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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, Matteo Scaramuccia, Andrew Nicols, Jun Pataleta, Michael Hawkins, Shamim Rezaie, Simey Lameze, Amaia Anabitarte, Carlos Escobedo, Ferran Recio, Sara Arjona (@sarjona)
            Votes:
            2 Vote for this issue
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            2 Start watching this issue

              Dates

              Created:
              Updated: