LXR qemu/migration/migration-stats.h

   1/*
   2 * Migration stats
   3 *
   4 * Copyright (c) 2012-2023 Red Hat Inc
   5 *
   6 * Authors:
   7 *  Juan Quintela <quintela@redhat.com>
   8 *
   9 * This work is licensed under the terms of the GNU GPL, version 2 or later.
  10 * See the COPYING file in the top-level directory.
  11 */
  12
  13#ifndef QEMU_MIGRATION_STATS_H
  14#define QEMU_MIGRATION_STATS_H
  15
  16#include "qemu/stats64.h"
  17
  18/*
  19 * Amount of time to allocate to each "chunk" of bandwidth-throttled
  20 * data.
  21 */
  22#define BUFFER_DELAY     100
  23
  24/*
  25 * If rate_limit_max is 0, there is special code to remove the rate
  26 * limit.
  27 */
  28#define RATE_LIMIT_DISABLED 0
  29
  30/*
  31 * These are the ram migration statistic counters.  It is loosely
  32 * based on MigrationStats.  We change to Stat64 any counter that
  33 * needs to be updated using atomic ops (can be accessed by more than
  34 * one thread).
  35 */
  36typedef struct {
  37    /*
  38     * Number of bytes that were dirty last time that we synced with
  39     * the guest memory.  We use that to calculate the downtime.  As
  40     * the remaining dirty amounts to what we know that is still dirty
  41     * since last iteration, not counting what the guest has dirtied
  42     * since we synchronized bitmaps.
  43     */
  44    Stat64 dirty_bytes_last_sync;
  45    /*
  46     * Number of pages dirtied per second.
  47     */
  48    Stat64 dirty_pages_rate;
  49    /*
  50     * Number of times we have synchronized guest bitmaps.
  51     */
  52    Stat64 dirty_sync_count;
  53    /*
  54     * Number of times zero copy failed to send any page using zero
  55     * copy.
  56     */
  57    Stat64 dirty_sync_missed_zero_copy;
  58    /*
  59     * Number of bytes sent at migration completion stage while the
  60     * guest is stopped.
  61     */
  62    Stat64 downtime_bytes;
  63    /*
  64     * Number of bytes sent through multifd channels.
  65     */
  66    Stat64 multifd_bytes;
  67    /*
  68     * Number of pages transferred that were not full of zeros.
  69     */
  70    Stat64 normal_pages;
  71    /*
  72     * Number of bytes sent during postcopy.
  73     */
  74    Stat64 postcopy_bytes;
  75    /*
  76     * Number of postcopy page faults that we have handled during
  77     * postcopy stage.
  78     */
  79    Stat64 postcopy_requests;
  80    /*
  81     * Number of bytes sent during precopy stage.
  82     */
  83    Stat64 precopy_bytes;
  84    /*
  85     * Number of bytes transferred with QEMUFile.
  86     */
  87    Stat64 qemu_file_transferred;
  88    /*
  89     * Amount of transferred data at the start of current cycle.
  90     */
  91    Stat64 rate_limit_start;
  92    /*
  93     * Maximum amount of data we can send in a cycle.
  94     */
  95    Stat64 rate_limit_max;
  96    /*
  97     * Number of bytes sent through RDMA.
  98     */
  99    Stat64 rdma_bytes;
 100    /*
 101     * Number of pages transferred that were full of zeros.
 102     */
 103    Stat64 zero_pages;
 104} MigrationAtomicStats;
 105
 106extern MigrationAtomicStats mig_stats;
 107
 108/**
 109 * migration_rate_get: Get the maximum amount that can be transferred.
 110 *
 111 * Returns the maximum number of bytes that can be transferred in a cycle.
 112 */
 113uint64_t migration_rate_get(void);
 114
 115/**
 116 * migration_rate_reset: Reset the rate limit counter.
 117 *
 118 * This is called when we know we start a new transfer cycle.
 119 */
 120void migration_rate_reset(void);
 121
 122/**
 123 * migration_rate_set: Set the maximum amount that can be transferred.
 124 *
 125 * Sets the maximum amount of bytes that can be transferred in one cycle.
 126 *
 127 * @new_rate: new maximum amount
 128 */
 129void migration_rate_set(uint64_t new_rate);
 130
 131/**
 132 * migration_transferred_bytes: Return number of bytes transferred
 133 *
 134 * Returns how many bytes have we transferred since the beginning of
 135 * the migration.  It accounts for bytes sent through any migration
 136 * channel, multifd, qemu_file, rdma, ....
 137 */
 138uint64_t migration_transferred_bytes(void);
 139#endif
 140