WebCache

Some pages on your project's web site are accessed often and require lots of database access to generate. To keep this from bogging down your server, BOINC caches these pages. This cache is in PROJECT/html/cache/*; a one-level hashed directory hierarchy is used to deal with large-directory performance problems.

Caching configuration #config

The file html/project/cache_parameters.inc contains a number of parameters related to caching:

TEAM_PAGE_TTL:: Cache life of team pages; default 1 hour USER_PAGE_TTL:: Cache life of user pages; default 1 hour USER_HOST_TTL:: Cache life of user host list; default 1 hour USER_PROFILE_TTL:: Cache life of profiles; default 1 hour TOP_PAGES_TTL:: Cache life of user/team/host lists; default 12 hours INDEX_PAGE_TTL:: Cache life of main page; default 1 hour MAX_CACHE_USAGE:: Max cache size; default 100 MB MIN_FREE_SPACE:: Min free space on device; default 100 MB CACHE_SIZE_CHECK_FREQ:: Check cache size on every N user accesses to cached pages; default 1000

Caching and translation #caching-and-translation

BOINC uses several web-page caching systems, which support language translation in different ways.

• Pre-generated: Pages are updated from time to time, and do not support translation. The system used for building profiles is a pre-generated cache.
• Fullpage cache: This cache system simply takes the output of a page and saves it for the future. It uses the start_cache() and end_cache() functions in cache.inc. The pages may not be translation-aware (otherwise some users will see the wrong language).
• Fullpage cache with translation: You can make the language part of the cache filename. (To do this, you need to adapt the code in cache.inc). This can be inefficient because it stores a separate copy of the page for each language.
• Object cache: This stores the data used to create the page and recreates the page every time (using any language you'd like). Use get_cached_data() in cache.inc. This is perfect for pages that are accessed commonly and by people from many nationalities (currently the top-X pages support it).

If something shows up in the wrong language it's probably because a page that was previously not being translated got translation abilities but wasn't moved to the proper cache type. Also if a page-piece that is included is now translatable, all pages that make use of this piece should now either use fullpage caching with translation, or use an object cache (nicer but takes a few more lines of coding).