Inside Bitcoin

1#!/usr/bin/env bpftrace
2
3/*
4
5  USAGE:
6
7  bpftrace contrib/tracing/connectblock_benchmark.bt <start height> <end height> <logging threshold in ms>
8
9  - <start height> sets the height at which the benchmark should start. Setting
10    the start height to 0 starts the benchmark immediately, even before the
11    first block is connected.
12  - <end height> sets the height after which the benchmark should end. Setting
13    the end height to 0 disables the benchmark. The script only logs blocks
14    over <logging threshold in ms>.
15  - Threshold <logging threshold in ms>
16
17  This script requires a 'bitcoind' binary compiled with eBPF support and the
18  'validation:block_connected' USDT. By default, it's assumed that 'bitcoind' is
19  located in './build/bin/bitcoind'. This can be modified in the script below.
20
21  EXAMPLES:
22
23  bpftrace contrib/tracing/connectblock_benchmark.bt 300000 680000 1000
24
25  When run together 'bitcoind -reindex', this benchmarks the time it takes to
26  connect the blocks between height 300.000 and 680.000 (inclusive) and prints
27  details about all blocks that take longer than 1000ms to connect. Prints a
28  histogram with block connection times when the benchmark is finished.
29
30
31  bpftrace contrib/tracing/connectblock_benchmark.bt 0 0 500
32
33  When running together 'bitcoind', all newly connected blocks that
34  take longer than 500ms to connect are logged. A histogram with block
35  connection times is shown when the script is terminated.
36
37*/
38
39BEGIN
40{
41  $start_height = $1;
42  $end_height = $2;
43  $logging_threshold_ms = $3;
44
45  if ($end_height < $start_height) {
46    printf("Error: start height (%d) larger than end height (%d)!\n", $start_height, $end_height);
47    exit();
48  }
49
50  if ($end_height > 0) {
51    printf("ConnectBlock benchmark between height %d and %d inclusive\n", $start_height, $end_height);
52  } else {
53    printf("ConnectBlock logging starting at height %d\n", $start_height);
54  }
55
56  if ($logging_threshold_ms > 0) {
57    printf("Logging blocks taking longer than %d ms to connect.\n", $3);
58  }
59
60  if ($start_height == 0) {
61    @start = nsecs;
62  }
63}
64
65/*
66  Attaches to the 'validation:block_connected' USDT and collects stats when the
67  connected block is between the start and end height (or the end height is
68  unset).
69*/
70usdt:./build/bin/bitcoind:validation:block_connected /arg1 >= $1 && (arg1 <= $2 || $2 == 0 )/
71{
72  $height = arg1;
73  $transactions = arg2;
74  $inputs = arg3;
75  $sigops =  arg4;
76  $duration = (uint64) arg5;
77
78  @height = $height;
79
80  @blocks = @blocks + 1;
81  @transactions = @transactions + $transactions;
82  @inputs = @inputs + $inputs;
83  @sigops = @sigops + $sigops;
84
85  @durations = hist($duration / 1e6);
86
87  if ($height == $1 && $height != 0) {
88    @start = nsecs;
89    printf("Starting Connect Block Benchmark between height %d and %d.\n", $1, $2);
90  }
91
92  if ($2 > 0 && $height >= $2) {
93    @end = nsecs;
94    $duration = @end - @start;
95    printf("\nTook %d ms to connect the blocks between height %d and %d.\n", $duration / 1e9, $1, $2);
96    exit();
97  }
98}
99
100/*
101  Attaches to the 'validation:block_connected' USDT and logs information about
102  blocks where the time it took to connect the block is above the
103  <logging threshold in ms>.
104*/
105usdt:./build/bin/bitcoind:validation:block_connected / (uint64) arg5 / 1e6 > $3 /
106{
107  $hash = arg0;
108  $height = (int32) arg1;
109  $transactions = (uint64) arg2;
110  $inputs = (int32) arg3;
111  $sigops = (int64) arg4;
112  $duration = (int64) arg5;
113
114
115  printf("Block %d (", $height);
116  /* Prints each byte of the block hash as hex in big-endian (the block-explorer format) */
117  $p = $hash + 31;
118  unroll(32) {
119      $b = *(uint8*)$p;
120      printf("%02x", $b);
121      $p -= 1;
122  }
123  printf(")  %4d tx  %5d ins  %5d sigops  took %4d ms\n", $transactions, $inputs, $sigops, (uint64) $duration / 1e6);
124}
125
126
127/*
128  Prints stats about the blocks, transactions, inputs, and sigops processed in
129  the last second (if any).
130*/
131interval:s:1 {
132  if (@blocks > 0) {
133    printf("BENCH %4d blk/s %6d tx/s %7d inputs/s %8d sigops/s (height %d)\n", @blocks, @transactions, @inputs, @sigops, @height);
134
135    zero(@blocks);
136    zero(@transactions);
137    zero(@inputs);
138    zero(@sigops);
139  }
140}
141
142END
143{
144  printf("\nHistogram of block connection times in milliseconds (ms).\n");
145  print(@durations);
146
147  clear(@durations);
148  clear(@blocks);
149  clear(@transactions);
150  clear(@inputs);
151  clear(@sigops);
152  clear(@height);
153  clear(@start);
154  clear(@end);
155}
156
157