Uploaded image for project: 'Core Server'
  1. Core Server
  2. SERVER-15985

plan change in 2.6.5 causes query to run slower than in 2.6.4

    • Type: Icon: Bug Bug
    • Resolution: Done
    • Priority: Icon: Major - P3 Major - P3
    • None
    • Affects Version/s: 2.6.5
    • Component/s: Querying
    • None
    • ALL

      when same query and index run on 2.6.4 it is much faster then on 2.6.5 , looking at explain show second scan to not use the indexes.

      the attached js file has both query and explain results for both versions, can see millis difference . 150015 on 2.6.5 compared to 0 on 2.6.4 server.

      follow is [ObjectId()]

      query use $in and $nin .

      the affect is noticed when users is more then 110000 documents on a server with 1GB RAM.

            Assignee:
            ramon.fernandez@mongodb.com Ramon Fernandez Marina
            Reporter:
            yosi@appmahal.com yosi oren
            Votes:
            2 Vote for this issue
            Watchers:
            5 Start watching this issue

              Created:
              Updated:
              Resolved: