevy@scylladb.com>
We'd like that to simplify the soon-to-be-introduced
sstable_mutation_reader::close error handling path.
close_index_list can be marked noexcept since parallel_for_each is,
with that index_reader::close can be marked noexcept too.
Note that since reader close can not fail
both lower and upper bounds are closed (since
closing lower_bound cannot fail).
Signed-off-by: Benny Halevy <bhalevy@scylladb.com>
