2 Commits

Author	SHA1	Message	Date
Jan Scheurich	79f368756c	dpif-netdev: Detailed performance stats for PMDs ... This patch instruments the dpif-netdev datapath to record detailed statistics of what is happening in every iteration of a PMD thread. The collection of detailed statistics can be controlled by a new Open_vSwitch configuration parameter "other_config:pmd-perf-metrics". By default it is disabled. The run-time overhead, when enabled, is in the order of 1%. The covered metrics per iteration are: - cycles - packets - (rx) batches - packets/batch - max. vhostuser qlen - upcalls - cycles spent in upcalls This raw recorded data is used threefold: 1. In histograms for each of the following metrics: - cycles/iteration (log.) - packets/iteration (log.) - cycles/packet - packets/batch - max. vhostuser qlen (log.) - upcalls - cycles/upcall (log) The histograms bins are divided linear or logarithmic. 2. A cyclic history of the above statistics for 999 iterations 3. A cyclic history of the cummulative/average values per millisecond wall clock for the last 1000 milliseconds: - number of iterations - avg. cycles/iteration - packets (Kpps) - avg. packets/batch - avg. max vhost qlen - upcalls - avg. cycles/upcall The gathered performance metrics can be printed at any time with the new CLI command ovs-appctl dpif-netdev/pmd-perf-show [-nh] [-it iter_len] [-ms ms_len] [-pmd core] [dp] The options are -nh: Suppress the histograms -it iter_len: Display the last iter_len iteration stats -ms ms_len: Display the last ms_len millisecond stats -pmd core: Display only the specified PMD The performance statistics are reset with the existing dpif-netdev/pmd-stats-clear command. The output always contains the following global PMD statistics, similar to the pmd-stats-show command: Time: 15:24:55.270 Measurement duration: 1.008 s pmd thread numa_id 0 core_id 1: Cycles: 2419034712 (2.40 GHz) Iterations: 572817 (1.76 us/it) - idle: 486808 (15.9 % cycles) - busy: 86009 (84.1 % cycles) Rx packets: 2399607 (2381 Kpps, 848 cycles/pkt) Datapath passes: 3599415 (1.50 passes/pkt) - EMC hits: 336472 ( 9.3 %) - Megaflow hits: 3262943 (90.7 %, 1.00 subtbl lookups/hit) - Upcalls: 0 ( 0.0 %, 0.0 us/upcall) - Lost upcalls: 0 ( 0.0 %) Tx packets: 2399607 (2381 Kpps) Tx batches: 171400 (14.00 pkts/batch) Signed-off-by: Jan Scheurich <jan.scheurich@ericsson.com> Acked-by: Billy O'Mahony <billy.o.mahony@intel.com> Signed-off-by: Ian Stokes <ian.stokes@intel.com>	2018-05-11 08:08:24 +01:00
Jan Scheurich	82a48ead4e	dpif-netdev: Refactor PMD performance into dpif-netdev-perf ... Add module dpif-netdev-perf to host all PMD performance-related data structures and functions in dpif-netdev. Refactor the PMD stats handling in dpif-netdev and delegate whatever possible into the new module, using clean interfaces to shield dpif-netdev from the implementation details. Accordingly, the all PMD statistics members are moved from the main struct dp_netdev_pmd_thread into a dedicated member of type struct pmd_perf_stats. Include Darrel's prior refactoring of PMD stats contained in [PATCH v5,2/3] dpif-netdev: Refactor some pmd stats: 1. The cycles per packet counts are now based on packets received rather than packet passes through the datapath. 2. Packet counters are now kept for packets received and packets recirculated. These are kept as separate counters for maintainability reasons. The cost of incrementing these counters is negligible. These new counters are also displayed to the user. 3. A display statistic is added for the average number of datapath passes per packet. This should be useful for user debugging and understanding of packet processing. 4. The user visible 'miss' counter is used for successful upcalls, rather than the sum of sucessful and unsuccessful upcalls. Hence, this becomes what user historically understands by OVS 'miss upcall'. The user display is annotated to make this clear as well. 5. The user visible 'lost' counter remains as failed upcalls, but is annotated to make it clear what the meaning is. 6. The enum pmd_stat_type is annotated to make the usage of the stats counters clear. 7. The subtable lookup stats is renamed to make it clear that it relates to masked lookups. 8. The PMD stats test is updated to handle the new user stats of packets received, packets recirculated and average number of datapath passes per packet. On top of that introduce a "-pmd <core>" option to the PMD info commands to filter the output for a single PMD. Made the pmd-stats-show output a bit more readable by adding a blank between colon and value. Signed-off-by: Jan Scheurich <jan.scheurich@ericsson.com> Co-authored-by: Darrell Ball <dlu998@gmail.com> Signed-off-by: Darrell Ball <dlu998@gmail.com> Acked-by: Ilya Maximets <i.maximets@samsung.com> Acked-by: Billy O'Mahony <billy.o.mahony@intel.com> Signed-off: Ian Stokes <ian.stokes@intel.com>	2018-01-17 18:11:28 +00:00