The new converter logic assumes that the crawl data is ordered where the domain record comes first, and then a sequence of document records. This is true for the new parquet format, but not for the old zstd/gson format.
To make the new converter compatible with the old format, a specialized reader is introduced that scans for the domain record before running through the sequence of document records; and presenting them in the new order.
This is slower than just reading the file beginning to end, so in order to retain performance when this ordering isn't necessary, a CompatibilityLevel flag is added to CrawledDomainReader, permitting the caller to decide how compatible the data needs to be.
Down the line when all the old data is purged, this should be removed, as it amounts to technical debt.
The EC_DOMAIN_LINK MariaDB table stores links between domains. This is problematic, as both updating and querying this table is very slow in relation to how small the data is (~10 GB). This slowness is largely caused by the database enforcing ACID guarantees we don't particularly need.
This changeset replaces the EC_DOMAIN_LINK table with a file in each index node containing 32 bit integer pairs corresponding to links between two domains. This file is loaded in memory in each node, and can be queried via the Query Service.
A migration step is needed before this file is created in each node. Until that happens, the actual data is loaded from the EC_DOMAIN_LINK table, but accessed as though it was a file.
The changeset also migrates/renames the links.db file to documents.db to avoid naming confusion between the two.
Added a new constant, MAX_TEXT_LENGTH, to the SentenceExtractor class. If the length of the text input exceeds this limit, the text is truncated to fit within the limit. This modification is designed to prevent excessive resource usage for unusually long text inputs.
Added a new constant, MAX_TEXT_LENGTH, to the SentenceExtractor class. If the length of the text input exceeds this limit, the text is truncated to fit within the limit. This modification is designed to prevent excessive resource usage for unusually long text inputs.
There was as bug where if the input of ResultValuator.normalize() was negative, it was truncated to zero. This meant that "bad" results always rank the same. The penalty factor "overallPart" was moved outside of the function and was re-weighted to accomplish a better normalization.
Some of the weights were also re-adjusted based on what appears to produce better results. Needs evaluation.
This seems like it would make the wikipedia search result worse, but it drastically improves the result quality!
This is because wikipedia has a lot of articles that each talk about a lot of irrelevant concepts, and indexing the entire document means tangentially relevant results tend to displace the most relevant results.
There was as bug where if the input of ResultValuator.normalize() was negative, it was truncated to zero. This meant that "bad" results always rank the same. The penalty factor "overallPart" was moved outside of the function and was re-weighted to accomplish a better normalization.
Some of the weights were also re-adjusted based on what appears to produce better results. Needs evaluation.
This seems like it would make the wikipedia search result worse, but it drastically improves the result quality!
This is because wikipedia has a lot of articles that each talk about a lot of irrelevant concepts, and indexing the entire document means tangentially relevant results tend to displace the most relevant results.
