redesign for better IO performance
enhanced database seek-time by avoiding write operations at distant
positions of a database file. until now, a USEDC counter was written
at the head-section of a kelondroRecords database file (which is the
basic data structure of all kelondro database files) to store the
actual number of records that are contained in the database. Now, this
value is computed from the database file size. This is either done
only once at start-time, or continuously when run in asserts enabled.
The counter is then updated only in RAM, and written at close of the
file. If the close fails, the correct number can be computed from the
file size, and if this is not equal to the stored number it is a strong
evidence that YaCY was not shut down properly.
To preserve consistency, the complete storage-routine had to be re-written.
Another change enhances read of nodes in some cases, where the data-tail
can be read together with the data-head. This saves another IO lookup during
each DB node fetch.
Includes also many small bugfixes.
IF ANYTHING GOES WRONG, ALL YOUR DATA IS LOST: PLEASE MAKE A BACK-UP
git-svn-id: https://svn.berlios.de/svnroot/repos/yacy/trunk@3375 6c8d7289-2bf4-0310-a012-ef5d649a1542
- controlled object order for all database tables
- migrated DHT position computation to correct base64-decoded values
this also closed the 'gaps' in the dht positions
git-svn-id: https://svn.berlios.de/svnroot/repos/yacy/trunk@3049 6c8d7289-2bf4-0310-a012-ef5d649a1542
Such constraints may formulate specific restrictions to web searches
This is implemented by scraping information for constraints from a web
page during parsing, and storing flags to the pages within the web index.
In this first step, only information for index pages ("index of", directory listings)
are scraped and stored in flags
- added new flag class kelondroBitfield
- added scraper method in condenser
- added bitfield structure for all scrape types (see also condenser)
- added bitfield structure for appearance locations (see RWIEntry)
- added handover protocol for remote search and index distribution
- extended kelondroColumn class to hold bitfield types
- added another search attribute on search page (index.html)
- extended search-filter to enable filtering of non-matching constraints
- set all new database types to be default
- refactoring: moved word hash generation to condenser class
git-svn-id: https://svn.berlios.de/svnroot/repos/yacy/trunk@2999 6c8d7289-2bf4-0310-a012-ef5d649a1542
- moved all url and index(RWI) entries to index package
- better naming to distinguish RWI entries and URL entries
git-svn-id: https://svn.berlios.de/svnroot/repos/yacy/trunk@2937 6c8d7289-2bf4-0310-a012-ef5d649a1542
this should reduce IO a lot, because write caches are now actived for all databases
- added new caching class that combines a read- and write-cache.
- removed old read and write cache classes
- removed superfluous RAM index (can be replaced by kelonodroRowSet)
- addoped all current classes that used the old caching methods
- more asserts, more bugfixes
git-svn-id: https://svn.berlios.de/svnroot/repos/yacy/trunk@2865 6c8d7289-2bf4-0310-a012-ef5d649a1542
- generalized object caching and added new object caching class
- added object caching wherever kelondroTree was used
- added object caching also to usage of kelondroFlex
- added object buffering (a write cache) to NURLs
- added many assert statements; fixed bugs here and there
- added missing close methods to latest added classes
git-svn-id: https://svn.berlios.de/svnroot/repos/yacy/trunk@2858 6c8d7289-2bf4-0310-a012-ef5d649a1542
* replaced kelondroTree for NURLs by kelondroFlex
* replaced kelondroTree for EURLs by kelondroFlex
take care, may be very buggy
please finish crawls before updating. crawls will be lost.
git-svn-id: https://svn.berlios.de/svnroot/repos/yacy/trunk@2452 6c8d7289-2bf4-0310-a012-ef5d649a1542
* cleaned up code
* added unit test code
* migrated ranking RCI computation to kelondroFlex and kelondroCollectionIndex
git-svn-id: https://svn.berlios.de/svnroot/repos/yacy/trunk@2414 6c8d7289-2bf4-0310-a012-ef5d649a1542
* adopted all code to use the declaration form of kelondroRow
* fixed a bug in kelondroRow which caused wrong parsing of encoding type
* the bug caused bad database behaviour in new indexCollection data structure.
because of this bug, all test databases are now already void. A new database is created
* the kelondroFlexTable and indexCollection data structures now store a declaration of the row definition
into a properties file along the database files.
git-svn-id: https://svn.berlios.de/svnroot/repos/yacy/trunk@2375 6c8d7289-2bf4-0310-a012-ef5d649a1542
* store() is now called explicitely
* more urls are written to the EURL table
* the EURL stack does not store the complete entry any more, now only the URL hash
git-svn-id: https://svn.berlios.de/svnroot/repos/yacy/trunk@2323 6c8d7289-2bf4-0310-a012-ef5d649a1542
This shall be seen as an experiment to exclude all cases where
there could be a DNS lookup during URL comparisment.
git-svn-id: https://svn.berlios.de/svnroot/repos/yacy/trunk@2290 6c8d7289-2bf4-0310-a012-ef5d649a1542
- Improve performance of plasmaURL.exists() by remembering URL-hashes that are not present
- Use a more realistic estimation of memory usage by the existsIndex cache
- Routine cleanup of the existsIndex to limit its memory usage
git-svn-id: https://svn.berlios.de/svnroot/repos/yacy/trunk@2113 6c8d7289-2bf4-0310-a012-ef5d649a1542
the kelondro database needs specific information about the order of
base64-encoded keys. Since no other package depends on base64
(only the httpd uses base64 for encryption, but does not need to encode these strings)
it is good to move base64 encoding to the new ordering classes in kelondro.
git-svn-id: https://svn.berlios.de/svnroot/repos/yacy/trunk@1284 6c8d7289-2bf4-0310-a012-ef5d649a1542
This should increase IO performance and reduce HD activity
* bugfixes for new exception-on-failure policy
* bugfixes for new IOChunks
* new Object pool for database write-buffer
git-svn-id: https://svn.berlios.de/svnroot/repos/yacy/trunk@1204 6c8d7289-2bf4-0310-a012-ef5d649a1542
(no more NULL values are returned, instead, an IOException is thrown)
- removed ugly damagedURLS implementation from plasmaCrawlLURL.java
(this inserted a static value into the Object which is not really a good style)
- re-coded damagedURLS collection in yacy.java by catching an exception and evaluating the exception message
to do:
- the urldbcleanup feature must be re-tested
git-svn-id: https://svn.berlios.de/svnroot/repos/yacy/trunk@1200 6c8d7289-2bf4-0310-a012-ef5d649a1542