The DumpXXX() methods were always documented as internal and
unsupported. However, now they are being removed from the
public top-level API. They are still available on the internal
IndexReader, which can be accessed using the Advanced() method.
The DocCount() and DumpXXX() methods on the internal index
have moved to the internal index reader, since they logically
operate on a snapshot of an index.
the motivation for this commit is long and detailed and has been
documented externally here:
https://gist.github.com/mschoch/5cc5c9cf4669a5fe8512cb7770d3c1a2
the core of the changes are:
1. recognize that collector/searcher need only a fixed number
of DocumentMatch instances, and this number can be determined
from the structure of the query, not the size of the data
2. knowing this, instances can be allocated in bulk, up front
and they can be reused without locking (since all search
operations take place in a single goroutine
3. combined with previous commits which enabled reuse of
the IndexInternalID []byte, this allows for no allocation/copy
of these bytes as well (by using DocumentMatch Reset() method
when returning entries to the pool
instead of separate DocumentMatch/DocumentMatchInternal
rules are simple, everything operates on the IndexInternalID field
until the results are returned, then ID is set correctly
the IndexInternalID field is not exported to JSON
index id's are now opaque (until finally returned to top-level user)
- the TermFieldDoc's returned by TermFieldReader no longer contain doc id
- instead they return an opaque IndexInternalID
- items returned are still in the "natural index order"
- but that is no longer guaranteed to be "doc id order"
- correct behavior requires that they all follow the same order
- but not any particular order
- new API FinalizeDocID which converts index internal ID's to public string ID
- APIs used internally which previously took doc id now take IndexInternalID
- that is DocumentFieldTerms() and DocumentFieldTermsForFields()
- however, APIs that are used externally do not reflect this change
- that is Document()
- DocumentIDReader follows the same changes, but this is less obvious
- behavior clarified, used to iterate doc ids, BUT NOT in doc id order
- method STILL available to iterate doc ids in range
- but again, you won't get them in any meaningful order
- new method to iterate actual doc ids from list of possible ids
- this was introduced to make the DocIDSearcher continue working
searchers now work with the new opaque index internal doc ids
- they return new DocumentMatchInternal (which does not have string ID)
scorerers also work with these opaque index internal doc ids
- they return DocumentMatchInternal (which does not have string ID)
collectors now also perform a final step of converting the final result
- they STILL return traditional DocumentMatch (with string ID)
- but they now also require an IndexReader (so that they can do the conversion)
at the time you create the term field reader, you can specify
that you don't need the term freq, the norm, or the term vectors
in that case, the index implementation can choose to not return
them in its subsequently returned values
this is advisory only, some simple implementations may ignore this
and continue to return the values anyway (as the current impl of
upside_down does today)
this change will allow future index implementations the
opportunity to do less work when it isn't required
The UpsideDownCouchTermFieldReader.Next() only needs the doc ID from
the key, so this change provides a specialized parseKDoc() method for
that optimization.
Additionally, fields in various structs are more 64-bit aligned, in an
attempt to reduce the invocations of runtime.typedmemmove() and
runtime.heapBitsBulkBarrier(), which the go compiler seems to
automatically insert to transparently handle misaligned data.
This optimization changes the index.TermFieldReader.Next() interface
API, adding an optional, pre-allocated *TermFieldDoc parameter, which
can help prevent garbage creation.
This optimization changes the search.Search.Next() interface API,
adding an optional, pre-allocated *DocumentMatch parameter.
When it's non-nil, the TermSearcher and TermQueryScorer will use that
pre-allocated *DocumentMatch, instead of allocating a brand new
DocumentMatch instance.
In the index/store package
introduce KVReader
creates snapshot
all read operations consistent from this snapshot
must close to release
introduce KVWriter
only one writer active
access to all operations
allows for consisten read-modify-write
must close to release
introduce AssociativeMerge operation on batch
allows efficient read-modify-write
for associative operations
used to consolidate updates to the term summary rows
saves 1 set and 1 get op per shared instance of term in field
In the index package
introduced an IndexReader
exposes a consisten snapshot of the index for searching
At top level
All searches now operate on a consisten snapshot of the index
this started initially to relocate highlighting into
a self contained package, which would then also use
the registry
however, it turned into a much larger refactor in
order to avoid cyclic imports
now facets, searchers, scorers and collectors
are also broken out into subpackages of search