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  1. MariaDB Server
  2. MDEV-13049

Querying INFORMATION_SCHEMA becomes slow in MariaDB 10.1

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    Details

    • Type: Bug
    • Status: Closed (View Workflow)
    • Priority: Critical
    • Resolution: Fixed
    • Affects Version/s: 10.1, 10.1.19, 10.2, 10.1.24
    • Fix Version/s: 10.1.29, 10.2.10, 10.3.3
    • Component/s: Admin statements
    • Labels:
      None
    • Environment:
    • Sprint:
      10.2.10

      Description

      Querying INFORMATION_SCHEMA repeatedly using CentOS 6 becomes slow in MariaDB 10.1 (10.1.19, 10.1.24).

      With a basic table, and simple repeated SELECT from I_S, on CentOS 6, thus far, we see a slowdown. It remains sub-second from my testing on Windows, even up to 2K iterations.

      I will provide the CREATE TABLE and test case in a private comment.

      Here are a sample of times from 10.1.19 (compared to times on MySQL 5.5 and 5.6) on CentOS 6.8:

      MariaDB 10.1.19
      real 0m16.970s
      user 0m2.804s
      sys 0m0.303s
       
      MySQL 5.6.16
      real 0m11.291s
      user 0m2.331s
      sys 0m0.280s
       
      MySQL 5.5.36
      real 0m7.246s
      user 0m2.349s
      sys 0m0.277s
      

      And here are times from Elena (10.1.24 on CentOS 6.2) using test case provided:

      real    0m4.699s
      user    0m1.641s
      sys     0m2.590s
      

      This latter one is faster than the first one, but still not sub-second.

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            Assignee:
            serg Sergei Golubchik
            Reporter:
            ccalender Chris Calender
            Votes:
            2 Vote for this issue
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              Dates

              Created:
              Updated:
              Resolved: