attribute in the <a> tag for each crawl. This introduces a lot of
changes because it extends the usage of the AnchorURL Object type which
now also has a different toString method that the underlying
DigestURL.toString. It is therefore not advised to use .toString at all
for urls, just just toNormalform(false) instead.
- Web servers may now deliver YaCy-specific http header field with a
title and keywords. The new http header fields are:
X-YaCy-Media-Title - to be used for media (image, audio, video) titles
X-YaCy-Media-Keywords - to be used for media (image, audio, video)
keywords
- both fields are written to document fields title and keywords and are
searched also during image search.
- to make the usage of arbitrary http header fields (including this new
fields) possible in the /api/push_p.json servlet, a new POST argument is
also introduced to push http header fields. The new POST attribute is
named "responseHeader-X" (where X is the counter). It is allowed to use
this attribute as multi-attribute several times, each can be filled with
a http header line.
- see /api/push_p.html for examples
- unique-postprocessing was destroying results from other
postprocessings; removed cross-updates as they had been not necessary
- unique-postprocessing did not restrict on same protocol
- inefficient concurrent update cache was redesigned completely
- increased limits for concurrent blocking queues to prevent early
time-out
This organizes all urls to be loaded in separate queues for each host.
Each host separates the crawl depth into it's own queue. The primary
rule for urls taken from any queue is, that the crawl depth is minimal.
This produces a crawl depth which is identical to the clickdepth.
Furthermorem the crawl is able to create a much better balancing over
all hosts which is fair to all hosts that are in the queue.
This process will create a very large number of files for wide crawls in
the QUEUES folder: for each host a directory, for each crawl depth a
file inside the directory. A crawl with maxdepth = 4 will be able to
create 10.000s of files. To be able to use that many file readers, it
was necessary to implement a new index data structure which opens the
file only if an access is wanted (OnDemandOpenFileIndex). The usage of
such on-demand file reader shall prevent that the number of file
pointers is over the system limit, which is usually about 10.000 open
files. Some parts of YaCy had to be adopted to handle the crawl depth
number correctly. The logging and the IndexCreateQueues servlet had to
be adopted to show the crawl queues differently, because the host name
is attached to the port on the host to differentiate between http,
https, and ftp services.
stack on html tag objects, not using a recursive parse-again method
which may cause bad performance and huge memory allocation. The new
method also produced better parsed image objects with exact anchor text
references.
- added order option to solr queries to be able to retrieve document
lists in specific order, here: link length
- added HyperlinkEdge class which manages the link structure
- integrated the HyperlinkEdge class into clickdepth computation
- extended the linkstructure.json servlet to show also the clickdepth
and other statistic information
a document. This is the upper limit for the clickdepth_i value which may
be shorter in case that the crawler did not take the shortest path to
the document.
instead of TreeMaps)
- enhanced memory footprint of database indexes (by introduction of
optimize calls)
- optimize calls shrink the amount of used memory for index sets if they
are not changed afterwards any more
different from normal requests. This happens if the remote solr is
actually a solrCloud; in such cases the luke request returns only the
result of the single solr peer, not the whole cloud.
also done: some refactoring.
a dublin core record inside of surrogate input files may now contain
tokens within the namespace 'md' (short for: metadata). The token names
must be valid withing the namespace of the solr field names. All
md-tokens inside of surrogate files then overwrite values within solr
documents before they are written to the solr index. This makes it
possible to assign collection names to each surrogate entry and also
ranking information can be added. Please see the example file.
work around the unfolding process in Solr's BinaryResponseWriter.
This was a huge performance bottleneck in the embedded solr connector
and the problem is actually on Solr side, but we have now a workaround.
- This made it possible to abstract a high-performance index access
method which is implemented as method getDocumentListByParams. That
method is also implemented in the SolrServerConnector and provides a
very efficient access to a solr index if the index is embedded.
- a popular use of the document list retrieval is a result count which
can now also make use of the new method, via getDocumentCountByParams.
- enhanced the Error cache which now does not store error documents
within the ram cache if the document is also written to solr. When
documents are retrieved from the cache, they are partly read from the
ram cache and if not existent there, from the Solr index.
the embedded Solr (the default). This was obtained by cirumventing solrj
search encapsulation and the implementation of direct index access
methods to Solr.
The effect will not only be seen during search, but this has also a
strong effect on suggestions (much more) and less CPU power usage during
index distribution (which needs many search requests)
This shall fulfill the following requirement:
If a document A links to B and B contains a 'canonical C', then the
citation rank computation shall consider that A links to C and B does
not link to C.
To do so, we first must collect all canonical links, find all references
to them, get the anchor list of the documents and patch the citation
reference of these links.
webgraph index which is temporary filled with the crawl profile key.
This is used to select a set of documents for post-processing as soon as
a crawl is finished. Now the postprocessing for a specific crawl is
started when that specific crawl is finished and not at the end of all
post-processing steps.
there for deletion), this fixes a problem for the deletion of old
documents for new crawl starts
- added clickdepth and citation computation for fail documents
- replaced load failure logging by information which is stored in Solr
- fixed a bug with crawling of feeds: added must-match pattern
application to feed urls to filter out such urls which shall not be in a
wanted domain
- delegatedURLs, which also used ZURLs are now temporary objects in
memory
for anchor attributes.
- this caused that large portions of the parser code had to be adopted
as well
- added a counter target_order_i for anchor links in webgraph
computation
all unique links! This made it necessary, that a large portion of the
parser and link processing classes must be adopted to carry a different
type of link collection which carry a property attribute which are
attached to web anchors.
- introduction of a new URL class, AnchorURL
- the other url classes, DigestURI and MultiProtocolURI had been renamed
and refactored to fit into a new document package schema, document.id
- cleanup of net.yacy.cora.document package and refactoring
html meta fields to get a correct (or: better) date timestamp. The
http:last-modified mostly does not work because it is set to the current
date from most CMS.
fuzzy_signature_copycount_i, which count the number of copies of
non-unique documents and assigns this to each document. Thus, each
document there is a number assigned which shows how many copies of this
document exists.
These fields are disabled by default.
regular expression on th url: the collection attribut for a crawl start
may be now either a token or a list of tokens, seperated by ',' where a
token is either a string or a pair <string,pattern> where the string is
separated to the pattern with a ':' and the string is assigned to the
document as collection only if the pattern matches with the url.
E 2013/07/26 20:29:29 BUSYTHREAD Runtime Error in
serverInstantThread.job, thread
'net.yacy.search.Switchboard.cleanupJob': null; target exception: null
java.lang.NullPointerException
at
net.yacy.search.schema.CollectionConfiguration.convergenceStep(CollectionConfiguration.java:1116)
at
net.yacy.search.schema.CollectionConfiguration.postprocessing(CollectionConfiguration.java:897)
at net.yacy.search.Switchboard.cleanupJob(Switchboard.java:2296)
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at
sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:57)
at
sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
at java.lang.reflect.Method.invoke(Method.java:606)
at
net.yacy.kelondro.workflow.InstantBusyThread.job(InstantBusyThread.java:107)
at
net.yacy.kelondro.workflow.AbstractBusyThread.run(AbstractBusyThread.java:165)
Conflicts:
source/net/yacy/search/schema/CollectionConfiguration.java
of the lazy instantiation rule this value was not actually written, but
if lazy instantiation is switched on, then this causes that all crawl
starts delete all crawl-start-hosts completely because this looks for
filled error reasons.
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
without the file extension. This part of the file path is removed from
the multi-field url_paths_sxt, which has now not the file name as last
part of the path list.
The same applies to the new fields source_file_name_s and
target_file_name_s in the webgraph schema.
references_internal_url_sxt because they had been shown to be
superfluous. The citation of referrer in the host browser is possible
without them. Therefore now the host browser does not only show
internal, but also external referrer to each link.
While the values for the reference evaluation are computed, also a
backlink-structure can be discovered and written to the index as well.
The host browser has been extended to show such backlinks to each
presented links. The host browser therefore can now show an information
where an document is linked. The new citation reference is computed as
likelyhood for a random click path with recursive usage of previously
computed likelyhood. This process is repeated until the likelyhood
converges to a specific number. This number is then normalized to a
ranking value CRn, 0<=CRn<=1. The value CRn can therefore be used to
rank popularity within intra-domain link structures.
holds the number of documents for the host where the document is hosted.
This is necessary for ranking and the norming of references per local
host in the ranking computation.
references_external_i and references_exthosts_i. These can be used to
count and evaluate the number of external links to every web page. An
experimental ranking function can be i.e.:
div(add(references_internal_i,product(references_external_i,references_exthosts_i)),add(clickdepth_i,1))
- 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
Conflicts:
htroot/IndexFederated_p.html
source/net/yacy/cora/federate/solr/YaCySchema.java
source/net/yacy/peers/Protocol.java
source/net/yacy/search/Switchboard.java
source/net/yacy/search/index/Segment.java
also moved portalsearch-dev to yacy-portalsearch to be able to fix
problems with new attachment to solr of the search widget
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
Michael Peter Christen