There are certain errors which are not expected during usual node
operation and which tell us that something is wrong with the shard.
To prevent possible data corruption, move shard in read-only mode after
amount of errors exceeded some threshold. By default no actions are performed.
Signed-off-by: Evgenii Stratonikov <evgeniy@nspcc.ru>
There is a need to disable execution of local data operation on storage
engine in runtime. If storage engine ops are blocked, node will act like
always but all local object operations will be denied.
Implement `BlockExecution` / `ResumeExecution` methods on `StorageEngine`
which blocks / resumes the execution of data ops. Wait for the completion of
all operations executed at the time of the call. Return error passed to
`BlockExecution` from all data-related methods until `ResumeExecution` call.
Make `Close` to block operations as well.
Signed-off-by: Leonard Lyubich <leonard@nspcc.ru>
Make `StorageEngine` to use non-blocking worker pools with the same
(configurable) size for PUT operation. This allows you to switch to using
more free shards when overloading others, thereby more evenly distributing
the write load.
Signed-off-by: Leonard Lyubich <leonard@nspcc.ru>
Implement Put/Get/GetRange/Select/SelectAll functions over storage
engine. These functions are going to be used by Object service.
Signed-off-by: Leonard Lyubich <leonard@nspcc.ru>
In previous implementation each operation on local storage
locked engine mutex. This was done under the assumption that
the weights of the shards change as a result of write operations.
With the transition to static weights of shards, it is no longer
necessary to lock the global mutex during the execution of operations.
However, since the set of engine shards is dynamic, there is still a
need to control multiple access to this set. The same mutex is used
for synchronization.
Signed-off-by: Leonard Lyubich <leonard@nspcc.ru>
