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.scheur...@ericsson.com> --- NEWS | 3 + lib/automake.mk | 1 + lib/dpif-netdev-perf.c | 350 +++++++++++++++++++++++++++++++++++++++++++- lib/dpif-netdev-perf.h | 258 ++++++++++++++++++++++++++++++-- lib/dpif-netdev-unixctl.man | 157 ++++++++++++++++++++ lib/dpif-netdev.c | 182 +++++++++++++++++++++-- manpages.mk | 2 + vswitchd/ovs-vswitchd.8.in | 27 +--- vswitchd/vswitch.xml | 12 ++ 9 files changed, 939 insertions(+), 53 deletions(-) create mode 100644 lib/dpif-netdev-unixctl.man diff --git a/NEWS b/NEWS index d7d585b..587b036 100644 --- a/NEWS +++ b/NEWS @@ -56,6 +56,9 @@ v2.9.0 - xx xxx xxxx * Add rxq utilization of pmd to appctl 'dpif-netdev/pmd-rxq-show'. - Userspace datapath: * Output packet batching support. + * Commands ovs-appctl dpif-netdev/pmd-*-show can now work on a single PMD + * Detailed PMD performance metrics available with new command + ovs-appctl dpif-netdev/pmd-perf-show - vswitchd: * Datapath IDs may now be specified as 0x1 (etc.) instead of 16 digits. * Configuring a controller, or unconfiguring all controllers, now deletes diff --git a/lib/automake.mk b/lib/automake.mk index 159319f..54375ea 100644 --- a/lib/automake.mk +++ b/lib/automake.mk @@ -468,6 +468,7 @@ MAN_FRAGMENTS += \ lib/dpctl.man \ lib/memory-unixctl.man \ lib/netdev-dpdk-unixctl.man \ + lib/dpif-netdev-unixctl.man \ lib/ofp-version.man \ lib/ovs.tmac \ lib/service.man \ diff --git a/lib/dpif-netdev-perf.c b/lib/dpif-netdev-perf.c index f06991a..43f537e 100644 --- a/lib/dpif-netdev-perf.c +++ b/lib/dpif-netdev-perf.c @@ -15,18 +15,324 @@ */ #include <config.h> +#include <stdint.h> +#include "dpif-netdev-perf.h" #include "openvswitch/dynamic-string.h" #include "openvswitch/vlog.h" -#include "dpif-netdev-perf.h" +#include "ovs-thread.h" #include "timeval.h" VLOG_DEFINE_THIS_MODULE(pmd_perf); +#ifdef DPDK_NETDEV +static uint64_t +get_tsc_hz(void) +{ + return rte_get_tsc_hz(); +} +#else +/* This function is only invoked from PMD threads which depend on DPDK. + * A dummy function is sufficient when building without DPDK_NETDEV. */ +static uint64_t +get_tsc_hz(void) +{ + return 1; +} +#endif + +/* Histogram functions. */ + +static void +histogram_walls_set_lin(struct histogram *hist, uint32_t min, uint32_t max) +{ + int i; + + ovs_assert(min < max); + for (i = 0; i < NUM_BINS-1; i++) { + hist->wall[i] = min + (i * (max - min)) / (NUM_BINS - 2); + } + hist->wall[NUM_BINS-1] = UINT32_MAX; +} + +static void +histogram_walls_set_log(struct histogram *hist, uint32_t min, uint32_t max) +{ + int i, start, bins, wall; + double log_min, log_max; + + ovs_assert(min < max); + if (min > 0) { + log_min = log(min); + log_max = log(max); + start = 0; + bins = NUM_BINS - 1; + } else { + hist->wall[0] = 0; + log_min = log(1); + log_max = log(max); + start = 1; + bins = NUM_BINS - 2; + } + wall = start; + for (i = 0; i < bins; i++) { + /* Make sure each wall is monotonically increasing. */ + wall = MAX(wall, exp(log_min + (i * (log_max - log_min)) / (bins-1))); + hist->wall[start + i] = wall++; + } + if (hist->wall[NUM_BINS-2] < max) { + hist->wall[NUM_BINS-2] = max; + } + hist->wall[NUM_BINS-1] = UINT32_MAX; +} + +uint64_t +histogram_samples(const struct histogram *hist) +{ + uint64_t samples = 0; + + for (int i = 0; i < NUM_BINS; i++) { + samples += hist->bin[i]; + } + return samples; +} + +static void +histogram_clear(struct histogram *hist) +{ + int i; + + for (i = 0; i < NUM_BINS; i++) { + hist->bin[i] = 0; + } +} + +static void +history_init(struct history *h) +{ + memset(h, 0, sizeof(*h)); +} + void pmd_perf_stats_init(struct pmd_perf_stats *s) { - memset(s, 0 , sizeof(*s)); + memset(s, 0, sizeof(*s)); + ovs_mutex_init(&s->stats_mutex); + ovs_mutex_init(&s->clear_mutex); + histogram_walls_set_log(&s->cycles, 500, 24000000); + histogram_walls_set_log(&s->pkts, 0, 1000); + histogram_walls_set_lin(&s->cycles_per_pkt, 100, 30000); + histogram_walls_set_lin(&s->pkts_per_batch, 0, 32); + histogram_walls_set_lin(&s->upcalls, 0, 30); + histogram_walls_set_log(&s->cycles_per_upcall, 1000, 1000000); + histogram_walls_set_log(&s->max_vhost_qfill, 0, 512); + s->start_ms = time_msec(); +} + +void +pmd_perf_format_overall_stats(struct ds *str, struct pmd_perf_stats *s, + double duration) +{ + uint64_t stats[PMD_N_STATS]; + double us_per_cycle = 1000000.0 / get_tsc_hz(); + + if (duration == 0) { + return; + } + + pmd_perf_read_counters(s, stats); + uint64_t tot_cycles = stats[PMD_CYCLES_ITER_IDLE] + + stats[PMD_CYCLES_ITER_BUSY]; + uint64_t rx_packets = stats[PMD_STAT_RECV]; + uint64_t tx_packets = stats[PMD_STAT_SENT_PKTS]; + uint64_t tx_batches = stats[PMD_STAT_SENT_BATCHES]; + uint64_t passes = stats[PMD_STAT_RECV] + + stats[PMD_STAT_RECIRC]; + uint64_t upcalls = stats[PMD_STAT_MISS]; + uint64_t upcall_cycles = stats[PMD_CYCLES_UPCALL]; + uint64_t tot_iter = histogram_samples(&s->pkts); + uint64_t idle_iter = s->pkts.bin[0]; + uint64_t busy_iter = tot_iter >= idle_iter ? tot_iter - idle_iter : 0; + + ds_put_format(str, + " Cycles: %12"PRIu64" (%.2f GHz)\n" + " Iterations: %12"PRIu64" (%.2f us/it)\n" + " - idle: %12"PRIu64" (%4.1f %% cycles)\n" + " - busy: %12"PRIu64" (%4.1f %% cycles)\n", + tot_cycles, (tot_cycles / duration) / 1E9, + tot_iter, tot_cycles * us_per_cycle / tot_iter, + idle_iter, + 100.0 * stats[PMD_CYCLES_ITER_IDLE] / tot_cycles, + busy_iter, + 100.0 * stats[PMD_CYCLES_ITER_BUSY] / tot_cycles); + if (rx_packets > 0) { + ds_put_format(str, + " Rx packets: %12"PRIu64" (%.0f Kpps, %.0f cycles/pkt)\n" + " Datapath passes: %12"PRIu64" (%.2f passes/pkt)\n" + " - EMC hits: %12"PRIu64" (%4.1f %%)\n" + " - Megaflow hits: %12"PRIu64" (%4.1f %%, %.2f subtbl lookups/" + "hit)\n" + " - Upcalls: %12"PRIu64" (%4.1f %%, %.1f us/upcall)\n" + " - Lost upcalls: %12"PRIu64" (%4.1f %%)\n", + rx_packets, (rx_packets / duration) / 1000, + 1.0 * stats[PMD_CYCLES_ITER_BUSY] / rx_packets, + passes, rx_packets ? 1.0 * passes / rx_packets : 0, + stats[PMD_STAT_EXACT_HIT], + 100.0 * stats[PMD_STAT_EXACT_HIT] / passes, + stats[PMD_STAT_MASKED_HIT], + 100.0 * stats[PMD_STAT_MASKED_HIT] / passes, + stats[PMD_STAT_MASKED_HIT] + ? 1.0 * stats[PMD_STAT_MASKED_LOOKUP] / stats[PMD_STAT_MASKED_HIT] + : 0, + upcalls, 100.0 * upcalls / passes, + upcalls ? (upcall_cycles * us_per_cycle) / upcalls : 0, + stats[PMD_STAT_LOST], + 100.0 * stats[PMD_STAT_LOST] / passes); + } else { + ds_put_format(str, + " Rx packets: %12"PRIu64"\n", + 0UL); + } + if (tx_packets > 0) { + ds_put_format(str, + " Tx packets: %12"PRIu64" (%.0f Kpps)\n" + " Tx batches: %12"PRIu64" (%.2f pkts/batch)" + "\n", + tx_packets, (tx_packets / duration) / 1000, + tx_batches, 1.0 * tx_packets / tx_batches); + } else { + ds_put_format(str, + " Tx packets: %12"PRIu64"\n" + "\n", + 0UL); + } +} + +void +pmd_perf_format_histograms(struct ds *str, struct pmd_perf_stats *s) +{ + int i; + + ds_put_cstr(str, "Histograms\n"); + ds_put_format(str, + " %-21s %-21s %-21s %-21s %-21s %-21s %-21s\n", + "cycles/it", "packets/it", "cycles/pkt", "pkts/batch", + "max vhost qlen", "upcalls/it", "cycles/upcall"); + for (i = 0; i < NUM_BINS-1; i++) { + ds_put_format(str, + " %-9d %-11"PRIu64" %-9d %-11"PRIu64" %-9d %-11"PRIu64 + " %-9d %-11"PRIu64" %-9d %-11"PRIu64" %-9d %-11"PRIu64 + " %-9d %-11"PRIu64"\n", + s->cycles.wall[i], s->cycles.bin[i], + s->pkts.wall[i],s->pkts.bin[i], + s->cycles_per_pkt.wall[i], s->cycles_per_pkt.bin[i], + s->pkts_per_batch.wall[i], s->pkts_per_batch.bin[i], + s->max_vhost_qfill.wall[i], s->max_vhost_qfill.bin[i], + s->upcalls.wall[i], s->upcalls.bin[i], + s->cycles_per_upcall.wall[i], s->cycles_per_upcall.bin[i]); + } + ds_put_format(str, + " %-9s %-11"PRIu64" %-9s %-11"PRIu64" %-9s %-11"PRIu64 + " %-9s %-11"PRIu64" %-9s %-11"PRIu64" %-9s %-11"PRIu64 + " %-9s %-11"PRIu64"\n", + ">", s->cycles.bin[i], + ">", s->pkts.bin[i], + ">", s->cycles_per_pkt.bin[i], + ">", s->pkts_per_batch.bin[i], + ">", s->max_vhost_qfill.bin[i], + ">", s->upcalls.bin[i], + ">", s->cycles_per_upcall.bin[i]); + if (s->totals.iterations > 0) { + ds_put_cstr(str, + "-----------------------------------------------------" + "-----------------------------------------------------" + "------------------------------------------------\n"); + ds_put_format(str, + " %-21s %-21s %-21s %-21s %-21s %-21s %-21s\n", + "cycles/it", "packets/it", "cycles/pkt", "pkts/batch", + "vhost qlen", "upcalls/it", "cycles/upcall"); + ds_put_format(str, + " %-21"PRIu64" %-21.5f %-21"PRIu64 + " %-21.5f %-21.5f %-21.5f %-21"PRIu32"\n", + s->totals.cycles / s->totals.iterations, + 1.0 * s->totals.pkts / s->totals.iterations, + s->totals.pkts + ? s->totals.busy_cycles / s->totals.pkts : 0, + s->totals.batches + ? 1.0 * s->totals.pkts / s->totals.batches : 0, + 1.0 * s->totals.max_vhost_qfill / s->totals.iterations, + 1.0 * s->totals.upcalls / s->totals.iterations, + s->totals.upcalls + ? s->totals.upcall_cycles / s->totals.upcalls : 0); + } +} + +void +pmd_perf_format_iteration_history(struct ds *str, struct pmd_perf_stats *s, + int n_iter) +{ + struct iter_stats *is; + size_t index; + int i; + + if (n_iter == 0) { + return; + } + ds_put_format(str, " %-17s %-10s %-10s %-10s %-10s " + "%-10s %-10s %-10s\n", + "tsc", "cycles", "packets", "cycles/pkt", "pkts/batch", + "vhost qlen", "upcalls", "cycles/upcall"); + for (i = 1; i <= n_iter; i++) { + index = (s->iterations.idx + HISTORY_LEN - i) % HISTORY_LEN; + is = &s->iterations.sample[index]; + ds_put_format(str, + " %-17"PRIu64" %-11"PRIu64" %-11"PRIu32 + " %-11"PRIu64" %-11"PRIu32" %-11"PRIu32 + " %-11"PRIu32" %-11"PRIu32"\n", + is->timestamp, + is->cycles, + is->pkts, + is->pkts ? is->cycles / is->pkts : 0, + is->batches ? is->pkts / is->batches : 0, + is->max_vhost_qfill, + is->upcalls, + is->upcalls ? is->upcall_cycles / is->upcalls : 0); + } +} + +void +pmd_perf_format_ms_history(struct ds *str, struct pmd_perf_stats *s, int n_ms) +{ + struct iter_stats *is; + size_t index; + int i; + + if (n_ms == 0) { + return; + } + ds_put_format(str, + " %-12s %-10s %-10s %-10s %-10s" + " %-10s %-10s %-10s %-10s\n", + "ms", "iterations", "cycles/it", "Kpps", "cycles/pkt", + "pkts/batch", "vhost qlen", "upcalls", "cycles/upcall"); + for (i = 1; i <= n_ms; i++) { + index = (s->milliseconds.idx + HISTORY_LEN - i) % HISTORY_LEN; + is = &s->milliseconds.sample[index]; + ds_put_format(str, + " %-12"PRIu64" %-11"PRIu32" %-11"PRIu64 + " %-11"PRIu32" %-11"PRIu64" %-11"PRIu32 + " %-11"PRIu32" %-11"PRIu32" %-11"PRIu32"\n", + is->timestamp, + is->iterations, + is->iterations ? is->cycles / is->iterations : 0, + is->pkts, + is->pkts ? is->busy_cycles / is->pkts : 0, + is->batches ? is->pkts / is->batches : 0, + is->iterations + ? is->max_vhost_qfill / is->iterations : 0, + is->upcalls, + is->upcalls ? is->upcall_cycles / is->upcalls : 0); + } } void @@ -51,10 +357,48 @@ pmd_perf_read_counters(struct pmd_perf_stats *s, } } +/* This function clears the PMD performance counters from within the PMD + * thread or from another thread when the PMD thread is not executing its + * poll loop. */ void -pmd_perf_stats_clear(struct pmd_perf_stats *s) +pmd_perf_stats_clear_lock(struct pmd_perf_stats *s) + OVS_REQUIRES(pmd->stats_mutex) { + ovs_mutex_lock(&s->clear_mutex); for (int i = 0; i < PMD_N_STATS; i++) { atomic_read_relaxed(&s->counters.n[i], &s->counters.zero[i]); } + /* The following stats are only applicable in PMD thread and */ + memset(&s->current, 0 , sizeof(struct iter_stats)); + memset(&s->totals, 0 , sizeof(struct iter_stats)); + histogram_clear(&s->cycles); + histogram_clear(&s->pkts); + histogram_clear(&s->cycles_per_pkt); + histogram_clear(&s->upcalls); + histogram_clear(&s->cycles_per_upcall); + histogram_clear(&s->pkts_per_batch); + histogram_clear(&s->max_vhost_qfill); + history_init(&s->iterations); + history_init(&s->milliseconds); + s->start_ms = time_msec(); + s->milliseconds.sample[0].timestamp = s->start_ms; + /* Clearing finished. */ + s->clear = false; + ovs_mutex_unlock(&s->clear_mutex); +} + +/* This function can be called from the anywhere to clear the stats + * of PMD and non-PMD threads. */ +void +pmd_perf_stats_clear(struct pmd_perf_stats *s) +{ + if (ovs_mutex_trylock(&s->stats_mutex) == 0) { + /* Locking successful. PMD not polling. */ + pmd_perf_stats_clear_lock(s); + ovs_mutex_unlock(&s->stats_mutex); + } else { + /* Request the polling PMD to clear the stats. There is no need to + * block here as stats retrieval is prevented during clearing. */ + s->clear = true; + } } diff --git a/lib/dpif-netdev-perf.h b/lib/dpif-netdev-perf.h index 5993c25..b91cb30 100644 --- a/lib/dpif-netdev-perf.h +++ b/lib/dpif-netdev-perf.h @@ -38,10 +38,18 @@ extern "C" { #endif -/* This module encapsulates data structures and functions to maintain PMD - * performance metrics such as packet counters, execution cycles. It - * provides a clean API for dpif-netdev to initialize, update and read and +/* This module encapsulates data structures and functions to maintain basic PMD + * performance metrics such as packet counters, execution cycles as well as + * histograms and time series recording for more detailed PMD metrics. + * + * It provides a clean API for dpif-netdev to initialize, update and read and * reset these metrics. + * + * The basic set of PMD counters is implemented as atomic_uint64_t variables + * to guarantee correct read also in 32-bit systems. + * + * The detailed PMD performance metrics are only supported on 64-bit systems + * with atomic 64-bit read and store semantics for plain uint64_t counters. */ /* Set of counter types maintained in pmd_perf_stats. */ @@ -66,6 +74,7 @@ enum pmd_stat_type { PMD_STAT_SENT_BATCHES, /* Number of batches sent. */ PMD_CYCLES_ITER_IDLE, /* Cycles spent in idle iterations. */ PMD_CYCLES_ITER_BUSY, /* Cycles spent in busy iterations. */ + PMD_CYCLES_UPCALL, /* Cycles spent processing upcalls. */ PMD_N_STATS }; @@ -81,18 +90,87 @@ struct pmd_counters { uint64_t zero[PMD_N_STATS]; /* Value at last _clear(). */ }; -/* Container for all performance metrics of a PMD. - * Part of the struct dp_netdev_pmd_thread. */ +/* Data structure to collect statistical distribution of an integer measurement + * type in form of a histogram. The wall[] array contains the inclusive + * upper boundaries of the bins, while the bin[] array contains the actual + * counters per bin. The histogram walls are typically set automatically + * using the functions provided below.*/ + +#define NUM_BINS 32 /* Number of histogram bins. */ + +struct histogram { + uint32_t wall[NUM_BINS]; + uint64_t bin[NUM_BINS]; +}; + +/* Data structure to record details PMD execution metrics per iteration for + * a history period of up to HISTORY_LEN iterations in circular buffer. + * Also used to record up to HISTORY_LEN millisecond averages/totals of these + * metrics.*/ + +struct iter_stats { + uint64_t timestamp; /* TSC or millisecond. */ + uint64_t cycles; /* Number of TSC cycles spent in it/ms. */ + uint64_t busy_cycles; /* Cycles spent in busy iterations in ms. */ + uint32_t iterations; /* Iterations in ms. */ + uint32_t pkts; /* Packets processed in iteration/ms. */ + uint32_t upcalls; /* Number of upcalls in iteration/ms. */ + uint32_t upcall_cycles; /* Cycles spent in upcalls in iteration/ms. */ + uint32_t batches; /* Number of rx batches in iteration/ms. */ + uint32_t max_vhost_qfill; /* Maximum fill level encountered in it/ms. */ +}; + +#define HISTORY_LEN 1000 /* Length of recorded history + (iterations and ms). */ +#define DEF_HIST_SHOW 20 /* Default number of history samples to + display. */ + +struct history { + size_t idx; /* Slot to which next call to history_store() + will write. */ + struct iter_stats sample[HISTORY_LEN]; +}; + +/* Container for all performance metrics of a PMD within the struct + * dp_netdev_pmd_thread. The metrics must be updated from within the PMD + * thread but can be read from any thread. The basic PMD counters in + * struct pmd_counters can be read without protection against concurrent + * clearing. The other metrics may only be safely read with the clear_mutex + * held to protect against concurrent clearing. */ struct pmd_perf_stats { - /* Start of the current PMD iteration in TSC cycles.*/ - uint64_t start_it_tsc; + /* Prevents interference between PMD polling and stats clearing. */ + struct ovs_mutex stats_mutex; + /* Set by CLI thread to order clearing of PMD stats. */ + volatile bool clear; + /* Prevents stats retrieval while clearing is in progress. */ + struct ovs_mutex clear_mutex; + /* Start of the current performance measurement period. */ + uint64_t start_ms; /* Latest TSC time stamp taken in PMD. */ uint64_t last_tsc; + /* Used to space certain checks in time. */ + uint64_t next_check_tsc; /* If non-NULL, outermost cycle timer currently running in PMD. */ struct cycle_timer *cur_timer; /* Set of PMD counters with their zero offsets. */ struct pmd_counters counters; + /* Statistics of the current iteration. */ + struct iter_stats current; + /* Totals for the current millisecond. */ + struct iter_stats totals; + /* Histograms for the PMD metrics. */ + struct histogram cycles; + struct histogram pkts; + struct histogram cycles_per_pkt; + struct histogram upcalls; + struct histogram cycles_per_upcall; + struct histogram pkts_per_batch; + struct histogram max_vhost_qfill; + /* Iteration history buffer. */ + struct history iterations; + /* Millisecond history buffer. */ + struct history milliseconds; }; /* Support for accurate timing of PMD execution on TSC clock cycle level. @@ -175,8 +253,14 @@ cycle_timer_stop(struct pmd_perf_stats *s, return now - timer->start; } +/* Functions to initialize and reset the PMD performance metrics. */ + void pmd_perf_stats_init(struct pmd_perf_stats *s); void pmd_perf_stats_clear(struct pmd_perf_stats *s); +void pmd_perf_stats_clear_lock(struct pmd_perf_stats *s); + +/* Functions to read and update PMD counters. */ + void pmd_perf_read_counters(struct pmd_perf_stats *s, uint64_t stats[PMD_N_STATS]); @@ -199,32 +283,182 @@ pmd_perf_update_counter(struct pmd_perf_stats *s, atomic_store_relaxed(&s->counters.n[counter], tmp); } +/* Functions to manipulate a sample history. */ + +static inline void +histogram_add_sample(struct histogram *hist, uint32_t val) +{ + /* TODO: Can do better with binary search? */ + for (int i = 0; i < NUM_BINS-1; i++) { + if (val <= hist->wall[i]) { + hist->bin[i]++; + return; + } + } + hist->bin[NUM_BINS-1]++; +} + +uint64_t histogram_samples(const struct histogram *hist); + +/* Add an offset to idx modulo HISTORY_LEN. */ +static inline uint32_t +history_add(uint32_t idx, uint32_t offset) +{ + return (idx + offset) % HISTORY_LEN; +} + +/* Subtract idx2 from idx1 modulo HISTORY_LEN. */ +static inline uint32_t +history_sub(uint32_t idx1, uint32_t idx2) +{ + return (idx1 + HISTORY_LEN - idx2) % HISTORY_LEN; +} + +static inline struct iter_stats * +history_current(struct history *h) +{ + return &h->sample[h->idx]; +} + +static inline struct iter_stats * +history_next(struct history *h) +{ + size_t next_idx = (h->idx + 1) % HISTORY_LEN; + struct iter_stats *next = &h->sample[next_idx]; + + memset(next, 0, sizeof(*next)); + h->idx = next_idx; + return next; +} + +static inline struct iter_stats * +history_store(struct history *h, struct iter_stats *is) +{ + if (is) { + h->sample[h->idx] = *is; + } + /* Advance the history pointer */ + return history_next(h); +} + +/* Functions recording PMD metrics per iteration. */ + static inline void pmd_perf_start_iteration(struct pmd_perf_stats *s) { + if (s->clear) { + /* Clear the PMD stats before starting next iteration. */ + pmd_perf_stats_clear_lock(s); + } + /* Initialize the current interval stats. */ + memset(&s->current, 0, sizeof(struct iter_stats)); if (OVS_LIKELY(s->last_tsc)) { /* We assume here that last_tsc was updated immediately prior at * the end of the previous iteration, or just before the first * iteration. */ - s->start_it_tsc = s->last_tsc; + s->current.timestamp = s->last_tsc; } else { /* In case last_tsc has never been set before. */ - s->start_it_tsc = cycles_counter_update(s); + s->current.timestamp = cycles_counter_update(s); } } static inline void -pmd_perf_end_iteration(struct pmd_perf_stats *s, int rx_packets) +pmd_perf_end_iteration(struct pmd_perf_stats *s, int rx_packets, + int tx_packets, bool full_metrics) { - uint64_t cycles = cycles_counter_update(s) - s->start_it_tsc; + uint64_t now_tsc = cycles_counter_update(s); + struct iter_stats *cum_ms; + uint64_t cycles, cycles_per_pkt = 0; - if (rx_packets > 0) { + cycles = now_tsc - s->current.timestamp; + s->current.cycles = cycles; + s->current.pkts = rx_packets; + + if (rx_packets + tx_packets > 0) { pmd_perf_update_counter(s, PMD_CYCLES_ITER_BUSY, cycles); } else { pmd_perf_update_counter(s, PMD_CYCLES_ITER_IDLE, cycles); } + /* Add iteration samples to histograms. */ + histogram_add_sample(&s->cycles, cycles); + histogram_add_sample(&s->pkts, rx_packets); + + if (!full_metrics) { + return; + } + + s->counters.n[PMD_CYCLES_UPCALL] += s->current.upcall_cycles; + + if (rx_packets > 0) { + cycles_per_pkt = cycles / rx_packets; + histogram_add_sample(&s->cycles_per_pkt, cycles_per_pkt); + } + if (s->current.batches > 0) { + histogram_add_sample(&s->pkts_per_batch, + rx_packets / s->current.batches); + } + histogram_add_sample(&s->upcalls, s->current.upcalls); + if (s->current.upcalls > 0) { + histogram_add_sample(&s->cycles_per_upcall, + s->current.upcall_cycles / s->current.upcalls); + } + histogram_add_sample(&s->max_vhost_qfill, s->current.max_vhost_qfill); + + /* Add iteration samples to millisecond stats. */ + cum_ms = history_current(&s->milliseconds); + cum_ms->iterations++; + cum_ms->cycles += cycles; + if (rx_packets > 0) { + cum_ms->busy_cycles += cycles; + } + cum_ms->pkts += s->current.pkts; + cum_ms->upcalls += s->current.upcalls; + cum_ms->upcall_cycles += s->current.upcall_cycles; + cum_ms->batches += s->current.batches; + cum_ms->max_vhost_qfill += s->current.max_vhost_qfill; + + /* Store in iteration history. This advances the iteration idx and + * clears the next slot in the iteration history. */ + history_store(&s->iterations, &s->current); + if (now_tsc > s->next_check_tsc) { + /* Check if ms is completed and store in milliseconds history. */ + uint64_t now = time_msec(); + if (now != cum_ms->timestamp) { + /* Add ms stats to totals. */ + s->totals.iterations += cum_ms->iterations; + s->totals.cycles += cum_ms->cycles; + s->totals.busy_cycles += cum_ms->busy_cycles; + s->totals.pkts += cum_ms->pkts; + s->totals.upcalls += cum_ms->upcalls; + s->totals.upcall_cycles += cum_ms->upcall_cycles; + s->totals.batches += cum_ms->batches; + s->totals.max_vhost_qfill += cum_ms->max_vhost_qfill; + cum_ms = history_next(&s->milliseconds); + cum_ms->timestamp = now; + } + s->next_check_tsc = cycles_counter_update(s) + 10000; + } } +/* Formatting the output of commands. */ + +struct pmd_perf_params { + int command_type; + bool histograms; + size_t iter_hist_len; + size_t ms_hist_len; +}; + +void pmd_perf_format_overall_stats(struct ds *str, struct pmd_perf_stats *s, + double duration); +void pmd_perf_format_histograms(struct ds *str, struct pmd_perf_stats *s); +void pmd_perf_format_iteration_history(struct ds *str, + struct pmd_perf_stats *s, + int n_iter); +void pmd_perf_format_ms_history(struct ds *str, struct pmd_perf_stats *s, + int n_ms); + #ifdef __cplusplus } #endif diff --git a/lib/dpif-netdev-unixctl.man b/lib/dpif-netdev-unixctl.man new file mode 100644 index 0000000..76c3e4e --- /dev/null +++ b/lib/dpif-netdev-unixctl.man @@ -0,0 +1,157 @@ +.SS "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 \fBdpctl/\fR commands are used), the \fIdp\fR +argument can be omitted. By default the commands present data for all pmd +threads in the datapath. By specifying the "-pmd Core" option one can filter +the output for a single pmd in the datapath. +. +.IP "\fBdpif-netdev/pmd-stats-show\fR [\fB-pmd\fR \fIcore\fR] [\fIdp\fR]" +Shows performance statistics for one or all pmd threads of the datapath +\fIdp\fR. 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 +packet lookups performed by the datapath. Beware that a recirculated packet +experiences one additional lookup per recirculation, so there may be +more lookups than forwarded packets in the datapath. + +Cycles are counted using the TSC or similar facilities (when available on +the platform). The duration of one cycle depends on the processing platform. + +"idle cycles" refers to cycles spent in PMD iterations not forwarding any +any packets. "processing cycles" refers to cycles spent in PMD iterations +forwarding at least one packet, including the cost for polling, processing and +transmitting said packets. + +To reset these counters use \fBdpif-netdev/pmd-stats-clear\fR. +. +.IP "\fBdpif-netdev/pmd-stats-clear\fR [\fIdp\fR]" +Resets to zero the per pmd thread performance numbers shown by the +\fBdpif-netdev/pmd-stats-show\fR and \fBdpif-netdev/pmd-perf-show\fR commands. +It will NOT reset datapath or bridge statistics, only the values shown by +the above commands. +. +.IP "\fBdpif-netdev/pmd-perf-show\fR [\fB-nh\fR] [\fB-it\fR \fIiter_len\fR] \ +[\fB-ms\fR \fIms_len\fR] [\fB-pmd\fR \fIcore\fR] [\fIdp\fR]" +Shows detailed performance metrics for one or all pmds threads of the +user space datapath. + +The collection of detailed statistics can be controlled by a new +configuration parameter "other_config:pmd-perf-metrics". By default it +is disabled. The run-time overhead, when enabled, is in the order of 1%. + +.RS +.IP +.PD .4v +.IP \(em +used cycles +.IP \(em +forwared packets +.IP \(em +number of rx batches +.IP \(em +packets/rx batch +.IP \(em +max. vhostuser queue fill level +.IP \(em +number of upcalls +.IP \(em +cycles spent in upcalls +.PD +.RE +.IP +This raw recorded data is used threefold: + +.RS +.IP +.PD .4v +.IP 1. +In histograms for each of the following metrics: +.RS +.IP \(em +cycles/iteration (logarithmic) +.IP \(em +packets/iteration (logarithmic) +.IP \(em +cycles/packet +.IP \(em +packets/batch +.IP \(em +max. vhostuser qlen (logarithmic) +.IP \(em +upcalls +.IP \(em +cycles/upcall (logarithmic) +The histograms bins are divided linear or logarithmic. +.RE +.IP 2. +A cyclic history of the above metrics for 1024 iterations +.IP 3. +A cyclic history of the cummulative/average values per millisecond wall +clock for the last 1024 milliseconds: +.RS +.IP \(em +number of iterations +.IP \(em +avg. cycles/iteration +.IP \(em +packets (Kpps) +.IP \(em +avg. packets/batch +.IP \(em +avg. max vhost qlen +.IP \(em +upcalls +.IP \(em +avg. cycles/upcall +.RE +.PD +.RE +.IP +. +The command options are: +.RS +.IP "\fB-nh\fR" +Suppress the histograms +.IP "\fB-it\fR \fIiter_len\fR" +Display the last iter_len iteration stats +.IP "\fB-ms\fR \fIms_len\fR" +Display the last ms_len millisecond stats +.RE +.IP +The output always contains the following global PMD statistics: +.RS +.IP +Time: 15:24:55.270 .br +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) +.RE +.IP +Here "Rx packets" actually reflects the number of packets forwarded by the +datapath. "Datapath passes" matches the number of packet lookups as +reported by the \fBdpif-netdev/pmd-stats-show\fR command. + +To reset the counters and start a new measurement use +\fBdpif-netdev/pmd-stats-clear\fR. +. +.IP "\fBdpif-netdev/pmd-rxq-show\fR [\fB-pmd\fR \fIcore\fR] [\fIdp\fR]" +For one or all pmd threads of the datapath \fIdp\fR show the list of queue-ids +with port names, which this thread polls. +. +.IP "\fBdpif-netdev/pmd-rxq-rebalance\fR [\fIdp\fR]" +Reassigns rxqs to pmds in the datapath \fIdp\fR based on their current usage. diff --git a/lib/dpif-netdev.c b/lib/dpif-netdev.c index 4a0fcbd..dbd75e1 100644 --- a/lib/dpif-netdev.c +++ b/lib/dpif-netdev.c @@ -49,6 +49,7 @@ #include "id-pool.h" #include "latch.h" #include "netdev.h" +#include "netdev-provider.h" #include "netdev-vport.h" #include "netlink.h" #include "odp-execute.h" @@ -281,6 +282,8 @@ struct dp_netdev { /* Probability of EMC insertions is a factor of 'emc_insert_min'.*/ OVS_ALIGNED_VAR(CACHE_LINE_SIZE) atomic_uint32_t emc_insert_min; + /* Enable collection of PMD performance metrics. */ + atomic_bool pmd_perf_metrics; /* Protects access to ofproto-dpif-upcall interface during revalidator * thread synchronization. */ @@ -356,6 +359,7 @@ struct dp_netdev_rxq { particular core. */ unsigned intrvl_idx; /* Write index for 'cycles_intrvl'. */ struct dp_netdev_pmd_thread *pmd; /* pmd thread that polls this queue. */ + bool is_vhost; /* Is rxq of a vhost port. */ /* Counters of cycles spent successfully polling and processing pkts. */ atomic_ullong cycles[RXQ_N_CYCLES]; @@ -717,6 +721,8 @@ static inline bool emc_entry_alive(struct emc_entry *ce); static void emc_clear_entry(struct emc_entry *ce); static void dp_netdev_request_reconfigure(struct dp_netdev *dp); +static inline bool +pmd_perf_metrics_enabled(const struct dp_netdev_pmd_thread *pmd); static void emc_cache_init(struct emc_cache *flow_cache) @@ -800,7 +806,8 @@ get_dp_netdev(const struct dpif *dpif) enum pmd_info_type { PMD_INFO_SHOW_STATS, /* Show how cpu cycles are spent. */ PMD_INFO_CLEAR_STATS, /* Set the cycles count to 0. */ - PMD_INFO_SHOW_RXQ /* Show poll-lists of pmd threads. */ + PMD_INFO_SHOW_RXQ, /* Show poll lists of pmd threads. */ + PMD_INFO_PERF_SHOW, /* Show pmd performance details. */ }; static void @@ -891,6 +898,47 @@ pmd_info_show_stats(struct ds *reply, stats[PMD_CYCLES_ITER_BUSY], total_packets); } +static void +pmd_info_show_perf(struct ds *reply, + struct dp_netdev_pmd_thread *pmd, + struct pmd_perf_params *par) +{ + if (pmd->core_id != NON_PMD_CORE_ID) { + char *time_str = + xastrftime_msec("%H:%M:%S.###", time_wall_msec(), true); + long long now = time_msec(); + double duration = (now - pmd->perf_stats.start_ms) / 1000.0; + + ds_put_cstr(reply, "\n"); + ds_put_format(reply, "Time: %s\n", time_str); + ds_put_format(reply, "Measurement duration: %.3f s\n", duration); + ds_put_cstr(reply, "\n"); + format_pmd_thread(reply, pmd); + ds_put_cstr(reply, "\n"); + pmd_perf_format_overall_stats(reply, &pmd->perf_stats, duration); + if (pmd_perf_metrics_enabled(pmd)) { + /* Prevent parallel clearing of perf metrics. */ + ovs_mutex_lock(&pmd->perf_stats.clear_mutex); + if (par->histograms) { + ds_put_cstr(reply, "\n"); + pmd_perf_format_histograms(reply, &pmd->perf_stats); + } + if (par->iter_hist_len > 0) { + ds_put_cstr(reply, "\n"); + pmd_perf_format_iteration_history(reply, &pmd->perf_stats, + par->iter_hist_len); + } + if (par->ms_hist_len > 0) { + ds_put_cstr(reply, "\n"); + pmd_perf_format_ms_history(reply, &pmd->perf_stats, + par->ms_hist_len); + } + ovs_mutex_unlock(&pmd->perf_stats.clear_mutex); + } + free(time_str); + } +} + static int compare_poll_list(const void *a_, const void *b_) { @@ -1068,7 +1116,7 @@ dpif_netdev_pmd_info(struct unixctl_conn *conn, int argc, const char *argv[], ovs_mutex_lock(&dp_netdev_mutex); while (argc > 1) { - if (!strcmp(argv[1], "-pmd") && argc >= 3) { + if (!strcmp(argv[1], "-pmd") && argc > 2) { if (str_to_uint(argv[2], 10, &core_id)) { filter_on_pmd = true; } @@ -1108,6 +1156,8 @@ dpif_netdev_pmd_info(struct unixctl_conn *conn, int argc, const char *argv[], pmd_perf_stats_clear(&pmd->perf_stats); } else if (type == PMD_INFO_SHOW_STATS) { pmd_info_show_stats(&reply, pmd); + } else if (type == PMD_INFO_PERF_SHOW) { + pmd_info_show_perf(&reply, pmd, (struct pmd_perf_params *)aux); } } free(pmd_list); @@ -1117,6 +1167,48 @@ dpif_netdev_pmd_info(struct unixctl_conn *conn, int argc, const char *argv[], unixctl_command_reply(conn, ds_cstr(&reply)); ds_destroy(&reply); } + +static void +pmd_perf_show_cmd(struct unixctl_conn *conn, int argc, + const char *argv[], + void *aux OVS_UNUSED) +{ + struct pmd_perf_params par; + long int it_hist = 0, ms_hist = 0; + par.histograms = true; + + while (argc > 1) { + if (!strcmp(argv[1], "-nh")) { + par.histograms = false; + argc -= 1; + argv += 1; + } else if (!strcmp(argv[1], "-it") && argc > 2) { + it_hist = strtol(argv[2], NULL, 10); + if (it_hist < 0) { + it_hist = 0; + } else if (it_hist > HISTORY_LEN) { + it_hist = HISTORY_LEN; + } + argc -= 2; + argv += 2; + } else if (!strcmp(argv[1], "-ms") && argc > 2) { + ms_hist = strtol(argv[2], NULL, 10); + if (ms_hist < 0) { + ms_hist = 0; + } else if (ms_hist > HISTORY_LEN) { + ms_hist = HISTORY_LEN; + } + argc -= 2; + argv += 2; + } else { + break; + } + } + par.iter_hist_len = it_hist; + par.ms_hist_len = ms_hist; + par.command_type = PMD_INFO_PERF_SHOW; + dpif_netdev_pmd_info(conn, argc, argv, &par); +} static int dpif_netdev_init(void) @@ -1134,6 +1226,12 @@ dpif_netdev_init(void) unixctl_command_register("dpif-netdev/pmd-rxq-show", "[-pmd core] [dp]", 0, 3, dpif_netdev_pmd_info, (void *)&poll_aux); + unixctl_command_register("dpif-netdev/pmd-perf-show", + "[-nh] [-it iter-history-len]" + " [-ms ms-history-len]" + " [-pmd core] [dp]", + 0, 8, pmd_perf_show_cmd, + NULL); unixctl_command_register("dpif-netdev/pmd-rxq-rebalance", "[dp]", 0, 1, dpif_netdev_pmd_rebalance, NULL); @@ -3020,6 +3118,18 @@ dpif_netdev_set_config(struct dpif *dpif, const struct smap *other_config) } } + bool perf_enabled = smap_get_bool(other_config, "pmd-perf-metrics", false); + bool cur_perf_enabled; + atomic_read_relaxed(&dp->pmd_perf_metrics, &cur_perf_enabled); + if (perf_enabled != cur_perf_enabled) { + atomic_store_relaxed(&dp->pmd_perf_metrics, perf_enabled); + if (perf_enabled) { + VLOG_INFO("PMD performance metrics collection enabled"); + } else { + VLOG_INFO("PMD performance metrics collection disabled"); + } + } + return 0; } @@ -3189,6 +3299,20 @@ dp_netdev_rxq_get_intrvl_cycles(struct dp_netdev_rxq *rx, unsigned idx) return processing_cycles; } +static inline bool +pmd_perf_metrics_enabled(const struct dp_netdev_pmd_thread *pmd) +{ + /* If stores and reads of 64-bit integers are not atomic, the + * full PMD performance metrics are not available as locked + * access to 64 bit integers would be prohibitively expensive. */ + if (sizeof(uint64_t) > sizeof(void *)) { + return false; + } + bool pmd_perf_enabled; + atomic_read_relaxed(&pmd->dp->pmd_perf_metrics, &pmd_perf_enabled); + return pmd_perf_enabled; +} + static int dp_netdev_pmd_flush_output_on_port(struct dp_netdev_pmd_thread *pmd, struct tx_port *p) @@ -3264,10 +3388,12 @@ dp_netdev_process_rxq_port(struct dp_netdev_pmd_thread *pmd, struct dp_netdev_rxq *rxq, odp_port_t port_no) { + struct pmd_perf_stats *s = &pmd->perf_stats; struct dp_packet_batch batch; struct cycle_timer timer; int error; - int batch_cnt = 0, output_cnt = 0; + int batch_cnt = 0; + int rem_qlen = 0, *qlen_p= NULL; uint64_t cycles; /* Measure duration for polling and processing rx burst. */ @@ -3276,20 +3402,37 @@ dp_netdev_process_rxq_port(struct dp_netdev_pmd_thread *pmd, pmd->ctx.last_rxq = rxq; dp_packet_batch_init(&batch); - error = netdev_rxq_recv(rxq->rx, &batch, NULL); + /* Fetch the rx queue length only for vhostuser ports. */ + if (pmd_perf_metrics_enabled(pmd) && rxq->is_vhost) { + qlen_p = &rem_qlen; + } + + error = netdev_rxq_recv(rxq->rx, &batch, qlen_p); if (!error) { /* At least one packet received. */ *recirc_depth_get() = 0; pmd_thread_ctx_time_update(pmd); - batch_cnt = batch.count; + if (pmd_perf_metrics_enabled(pmd)) { + /* Update batch histogram. */ + s->current.batches++; + histogram_add_sample(&s->pkts_per_batch, batch_cnt); + /* Update the maximum vhost rx queue fill level. */ + if (rxq->is_vhost && rem_qlen >= 0) { + uint32_t qfill = batch_cnt + rem_qlen; + if (qfill > s->current.max_vhost_qfill) { + s->current.max_vhost_qfill = qfill; + } + } + } + /* Process packet batch. */ dp_netdev_input(pmd, &batch, port_no); /* Assign processing cycles to rx queue. */ cycles = cycle_timer_stop(&pmd->perf_stats, &timer); dp_netdev_rxq_add_cycles(rxq, RXQ_CYCLES_PROC_CURR, cycles); - output_cnt = dp_netdev_pmd_flush_output_packets(pmd, false); + dp_netdev_pmd_flush_output_packets(pmd, false); } else { /* Discard cycles. */ cycle_timer_stop(&pmd->perf_stats, &timer); @@ -3303,7 +3446,7 @@ dp_netdev_process_rxq_port(struct dp_netdev_pmd_thread *pmd, pmd->ctx.last_rxq = NULL; - return batch_cnt + output_cnt; + return batch_cnt; } static struct tx_port * @@ -3359,6 +3502,7 @@ port_reconfigure(struct dp_netdev_port *port) } port->rxqs[i].port = port; + port->rxqs[i].is_vhost = !strncmp(port->type, "dpdkvhost", 9); err = netdev_rxq_open(netdev, &port->rxqs[i].rx, i); if (err) { @@ -4137,23 +4281,26 @@ reload: pmd->intrvl_tsc_prev = 0; atomic_store_relaxed(&pmd->intrvl_cycles, 0); cycles_counter_update(s); + /* Protect pmd stats from external clearing while polling. */ + ovs_mutex_lock(&pmd->perf_stats.stats_mutex); for (;;) { - uint64_t iter_packets = 0; + uint64_t rx_packets = 0, tx_packets = 0; pmd_perf_start_iteration(s); + for (i = 0; i < poll_cnt; i++) { process_packets = dp_netdev_process_rxq_port(pmd, poll_list[i].rxq, poll_list[i].port_no); - iter_packets += process_packets; + rx_packets += process_packets; } - if (!iter_packets) { + if (!rx_packets) { /* We didn't receive anything in the process loop. * Check if we need to send something. * There was no time updates on current iteration. */ pmd_thread_ctx_time_update(pmd); - iter_packets += dp_netdev_pmd_flush_output_packets(pmd, false); + tx_packets = dp_netdev_pmd_flush_output_packets(pmd, false); } if (lc++ > 1024) { @@ -4172,8 +4319,10 @@ reload: break; } } - pmd_perf_end_iteration(s, iter_packets); + pmd_perf_end_iteration(s, rx_packets, tx_packets, + pmd_perf_metrics_enabled(pmd)); } + ovs_mutex_unlock(&pmd->perf_stats.stats_mutex); poll_cnt = pmd_load_queues_and_ports(pmd, &poll_list); exiting = latch_is_set(&pmd->exit_latch); @@ -5069,6 +5218,7 @@ handle_packet_upcall(struct dp_netdev_pmd_thread *pmd, struct match match; ovs_u128 ufid; int error; + uint64_t cycles = cycles_counter_update(&pmd->perf_stats); match.tun_md.valid = false; miniflow_expand(&key->mf, &match.flow); @@ -5122,6 +5272,14 @@ handle_packet_upcall(struct dp_netdev_pmd_thread *pmd, ovs_mutex_unlock(&pmd->flow_mutex); emc_probabilistic_insert(pmd, key, netdev_flow); } + if (pmd_perf_metrics_enabled(pmd)) { + /* Update upcall stats. */ + cycles = cycles_counter_update(&pmd->perf_stats) - cycles; + struct pmd_perf_stats *s = &pmd->perf_stats; + s->current.upcalls++; + s->current.upcall_cycles += cycles; + histogram_add_sample(&s->cycles_per_upcall, cycles); + } return error; } diff --git a/manpages.mk b/manpages.mk index 351155f..761fd9a 100644 --- a/manpages.mk +++ b/manpages.mk @@ -254,6 +254,7 @@ vswitchd/ovs-vswitchd.8: \ lib/coverage-unixctl.man \ lib/daemon.man \ lib/dpctl.man \ + lib/dpif-netdev-unixctl.man \ lib/memory-unixctl.man \ lib/netdev-dpdk-unixctl.man \ lib/service.man \ @@ -270,6 +271,7 @@ lib/common.man: lib/coverage-unixctl.man: lib/daemon.man: lib/dpctl.man: +lib/dpif-netdev-unixctl.man: lib/memory-unixctl.man: lib/netdev-dpdk-unixctl.man: lib/service.man: diff --git a/vswitchd/ovs-vswitchd.8.in b/vswitchd/ovs-vswitchd.8.in index 80e5f53..8b4034d 100644 --- a/vswitchd/ovs-vswitchd.8.in +++ b/vswitchd/ovs-vswitchd.8.in @@ -256,32 +256,7 @@ type). .. .so lib/dpctl.man . -.SS "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 \fBdpctl/\fR commands are used), the \fIdp\fR -argument can be omitted. -.IP "\fBdpif-netdev/pmd-stats-show\fR [\fIdp\fR]" -Shows performance statistics for each pmd thread of the datapath \fIdp\fR. -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 -\fBdpif-netdev/pmd-stats-clear\fR. The duration of one cycle depends on the -measuring infrastructure. ``idle cycles'' refers to cycles spent polling -devices but not receiving any packets. ``processing cycles'' refers to cycles -spent polling devices and successfully receiving packets, plus the cycles -spent processing said packets. -.IP "\fBdpif-netdev/pmd-stats-clear\fR [\fIdp\fR]" -Resets to zero the per pmd thread performance numbers shown by the -\fBdpif-netdev/pmd-stats-show\fR command. It will NOT reset datapath or -bridge statistics, only the values shown by the above command. -.IP "\fBdpif-netdev/pmd-rxq-show\fR [\fIdp\fR]" -For each pmd thread of the datapath \fIdp\fR shows list of queue-ids with -port names, which this thread polls. -.IP "\fBdpif-netdev/pmd-rxq-rebalance\fR [\fIdp\fR]" -Reassigns rxqs to pmds in the datapath \fIdp\fR based on their current usage. -. +.so lib/dpif-netdev-unixctl.man .so lib/netdev-dpdk-unixctl.man .so ofproto/ofproto-dpif-unixctl.man .so ofproto/ofproto-unixctl.man diff --git a/vswitchd/vswitch.xml b/vswitchd/vswitch.xml index 7e89325..46eb9e3 100644 --- a/vswitchd/vswitch.xml +++ b/vswitchd/vswitch.xml @@ -375,6 +375,18 @@ </p> </column> + <column name="other_config" key="pmd-perf-metrics" + type='{"type": "boolean"}'> + <p> + Enables recording of detailed PMD performance metrics for analysis + and trouble-shooting. This can have a performance impact in the + order of 1%. + </p> + <p> + Defaults to false but can be changed at any time. + </p> + </column> + <column name="other_config" key="n-handler-threads" type='{"type": "integer", "minInteger": 1}'> <p> -- 1.9.1 _______________________________________________ dev mailing list d...@openvswitch.org https://mail.openvswitch.org/mailman/listinfo/ovs-dev