Magento2 DevDocs available here
Configuration
Magento collects configuration from all modules, merges it, and saves the merged result to the cache. This cache also contains store-specific settings stored in the file system and database. Clean or flush this cache type after modifying configuration files.
Magento 2 devdocs
Source: Most xml config files located in etc/ directory; di.xml, config.xml, events.xml, extension_attributes.xml, product_types.xml, sections.xml, search_request.xml, sales.xml, payment.xml etc…
See \Magento\Framework\App\ObjectManager\ConfigLoader::load
\Magento\Framework\Config\Reader\Filesystem::__construct + config reader as \Magento\Framework\ObjectManager\Config\Reader\Dom::__construct, \Magento\Framework\Event\Config\Reader::__construct
Search pattern \$fileName = ‘(.*).xml’,\ to find them
Also see Configuration values loading order
Layouts
Compiled page layouts (that is, the layout components from all components). Clean or flush this cache type after modifying layout files.
Magento 2 devdocs
Source: xml files in layout/, page_layout/ directories and xml layout directives stored for each cms pages in admin (‘cms_page’ table in database)
See \Magento\Framework\View\Model\Layout\Merge::load
Blocks HTML output
HTML page fragments per block. Clean or flush this cache type after modifying the view layer.
Magento 2 devdocs
Source: *.phtml files
See \Magento\Framework\View\Element\AbstractBlock::toHtml
Collections Data
Results of database queries. If necessary, Magento cleans up this cache automatically, but third-party developers can put any data in any segment of the cache. Clean or flush this cache type if your custom module uses logic that results in cache entries that Magento cannot clean.
Magento 2 devdocs
Source: Collections queries
See \Magento\Framework\Data\Collection\Db\FetchStrategy\Cache::fetchAll
DDL
Database schema. If necessary, Magento cleans up this cache automatically, but third-party developers can put any data in any segment of the cache. Clean or flush this cache type after you make custom changes to the database schema. (In other words, updates that Magento does not make itself.) One way to update the database schema automatically is using the
Magento 2 devdocsmagento setup:db-schema:upgrade
command.
Source: db_schema.xml
Compiled config
Compilation configuration
Magento 2 devdocs
Source: Interceptors files generated in generated/ dir
Entity attribute value (EAV)
Metadata related to EAV attributes (for example, store labels, links to related PHP code, attribute rendering, search settings, and so on). You should not typically need to clean or flush this cache type.
Magento 2 devdocs
Source: eav tables
Page Cache
Generated HTML pages. If necessary, Magento cleans up this cache automatically, but third-party developers can put any data in any segment of the cache. Clean or flush this cache type after modifying code level that affects HTML output. It is recommended to keep this cache enabled because caching HTML improves performance significantly.
Magento 2 devdocs
Source: Whole rendered page (HTML)
See \Magento\PageCache\Model\App\FrontController\BuiltinPlugin::aroundDispatch
Reflection
Removes a dependency between the Webapi module and the Customer module.
Magento 2 devdocs
Source: Interfaces, not only for Customer module. Also used for Checkout, Quote, Tax and others
See \Magento\Framework\Reflection\MethodsMap::getMethodsMap
Integrations Configuration
Compiled integrations. Clean or flush this cache after changing or adding integrations.
Magento 2 devdocs
Source: integration.xml, integration/config.xml
Integrations API Configuration
Compiled integration APIs configuration of the Store’s Integrations.
Magento 2 devdocs
Source: integration/api.xml
Web Services Configuration
Caching the Web API Structure.
Magento 2 devdocs
Source: webapi.xml, webapi_async.xml
Translations
After merging translations from all modules, the merger cache will be cleaned.
Magento 2 devdocs
Source: xx_YY.csv from modules, themes, language packs and translations stored in ‘translation’ table for the current locale
See \Magento\Framework\Translate::loadData
Also see Translations loading order
Customer Notification
Temporary notifications that appear in the user interface.
Magento 2 devdocs
Source: \Magento\Customer\Model\Customer\NotificationStorage
See \Magento\Customer\Model\Plugin\CustomerNotification::beforeDispatch as example
January 9, 2020 at 8:49 AM
Thanks for sharing your knowledge !!!!