Revert commit 0faa40e4 to increase the disk space consumed by the
metabase in favor of the speed of index updates.
Signed-off-by: Leonard Lyubich <leonard@nspcc.ru>
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>
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>
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 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>
