This was caused by incorrect usage of the renderInto() function, which was always buggy and should never be used. This method is removed with this change.
This was caused by incorrect usage of the renderInto() function, which was always buggy and should never be used. This method is removed with this change.
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.
Modify processingiterator to be constructed via a factory, to enable re-use of its backing executor service.
This reduces thread churn in the converter sideloader style processing of regular crawl data.
Route the sizeHint from the input parquet file to SideloadProcessing, so that it can set sideloadSizeAdvice appropriately, instead of using a fixed "large" number.
This is necessary to populate the KNOWN_URL column in the domain data table, which is important as it is used in e.g. calculating how far to re-crawl the site in the future.
The URI query string is now URL encoded in the WarcProtocolReconstructor. This change ensures proper encoding of special characters as per the standard URL encoding rules and improves URL validity during the crawling process.
Updated ProcessingIterator's queue polling from one second to 50 milliseconds for improved performance. This facilitates faster document processing across more cores, reducing bottlenecks and slow single-threaded processing.
Use ProcessingIterator to fan out processing of documents across more cores, instead of doing all of it in the writer thread blocking everything else with slow single-threaded processing.
This commit adds a safety check that the URL of the document is from the correct domain.
It also adds a sizeHint() method to SerializableCrawlDataStream which *may* provide an indication if the stream is very large and benefits from sideload-style processing (which is slow).
It furthermore addresses a bug where the ProcessedDomain.write() invoked the wrong method on ConverterBatchWriter and only wrote the domain metadata, not the rest...
The processor normally retains the domain data in memory after processing to be able to do additional site-wide analysis. This works well, except there are a number of outlier websites that have an absurd number of documents that can rapidly fill up the heap of the process.
These websites now receive a simplified treatment. This is executed in the converter batch writer thread. This is slower, but the documents will not be persisted in memory.
With the new crawler modifications, the crawl data comes in a slightly different order, and a result of this is that we can optimize the converter. This is a breaking change that will be incompatible with the old style of crawl data, hence it will linger as a branch for a while.
The first step is to move stuff out of the domain processor into the document processor.
Guava's hashers are a bit allocation hungry, and a big driver of GC churn in the crawler. This switches to the modified Murmur hash function used throughout Marginalia.
Modified site info feed template to secure the description field against injected code. Also adjusted search service by extracting samples within the correct scope and including them in the returned site info. This improves the quality and security of the displayed information.
This change integrates the Feedlot RSS Bot with Marginalia's site info view to offer a preview of the latest updates.
The change introduces a new tiny feature that is a feedlot-client based on Java's HttpClient.
This is for filtering results on how many times the term appears on the domain. The intent is to be beneficial in creating e.g. a domain search feature. It's also very helpful when tracking down spammy domains.
A number of crawl jobs get stuck at about 300 documents, or just under. This seems to be because we fail to increase the crawl limit, which is based on MAX(200, 1.25 x GOOD_URLS) with a 1.5x modifier applied upon a recrawl. GOOD_URLS is based on how many documents successfully process, which is typically fairly small. Switching to KNOWN_URLS should let this grow faster.
The SQL query in the DbCrawlSpecProvider class has been updated; 'GOOD_URLS' has been replaced with 'KNOWN_URLS'. This update ensures the correct data is selected from the DOMAIN_METADATA table.
The floor is also increased to 250 from 200.
Added functionality to remove processes from listing that have not checked in for over a day. A 'removeProcessHeartbeat' function was created to delete the respective entry from the PROCESS_HEARTBEAT table in case heartbeats are absent for more than one day.
This fixes a bug where a prepared statement was created before the table it was supposed to insert into was created. This fails and does nothing.
Furthermore, added the logging that would have warned about this failure, had it been in place.
Since the sideloaders don't populate the documents list in ProcessedDomain to keep the memory footprint manageable, the code that estimates knownUrls etc. will set them to zero, which has negative effects on their ranking. This change will populate them with a bullshit value within a sane ballpark, ensuring that these domains show up in the rankings.
Make some temporary modifications to the CrawledDocument model to support both a "big string" style headers field like in the old formats, and explicit fields as in the new formats. This is a bit awkward to deal with, but it's a necessity until we migrate off the old formats entirely.
The commit also adds a few tests to this logic.
The size of the ArrayBlockingQueue in ConverterWriter.java has been reduced from 4 to 1. This change aims to reduce the memory utilization by not having fully processed domains piling up in RAM. This may cause the writer to go idle in waiting for new data, but that may be preferable to an OOM.
Initialization parameters in DomainLoaderService and DomainIdRegistry have been updated to improve performance. This is done by adding sane default sizes to the hash tables involved, reducing GC churn, but also by setting a sensible fetch size to the queries used, and not fetching irrelevant information such as the domain name.
We do both ip2location and ASN data.
The change also adds some keywords based on autonomous system information, on a somewhat experimental basis. It would be neat to be able to e.g. exclude cloud services or just e.g. cloudflare from the search results.
This variable had a very confusing name, and was dangerously easy to use in the wrong place with the result of getting something that only works as expected half the time.
Ideally this class needs an overhaul, the assumptions it makes about domain names aren't great.
This variable had a very confusing name, and was dangerously easy to use in the wrong place with the result of getting something that only works as expected half the time.
Ideally this class needs an overhaul, the assumptions it makes about domain names aren't great.
This had the knock-on effect of breaking the anchor tag loading in the processor for a lot of domains, since they'd grab domains for the wrong domain name.
In encyclopedia, add a class "mw-content-text" that the WikiSpecialization class is looking for during pruning to give the articles a more fair treatment.
Also add generator keywords based on the generator type provided, to ensure that these documents show up in appropriate filters.
Further, add a new document flag value 'Sideloaded' to be able to distinguish these entries.
This is caused by a resource contention with the query code. The proper way to fix this is to use some form of synchronization, but that will slow the code down. So we just hammer it a few times and let the GC deal with the problem if it fails. Not optimal, but fast.
The code now intercepts and deals with potential exceptions during the parsing of search parameters. This is in response to constant bad requests from bots which were cluttering the logs. A catch clause is added that suppresses these errors and redirects to the base URL.
The site info view can't blindly assume that every website supports https. To figure out which schema to use when linking to a site, execute a single-result search for site:domain.name and then grab the schema off the result.
To allow this, a count parameter is introduced to doSiteSearch() in SearchOperator.
There really is no fantastic place to put this logic, but we need to remove entries with an X-Robots-Tags header where that header indicates it doesn't want to be crawled by Marginalia.
We want to mute some of these records so that they don't produce documents, but in some cases we want a document to be produced for accounting purposes.
Added improved tests that reach for known resources on www.marginalia.nu to test the behavior when encountering bad content type and 404s.
The commit also adds some safety try-catch:es around the charset handling, as it may sometimes explode when fed incorrect data, and we do be guessing...
This commit updates CrawlingThenConvertingIntegrationTest with additional tests for invalid, redirecting, and blocked domains. Improvements have also been made to filter out irrelevant entries in ParquetSerializableCrawlDataStream.
This update includes the addition of timestamps to the parquet format for crawl data, as extracted from the Warc stream.
The parquet format stores the timestamp as a 64 bit long, seconds since unix epoch, without a logical type. This is to avoid having to do format conversions when writing and reading the data.
This parquet field populates the timestamp field in CrawledDocument.
Add an optional new field to CrawledDocument containing information about whether the domain has cookies. This was previously on the CrawledDomain object, but since the WarcFormat requires us to write a WarcInfo object at the start of a crawl rather than at the end, this information is unobtainable when creating the CrawledDomain object.
Also fix a bug in the deduplication logic in the DomainProcessor class that caused a test to break.
This information is then propagated to the parquet file as a boolean.
For documents that are copied from the reference, use whatever value we last saw. This isn't 100% deterministic and may result in false negatives, but permits websites that used cookies but have stopped to repent and have the change reflect in the search engine more quickly.
This commit includes mostly exception handling, error propagation, a few bug fixes and minor changes to log formatting. The CrawlDelayTimer, HTTP 429 responses and IOException responses are now more accurately handled.
A non-standard WarcXEntityRefused WARC record has also been introduced, essentially acting as a rejected 'response' with different semantics.
Besides these, several existing features have been refined, such as URL encoding, crawl depth incrementing and usage of Content-Length headers.
This commit further cleans up the warc->parquet conversion. It fixes issues with redirect handling in WarcRecorder, adds support information about redirects and errors due to probe failure.
It also refactors the fetch result, body extraction and content type abstractions.
This commit cleans up the warc->parquet conversion. Records with a http status other than 200 are now included.
The commit also fixes a bug where the robots.txt parser would be fed the full HTTP response (and choke), instead of the body.
The DocumentBodyExtractor code has also been cleaned up, and now offers a way of just getting the byte[] representation for later processing, as conversion to and from strings is a bit wasteful.
This is not hooked into anything yet. The change also makes modifications to the parquet-floor library to support reading and writing of byte[] arrays. This is desirable since we may in the future want to support inputs that are not text-based, and codifying the assumption that each document is a string will definitely cause us grief down the line.
This commit is in a pretty rough state. It refactors the crawler fairly significantly to offer better separation of concerns. It replaces the zstd compressed json files used to store crawl data with WARC files entirely, and the converter is modified to be able to consume this data. This works, -ish.
There appears to be some bug relating to reading robots.txt, and the X-Robots-Tag header is no longer processed either.
A problem is that the WARC files are a bit too large. It will probably be likely to introduce a new format to store the crawl data long term, something like parquet; and use WARCs for intermediate storage to enable the crawler to be restarted without needing a recrawl.
At this stage, the crawler will use the WARCs to resume a crawl if it terminates incorrectly.
This is a WIP commit, since the warc files are not fully incorporated into the work flow, they are deleted after the domain is crawled.
The commit also includes fairly invasive refactoring of the crawler classes, to accomplish better separation of concerns.
This is the same as the prefix for the IP address, but I don't think that substantially matters, the as two have such different namespaces there can be no confusion.
In this commit, GeoIP-related classes are refactored and relocated to a common library as they are shared across multiple services.
The crawler is refactored to enable the GeoIpBlocklist to use the new GeoIpDictionary as the base of its decisions.
The converter is modified ot query this data to add a geoip:-keyword to documents to permit limiting a search to the country of the hosting server.
The commit also adds due BY-SA attribution in the search engine footer for the source of the IP geolocation data.
This commit also fixes a bug in the loader where the IP field wouldn't always populate as intended, and refactors the DomainInformationService to use significantly fewer SQL queries.
The previous version used a personalized pagerank centering on a few academic domains, but this didn't work very well and most results were not very academia-centric.
This reduces the impact of restarting the search service, as the site information takes a few minutes to load during which it's not available. It also permits exposing this information via API in the future if there is interest in this.
The assistant service was also modified to do a late load of the suggestions trie, as this is a major contributor to its start-up time.
Finally, some changes were made to the client library, a new get() method was added that takes a TypeToken to allow deserialization of generics such as List<Foo>, and the scheduler was also modified to use virtual threads.
Refactored the getDocumentsStream method in EncyclopediaMarginaliaNuSideloader to use the newly extracted ProcessingIterator class that encapsulates processing a stream of results from e.g a database query in parallel and returning the computed results as an iterator.
The iterator was also improved on to be more reliable, previous versions of the logic would sometimes deadlock due to false positives in hasMore().
The commit updates EncyclopediaMarginaliaNuSideloader to include the AnchorTextKeywords in processing documents, aiding search result relevance.
It also removes old test-related functionality and a large but fairly useless test previously used to debug a specific problem, to the detriment of the overall code quality.
A race condition was found where precession actors would sometimes skip a step, because when invoking ExecutorRemoteActor.getState(), it would get the last 'OK' actor state from a previous run of the actor!
To avoid this, the trigger method was changed from returning a boolean to the message ID, negative if an error occurred, to be passed to getState to select only messages that pertain to the present or future runs.
The converter was not properly initiating the external links for each domain, causing an NPE in conversion. This needs to be loaded later since we don't know the domain we're processing until we've seen it in the crawl data.
Also made some refactorings to make finding converter bugs easier, and finding the related domain less awkward from the SerializableCrawlData interface.
The code now includes an additional function in the DomainProcessor class that checks if a domain is associated with academia. An academic domain is identified by the ".edu" TLD, or fits a specific regex pattern matching domains like *.ac.ccTld or *.edu.ccTld.
If these conditions are met, the search term "special:academia" is added to the domain.
The existing academia search filter uses personalized pagerank to select academia-adjacent domains, but it isn't working very well. The hope is that filtering on domain names will be more effective, and that it can supplant the ranking-based approach.
Partially hook in the WarcRecorder into the crawler process. So far it's not read, but should record the crawled documents.
The WarcRecorder and HttpFetcher classes were also refactored and broken apart to be easier to reason about.
This is a first step of using WARC as an intermediate flight recorder style step in the crawler, ultimately aimed at being able to resume crawls if the crawler is restarted. This component is currently not hooked into anything.
The OkHttp3 client wrapper class 'WarcRecordingFetcherClient' was implemented for web archiving. This allows for the recording of HTTP requests and responses. New classes were introduced, 'WarcDigestBuilder', 'IpInterceptingNetworkInterceptor', and 'WarcProtocolReconstructor'.
The JWarc dependency was added to the build.gradle file, and relevant unit tests were also introduced. Some HttpFetcher-adjacent structural changes were also done for better organization.
This functionality needs to be accessed by the WarcSideloader, which is in the converter. The resultant microlibrary is tiny, but I think in this case it's justifiable.
This update includes the integration of the jwarc library and implements support for Warc file sideloading, as a first trial integration with this library.
In the future this logic probably needs to move into a separate
service, as it's still quite slow to load. But this fixes response
times and DOS potential of previous version.
