Uploaded image for project: 'Core Server'
  1. Core Server
  2. SERVER-31694

17% throughput regression in insert workload

    • Type: Icon: Bug Bug
    • Resolution: Incomplete
    • Priority: Icon: Major - P3 Major - P3
    • None
    • Affects Version/s: 3.6.0
    • Component/s: Storage, Write Ops
    • None
    • Replication
    • Storage 2017-11-13, Storage 2017-12-04, Storage 2018-01-29, Repl 2018-02-26, Repl 2018-03-12, Repl 2018-03-26
    • 0

      Simple insert workload:

          res = benchRun({
              ops: [
                  {op: "insert", doc: {},  ns: "test.c"},
              ],
              seconds: 45,
              parallel: 15
          })
          printjson(res)
      

      standalone shows ~11% throughput reduction

      3.4.9:     "totalOps/s" : 312257.31243007537,
      3.6.0-rc0  "totalOps/s" : 277214.2306740861,
      

      1-node replica set shows ~50% throughput reduction

      3.4.9:     "totalOps/s" : 181808.21357151057,
      3.6.0-rc0  "totalOps/s" : 91202.31599375796,
      

      Metrics for the 1-node replica set case suggest issue may be related to large number of write-lock calls, about 3 per insert:

        1. run2.png
          run2.png
          127 kB
        2. pmp.out.3513
          17 kB
        3. pmp.out.359
          8 kB
        4. ensure-session.patch
          2 kB
        5. pmp.patch.sesscache
          12 kB

            Assignee:
            backlog-server-repl [DO NOT USE] Backlog - Replication Team
            Reporter:
            bruce.lucas@mongodb.com Bruce Lucas (Inactive)
            Votes:
            3 Vote for this issue
            Watchers:
            45 Start watching this issue

              Created:
              Updated:
              Resolved: