3 Replies Latest reply: Mar 28, 2013 1:18 AM by Billy~Verreynne RSS

    interconnect speed on dbconsole

    DB Dude
      Hi,

      We are seeing Private Interconnect Transfer Rate (MB/Sec)     betwee 0.45 MB/Sec to 0.023 MB/Sec. This we are seeing on DB Console. (DB Console -> Cluster -> Interconnects )
      can it be due to less load on system or the interconnect it self is slow?
      Is there a way to load test interconnect?

      This is 11.2.0.3 ON AIX 7.1, paired gigabit ethernet as private interconnect.

      For both nodes following gives abt 2 ms for AVG CR BLOCK RECEIVE TIME (ms)
      select b1.inst_id, b2.value "GCS CR BLOCKS RECEIVED",
      b1.value "GCS CR BLOCK RECEIVE TIME",
      ((b1.value / b2.value) * 10) "AVG CR BLOCK RECEIVE TIME (ms)"
      from gv$sysstat b1, gv$sysstat b2
      where b1.name = 'global cache cr block receive time' and
      b2.name = 'global cache cr blocks received' and b1.inst_id = b2.inst_id
      or b1.name = 'gc cr block receive time' and
      b2.name = 'gc cr blocks received' and b1.inst_id = b2.inst_id 
      /
      Also please see following
      /home/oracle> hostname
      Hostname for Node1
      /home/oracle> netstat -p udp
      udp:
              148643921 datagrams received
              0 incomplete headers
              0 bad data length fields
              0 bad checksums
              63270 dropped due to no socket
              30286 broadcast/multicast datagrams dropped due to no socket
              0 socket buffer overflows
              148550365 delivered
              146920807 datagrams output
      --------
      /home/oracle> hostname
      Hostname for Node 2
      /home/oracle> netstat -p udp
      udp:
              74069717 datagrams received
              0 incomplete headers
              0 bad data length fields
              0 bad checksums
              36390 dropped due to no socket
              4852 broadcast/multicast datagrams dropped due to no socket
              0 socket buffer overflows
              74028475 delivered
              75133092 datagrams output
      /home/oracle>
        • 1. Re: interconnect speed on dbconsole
          Levi Pereira
          You can use the tool Swingbench.

          It introduces heavy contention on a small number of tables and is designed to stress interconnects and memory.

          http://www.dominicgiles.com/swingbench.html

          Regards,
          Levi Pereira
          • 2. Re: interconnect speed on dbconsole
            JohnWatson
            The approach I would take is to ask "do you actually have a problem?" No end user has ever telephoned the help desk to say "the interconnect transfer rate is too low". If they aren't complaining, there is no problem.

            That having been said, I've just looked at the avg global cache CR receive time on three systems, and your 2ms is not brilliant but is in the range:
            0.8
            1.2
            2.6

            --
            John Watson
            Oracle Certified Master DBA
            http://skillbuilders.com
            • 3. Re: interconnect speed on dbconsole
              Billy~Verreynne
              JohnWatson wrote:

              That having been said, I've just looked at the avg global cache CR receive time on three systems, and your 2ms is not brilliant but is in the range:
              0.8
              1.2
              2.6
              Peaking 0.69ms on a new RAC, using QDR (40Gb) Infiniband and RDS. ;-)