6.3.4. hit vs miss vs lost

an ovs-vswitchd
(...)
   DPIF-NETDEV COMMANDS
       These commands are used to expose  internal  information  (mostly  statistics)
       about  the  `dpif-netdev`  userspace datapath. If there is only one datapath
       (as is often the case, unless dpctl/ commands are used), the dp  argument  can
       be omitted.

       dpif-netdev/pmd-stats-show [dp]
              Shows  performance  statistics  for each pmd thread of the datapath dp.
              The special thread ``main'' sums up the statistics  of  every  non  pmd
              thread.   The  sum of ``emc hits'', ``masked hits'' and ``miss'' is the
              number of packets received by the datapath.  Cycles are  counted  using
              the  TSC  or  similar  facilities when available on the platform.  To
              reset these counters use dpif-netdev/pmd-stats-clear. The  duration  of
              one cycle depends on the measuring infrastructure.
(...)

Raw

man ovs-dpctl
(...)
       dump-dps
              Prints the name of each configured datapath on a separate line.

       [-s | --statistics] show [dp...]
              Prints  a summary of configured datapaths, including their datapath numbers and a list of ports connected to each datapath.  (The local port is
              identified as port 0.)  If -s or --statistics is specified, then packet and byte counters are also printed for each port.

              The datapath numbers consists of flow stats and mega flow mask stats.

              The "lookups" row displays three stats related to flow lookup triggered by processing incoming packets in the datapath. "hit"  displays  number
              of  packets  matches  existing flows. "missed" displays the number of packets not matching any existing flow and require user space processing.
              "lost" displays number of packets destined for user space process but subsequently dropped before reaching userspace.  The  sum  of  "hit"  and
              "miss" equals to the total number of packets datapath processed.
(...)

Raw

man ovs-vswitchd
(...)
       dpctl/show [-s | --statistics] [dp...]
              Prints a summary of configured datapaths, including their datapath numbers and a list of ports connected to each datapath.  (The local port is  identified  as
              port 0.)  If -s or --statistics is specified, then packet and byte counters are also printed for each port.

              The datapath numbers consists of flow stats and mega flow mask stats.

              The  "lookups"  row  displays  three  stats  related to flow lookup triggered by processing incoming packets in the datapath. "hit" displays number of packets
              matches existing flows. "missed" displays the number of packets not matching any existing flow and require user space processing.  "lost" displays  number  of
              packets  destined for user space process but subsequently dropped before reaching userspace. The sum of "hit" and "miss" equals to the total number of packets
              datapath processed.
(...)

an ovs-vswitchd
(...)
   DPIF-NETDEV COMMANDS
       These commands are used to expose  internal  information  (mostly  statistics)
       about  the  `dpif-netdev`  userspace datapath. If there is only one datapath
       (as is often the case, unless dpctl/ commands are used), the dp  argument  can
       be omitted.

       dpif-netdev/pmd-stats-show [dp]
              Shows  performance  statistics  for each pmd thread of the datapath dp.
              The special thread ``main'' sums up the statistics  of  every  non  pmd
              thread.   The  sum of ``emc hits'', ``masked hits'' and ``miss'' is the
              number of packets received by the datapath.  Cycles are  counted  using
              the  TSC  or  similar  facilities when available on the platform.  To
              reset these counters use dpif-netdev/pmd-stats-clear. The  duration  of
              one cycle depends on the measuring infrastructure.
(...)

Raw

man ovs-dpctl
(...)
       dump-dps
              Prints the name of each configured datapath on a separate line.

       [-s | --statistics] show [dp...]
              Prints  a summary of configured datapaths, including their datapath numbers and a list of ports connected to each datapath.  (The local port is
              identified as port 0.)  If -s or --statistics is specified, then packet and byte counters are also printed for each port.

              The datapath numbers consists of flow stats and mega flow mask stats.

              The "lookups" row displays three stats related to flow lookup triggered by processing incoming packets in the datapath. "hit"  displays  number
              of  packets  matches  existing flows. "missed" displays the number of packets not matching any existing flow and require user space processing.
              "lost" displays number of packets destined for user space process but subsequently dropped before reaching userspace.  The  sum  of  "hit"  and
              "miss" equals to the total number of packets datapath processed.
(...)

Raw

man ovs-vswitchd
(...)
       dpctl/show [-s | --statistics] [dp...]
              Prints a summary of configured datapaths, including their datapath numbers and a list of ports connected to each datapath.  (The local port is  identified  as
              port 0.)  If -s or --statistics is specified, then packet and byte counters are also printed for each port.

              The datapath numbers consists of flow stats and mega flow mask stats.

              The  "lookups"  row  displays  three  stats  related to flow lookup triggered by processing incoming packets in the datapath. "hit" displays number of packets
              matches existing flows. "missed" displays the number of packets not matching any existing flow and require user space processing.  "lost" displays  number  of
              packets  destined for user space process but subsequently dropped before reaching userspace. The sum of "hit" and "miss" equals to the total number of packets
              datapath processed.
(...)