as soon as the number of requests is > 50, there is a forced delay
of (10 * (requests - 50)) milliseconds. That means that once the number
of DNS requests reach 150, there is a one second delay to each request.
This shall prevent that a remote DNS is flooded with request and
possibly gets damaged.
This is also a fix/enhancement for
https://github.com/yacy/yacy_search_server/issues/513
instead of loading the solr document, an index only for the last loading
time was created. This prevents that solr has to fetch from its index
while the index is created. Excessive re-loading of documents while
indexing has shown to produce deadlocks, so this should now be
prevented.
a main problem when crawling is long waiting time cuased by crawl-delay
values from robots.txt entries. that attribute is not supported by
google and interpreted by yandex and bing in different ways. In large
crawls there is always one host which blocks the whole crawl with
extreme large values. YaCy now still obeys crawl-delay but limits them
to 10 seconds.
Additionally the blocking logic when loading new robots.txt was analyzed
and a deadlock was removed. Furthermore the construction of new queue
lists was redesigned and it was ensured that always a large list of
different hosts for host-balancing is provided for the loader.
- replace new guava 30 with older 25 because that is the correct
dependency for solr 8.8.1. The newer one did actually not work!
- index will be crated in a DATA/INDEX/freeworld/SEGMENTS/solr_8_8_1
subfolder. The older solr_6_6 index is not touched but also not
migrated. The index starts with fresh (empty) content.
- Older indexes must be migrated by hand (export/import) so far until a
better solution is found.
- Large schema adoptions for lucene 8.8.1
Michael Peter Christen