In the previous implementation of the metabase, it was necessary to write
virtual objects to the primary index to be able to select them. In this
approach, virtual objects can be obtained directly using Head operation.
This has a side effect in handling object operations that do not expect to
receive a virtual object header in a single operation. With recent changes,
it is no longer necessary to have records of virtual objects in the primary
index, so this no longer happens for system integrity.
Signed-off-by: Leonard Lyubich <leonard@nspcc.ru>
Fix a bug in the selection when removed object that matches search query
provoked the return of an empty result.
Signed-off-by: Leonard Lyubich <leonard@nspcc.ru>
Fix a bug in the selection when an object could be added to the result after
a mismatch in the previous filter.
Signed-off-by: Leonard Lyubich <leonard@nspcc.ru>
In the previous implementation of the metabase, the unique value of the
header was assigned a bucket, the elements of which were leaves with a
key-address and an empty value. This approach was relatively efficient in
terms of write speed. However, a large number of buckets led to a rapid
increase in the database volume (~4GB for 100K objects with unique
attributes). An approach is presented with storing indexes on the value of
headers in the leaves of the tree, where the keys are the unique values of
the header, and the values are a serialized list of addresses (gob
encoding is temporarily used for serialization).
The new approach gave a good result in saving space (~350MB), however, it
significantly reduced the write speed with an increase in the number of
objects (~ 80x after 100K objects).
Signed-off-by: Leonard Lyubich <leonard@nspcc.ru>
The previous metabase implementation took an exclusionary approach: filters
narrowed the set of all objects to those that match all filters. An
inclusive approach is presented. In it, when traversing the indexed headers,
the object becomes a candidate for selection. If at least one of the
subsequent filters is not passed, the object ceases to be a candidate. At
the end of the traversal, the remaining candidates are added to the
resulting sample. The borderline case of no filters is handled in a special
way: all stored objects are added to the resulting selection.
Presented inclusive approach showed better performance in most scenarios
(although not all).
Signed-off-by: Leonard Lyubich <leonard@nspcc.ru>
In previous metabase implementation the absence of an attribute presented in
the search filter did not exclude the object from the result. Change this
behavior to exclude the object from the result.
Signed-off-by: Leonard Lyubich <leonard@nspcc.ru>
Replace meta Bucket with meta.DB instance in local storage implementation.
Adopt all dependent components to new local storage.
Signed-off-by: Leonard Lyubich <leonard@nspcc.ru>
Process parent objects in Put method. Headers of parent object are stored as
regular leaf objects in metabase from now. Build indexes for ROOT, LEAF and
CHILDFREE properties.
Signed-off-by: Leonard Lyubich <leonard@nspcc.ru>
Implement Delete method on DB structure that adds deleted addresses to
tombstone index. Do not attach addresses from tombstone index to Select
result. Return error from Get method if address is presented in tombstone
index.
Signed-off-by: Leonard Lyubich <leonard@nspcc.ru>
Implement bolt-based metabase that is going to be used in local object
storage. Implement Put/Get/Select methods.
Signed-off-by: Leonard Lyubich <leonard@nspcc.ru>
