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  1. Moodle
  2. MDL-69886

Tags block should cache the tags cloud SQL results

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    • Affected Branches:
      MOODLE_39_STABLE

      Description

      We are experiencing performance issues with the Tags block on moodle.org where we use a single tags collection (users' interests) with a few tens of thousands tags and tag instances.

      The block calls core_tag_collection::get_tag_cloud() on every single page load and generating the tags cloud take a significant time (we suspect due to sorting involved).

      This represents a potential surface for a DoS attack on bigger sites with many tags using the block.

      It is apparent that the block could cache the results for a while instead of populating the same aggregated cloud over and over again.

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            Assignee:
            Unassigned Unassigned
            Reporter:
            mudrd8mz David Mudrák (@mudrd8mz)
            Participants:
            Component watchers:
            Adrian Greeve, Jake Dallimore, Mathew May, Mihail Geshoski, Peter Dias, Sujith Haridasan, Matteo Scaramuccia, Andrew Nicols, Dongsheng Cai, Huong Nguyen, Jun Pataleta, Michael Hawkins, Shamim Rezaie, Simey Lameze, Amaia Anabitarte, Carlos Escobedo, Ferran Recio, Ilya Tregubov, Sara Arjona (@sarjona)
            Votes:
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            2 Start watching this issue

              Dates

              Created:
              Updated: