jdk-based logger tend to block
at java.util.logging.Logger.log(Logger.java:476) in concurrent
environments. This makes logging a main performance issue. To overcome
this problem, this is a add-on to jdk logging to put log entries on a
concurrent message queue and log the messages one by one using a
separate process.
- FTPClient uses the concurrent logging instead of the log4j logger
used to select between different collections as defined during a crawl
start with the 'collection' attribute. This actually implements the
ability to prepare search tenants which restrict their search results to
a specific collection. The main use for this is to provide tenants to
the yaml4 interface (at this time).
search interfaces if no other ranking attributes are given
- using the YaCy ranking in the GSA interface only if there was not
given a GSA-style sort attribute
- to avoid confusion about correct ranking attributes, only the default
'0'-ranking profile is used and not scenario-adopted (site, date)
because that should be configurable in the web interface before it is
used actually for ranking.
- an existing ranking servlet for solr was extended. It is now possible
to set boost values for fields, boost functions and boost queries.
- The ranking can have different instances, but currently only the first
one is used
- added an abstraction layer for fields which can be used for search and
those fields can be edited in the solr ranking configruation
- the ranking value from solr within the field score is used to combine
remote search requests, which all are created using the same locally
defined boost values
- reduced the number of fields which are used for search (makes it
faster)
- replaced some text fields by string fields (makes indexing faster)
- removed classes which had no use
- made a large number of experiments for a better ranking and created a
temporary setting which prefers hits inside titles
- adjusted also the RWI-based ranking computation to 'prefer title'
- made special cases like for portal search where no post-processing and
post-ranking is wanted: this keeps the original ranking order as done by
Solr
- fixed many bugs with old settings for ranking
- removed 'worker' processes
- no internal time-out behaviour: methods either are successful or
return null
- waiting is only done on top-level
- removed snippet-production; this is replaced by solr snippets
- removed statistics based on solr size queries (they had been VERY
long); the statistics (like suggestions or tag cloud) are now again
based on the old but very fast RWI index. In portal or intranet mode the
RWI index is usually switched off; if you like to have statistics again
then you must switch on the rwis again in this mode.
- fixed many bugs regarding correct page counter
The default schema uses only some of them and the resting search index
has now the following properties:
- webgraph size will have about 40 times as much entries as default
index
- the complete index size will increase and may be about the double size
of current amount
As testing showed, not much indexing performance is lost. The default
index will be smaller (moved fields out of it); thus searching
can be faster.
The new index will cause that some old parts in YaCy can be removed,
i.e. specialized webgraph data and the noload crawler. The new index
will make it possible to:
- search within link texts of linked but not indexed documents (about 20
times of document index in size!!)
- get a very detailed link graph
- enhance ranking using a complete link graph
To get the full access to the new index, the API to solr has now two
access points: one with attribute core=collection1 for the default
search index and core=webgraph to the new webgraph search index. This is
also avaiable for p2p operation but client access is not yet
implemented.
structure, but is not filled yet. To have the opportunity of a second
core, multi-core functionality had to be implemented to the
deep-embedded solr:
- migrated the solr_40 directory content to a subdirectory
'collection1'; the previously used default core is now called
collection1
- added solr_40/webgraph subdirectory as second core
- added a servlet configuration for the second core 'webgraph' in
/IndexSchema_p.html
- added instance handling as addition to solr connections: all solr
connectors are now instances of an solr 'instance' object; this required
a complete re-design of the solr embedding
- migrated also caching and sharding ontop of new instance handling
- migrated the search apis to handle now the access to a specific core,
the default core named 'collection1'
- migrated the remote solr search interface to access shards of cores;
for the yacy remote search the default core is now called 'solr'; using
the peer address as solr address
- migrated the solr backup and restore process: old backups cannot be
used after this migration!
- redesign of solr instance handling in all methods which access the
instances: they cannot hold copies of these instances any more; the must
retrieve the actuall connection object every time they want to write to
it (this solves also some bugs when switching the index/network)
- added another schema 'solr.webgraph.schema', the old solr.keys.list is
replaced by solr.collection.schema
multiple solr cores instead of just one. Therefore it is now necessary
to distuingish between solr server connections (called an 'Instance')
and a connection to a single solr core. One Instance may now have
multiple connector classes assigned to it, each connecting to a single
core.
To support multiple cores it is also necessary to distinguish between
the connection configuration and the configuration of the index schema.
We will have multiple schema configurations in the future, each for
every solr core. This caused that the IndexFederated servlet had to be
split into two parts, the new Servlet for the Schema editor is now in
the IndexSchema Servlet.
Solr search interface in such way that it is possible to use this
interface for the yacyinteractive search. This search interface is now
much faster using the Solr search directly. For the Solr interface it
was necessary to create a translation from the YaCy search modifiers to
the Solr facet selection. This was added in such a way that it becomes
generic for the normal YaCy search and as a on-top evaluation for Solr
queries.
- when using a site operator search for a domain where the domain has a
www prefix, also the domain without the www is enclosed
- when using a site operator search for a domain where the domain has no
www prefix, also the domain with the www in enclosed
- in the host navigator, all domains with and without a www prefix are
accumulated. That means that the host navigator does never show a host
with a www prefix.
This should prevent usage mistakes of the site operator.
forum at
http://forum.yacy-websuche.de/viewtopic.php?f=18&t=4572#p27410
The feature was not called 'haslink' but called 'inlink' to have a
analogous naming like 'inurl'. This causes now that you can search for
words in links of the document, like:
* inlink:yacy
searches all documents which link to pages which have an 'yacy' in the
url.
that enables viewing of images for intranet SMB servers.
- added a filter search for protocol, tld and ext again; otherwise p2p
search produces a lot of rubbish
proper/known
- automatically show the protocol navigation if there is more than http
and https
- automatically show the extension navigation if there is some media
content
introduce a copy-field for the author field to be copied to a string
field. This field is then used to generate facets. Without this field,
the facet would consist only of the words of the author names, not of
the full author string.
INCOMING links to the corresponding web page. This information is taken
from the reverse link index (a 'little sister' of the RWI index).
- this field can be of use to enhance the ranking because a web page
with more incoming links can be more more important than others. But
this is not true for typical link pages like menues. Therefore the
number of outgoing links is needed.
- added a new solr attribute 'bf' to solr queries which is a boost
function extension. this field can contain a formula which comuptes the
boost according to given field values. After some experiments the
following forumla is now default:
div(add(1,references_i),pow(add(1,inboundlinkscount_i),1.6))^0.4
This takes the number of references and the inbound links. Further
experiments are needed to enhance that forumula.
This uses an enhanced version of the Nutch/Solr TextProfileSignatue.
As a result, a signature of the document is written to the solr search
index. Additionally for each time when a signature is written, it is
checked if the singature exists already in the index. If the signature
does not exist, the document is marked as unique. The unique attribute
can now be used to sort document lists and bring duplicates to the end
of a result list.
To enable this, a large portion of the search api to Solr had to be
changed. This affected mainly caching of 'exists' searches to enhance
the check for existing signatures and do this without actually doing a
solr query.
Because here the first time a long number is used as value in the Solr
store, also the value naming in the YaCySchema had to be adopted and
normalized. This caused that many files had to be changed.
need regular expressions as search attributes. They had now been removed
from the advanced search page while they are still created internally.
The filter is then expressed against solr as regular expression filter
query. If the expression points out a selection of an specific protocol,
host or filetype this is then translated into a facetted query.
added solr highlighting / YaCy snippets to YaCy search results
- facets are now much more complete
- facets are computed and searched much faster
- snippet computation is done by solr if solr knows the snippet
Michael Peter Christen