unixtest | 57abe5b | 2016-01-31 10:47:03 +0000 | [diff] [blame] | 1 | #!/usr/bin/python |
| 2 | # |
| 3 | # cachestat Count cache kernel function calls. |
| 4 | # For Linux, uses BCC, eBPF. See .c file. |
| 5 | # |
| 6 | # USAGE: cachestat |
| 7 | # Taken from funccount by Brendan Gregg |
| 8 | # This is a rewrite of cachestat from perf to bcc |
| 9 | # https://github.com/brendangregg/perf-tools/blob/master/fs/cachestat |
| 10 | # |
| 11 | # Copyright (c) 2016 Allan McAleavy. |
| 12 | # Copyright (c) 2015 Brendan Gregg. |
| 13 | # Licensed under the Apache License, Version 2.0 (the "License") |
| 14 | # |
| 15 | # 09-Sep-2015 Brendan Gregg Created this. |
| 16 | # 06-Nov-2015 Allan McAleavy |
| 17 | # 13-Jan-2016 Allan McAleavy run pep8 against program |
| 18 | |
| 19 | from __future__ import print_function |
| 20 | from bcc import BPF |
| 21 | from time import sleep, strftime |
| 22 | import signal |
| 23 | import re |
| 24 | from sys import argv |
| 25 | |
| 26 | # signal handler |
| 27 | def signal_ignore(signal, frame): |
| 28 | print() |
| 29 | |
| 30 | # Function to gather data from /proc/meminfo |
| 31 | # return dictionary for quicker lookup of both values |
| 32 | def get_meminfo(): |
| 33 | result = dict() |
| 34 | |
| 35 | for line in open('/proc/meminfo'): |
| 36 | k = line.split(':', 3) |
| 37 | v = k[1].split() |
| 38 | result[k[0]] = int(v[0]) |
| 39 | return result |
| 40 | |
| 41 | # set global variables |
unixtest | 57abe5b | 2016-01-31 10:47:03 +0000 | [diff] [blame] | 42 | mpa = 0 |
| 43 | mbd = 0 |
| 44 | apcl = 0 |
| 45 | apd = 0 |
Joel Fernandes | 2b34870 | 2018-02-27 20:38:42 -0800 | [diff] [blame] | 46 | total = 0 |
unixtest | 57abe5b | 2016-01-31 10:47:03 +0000 | [diff] [blame] | 47 | misses = 0 |
Joel Fernandes | 2b34870 | 2018-02-27 20:38:42 -0800 | [diff] [blame] | 48 | hits = 0 |
unixtest | 57abe5b | 2016-01-31 10:47:03 +0000 | [diff] [blame] | 49 | debug = 0 |
| 50 | |
| 51 | # args |
| 52 | def usage(): |
| 53 | print("USAGE: %s [-T] [ interval [count] ]" % argv[0]) |
| 54 | exit() |
| 55 | |
| 56 | # arguments |
| 57 | interval = 5 |
| 58 | count = -1 |
| 59 | tstamp = 0 |
| 60 | |
| 61 | if len(argv) > 1: |
| 62 | if str(argv[1]) == '-T': |
| 63 | tstamp = 1 |
| 64 | |
| 65 | if len(argv) > 1 and tstamp == 0: |
| 66 | try: |
| 67 | if int(argv[1]) > 0: |
| 68 | interval = int(argv[1]) |
| 69 | if len(argv) > 2: |
| 70 | if int(argv[2]) > 0: |
| 71 | count = int(argv[2]) |
| 72 | except: |
| 73 | usage() |
| 74 | |
| 75 | elif len(argv) > 2 and tstamp == 1: |
| 76 | try: |
| 77 | if int(argv[2]) > 0: |
| 78 | interval = int(argv[2]) |
| 79 | if len(argv) >= 4: |
| 80 | if int(argv[3]) > 0: |
| 81 | count = int(argv[3]) |
| 82 | except: |
| 83 | usage() |
| 84 | |
| 85 | # load BPF program |
| 86 | bpf_text = """ |
| 87 | |
| 88 | #include <uapi/linux/ptrace.h> |
| 89 | struct key_t { |
| 90 | u64 ip; |
| 91 | }; |
| 92 | |
| 93 | BPF_HASH(counts, struct key_t); |
| 94 | |
| 95 | int do_count(struct pt_regs *ctx) { |
| 96 | struct key_t key = {}; |
| 97 | u64 zero = 0, *val; |
| 98 | u64 ip; |
| 99 | |
Naveen N. Rao | 4afa96a | 2016-05-03 14:54:21 +0530 | [diff] [blame] | 100 | key.ip = PT_REGS_IP(ctx); |
unixtest | 57abe5b | 2016-01-31 10:47:03 +0000 | [diff] [blame] | 101 | val = counts.lookup_or_init(&key, &zero); // update counter |
| 102 | (*val)++; |
| 103 | return 0; |
| 104 | } |
| 105 | |
| 106 | """ |
| 107 | b = BPF(text=bpf_text) |
| 108 | b.attach_kprobe(event="add_to_page_cache_lru", fn_name="do_count") |
| 109 | b.attach_kprobe(event="mark_page_accessed", fn_name="do_count") |
| 110 | b.attach_kprobe(event="account_page_dirtied", fn_name="do_count") |
| 111 | b.attach_kprobe(event="mark_buffer_dirty", fn_name="do_count") |
| 112 | |
| 113 | # header |
| 114 | if tstamp: |
| 115 | print("%-8s " % "TIME", end="") |
Joel Fernandes | 2b34870 | 2018-02-27 20:38:42 -0800 | [diff] [blame] | 116 | print("%8s %8s %8s %8s %12s %10s" % |
| 117 | ("TOTAL", "MISSES", "HITS", "DIRTIES", "BUFFERS_MB", "CACHED_MB")) |
unixtest | 57abe5b | 2016-01-31 10:47:03 +0000 | [diff] [blame] | 118 | |
| 119 | loop = 0 |
| 120 | exiting = 0 |
| 121 | while 1: |
| 122 | if count > 0: |
| 123 | loop += 1 |
| 124 | if loop > count: |
| 125 | exit() |
| 126 | |
| 127 | try: |
| 128 | sleep(interval) |
| 129 | except KeyboardInterrupt: |
| 130 | exiting = 1 |
| 131 | # as cleanup can take many seconds, trap Ctrl-C: |
| 132 | signal.signal(signal.SIGINT, signal_ignore) |
| 133 | |
| 134 | counts = b.get_table("counts") |
| 135 | for k, v in sorted(counts.items(), key=lambda counts: counts[1].value): |
| 136 | |
Brenden Blanco | 42d6098 | 2017-04-24 14:31:28 -0700 | [diff] [blame] | 137 | if re.match(b'mark_page_accessed', b.ksym(k.ip)) is not None: |
chantra | a2d669c | 2016-07-29 14:10:15 -0700 | [diff] [blame] | 138 | mpa = max(0, v.value) |
unixtest | 57abe5b | 2016-01-31 10:47:03 +0000 | [diff] [blame] | 139 | |
Brenden Blanco | 42d6098 | 2017-04-24 14:31:28 -0700 | [diff] [blame] | 140 | if re.match(b'mark_buffer_dirty', b.ksym(k.ip)) is not None: |
chantra | a2d669c | 2016-07-29 14:10:15 -0700 | [diff] [blame] | 141 | mbd = max(0, v.value) |
unixtest | 57abe5b | 2016-01-31 10:47:03 +0000 | [diff] [blame] | 142 | |
Brenden Blanco | 42d6098 | 2017-04-24 14:31:28 -0700 | [diff] [blame] | 143 | if re.match(b'add_to_page_cache_lru', b.ksym(k.ip)) is not None: |
chantra | a2d669c | 2016-07-29 14:10:15 -0700 | [diff] [blame] | 144 | apcl = max(0, v.value) |
unixtest | 57abe5b | 2016-01-31 10:47:03 +0000 | [diff] [blame] | 145 | |
Brenden Blanco | 42d6098 | 2017-04-24 14:31:28 -0700 | [diff] [blame] | 146 | if re.match(b'account_page_dirtied', b.ksym(k.ip)) is not None: |
chantra | a2d669c | 2016-07-29 14:10:15 -0700 | [diff] [blame] | 147 | apd = max(0, v.value) |
unixtest | 57abe5b | 2016-01-31 10:47:03 +0000 | [diff] [blame] | 148 | |
Joel Fernandes | 2b34870 | 2018-02-27 20:38:42 -0800 | [diff] [blame] | 149 | # total = total cache accesses without counting dirties |
| 150 | # misses = total of add to lru because of read misses |
| 151 | total = (mpa - mbd) |
| 152 | misses = (apcl - apd) |
unixtest | 57abe5b | 2016-01-31 10:47:03 +0000 | [diff] [blame] | 153 | |
Joel Fernandes | 2b34870 | 2018-02-27 20:38:42 -0800 | [diff] [blame] | 154 | if total < 0: |
| 155 | total = 0 |
unixtest | 57abe5b | 2016-01-31 10:47:03 +0000 | [diff] [blame] | 156 | |
Joel Fernandes | 2b34870 | 2018-02-27 20:38:42 -0800 | [diff] [blame] | 157 | if misses < 0: |
| 158 | misses = 0 |
| 159 | |
| 160 | hits = total - misses |
| 161 | |
| 162 | # If hits are < 0, then its possible misses are overestimated |
| 163 | # due to possibly page cache read ahead adding more pages than |
| 164 | # needed. In this case just assume misses as total and reset hits. |
| 165 | if hits < 0: |
| 166 | misses = total |
| 167 | hits = 0 |
unixtest | 57abe5b | 2016-01-31 10:47:03 +0000 | [diff] [blame] | 168 | |
| 169 | if debug: |
Joel Fernandes | 2b34870 | 2018-02-27 20:38:42 -0800 | [diff] [blame] | 170 | print("%d %d %d %d %d %d %d\n" % |
| 171 | (mpa, mbd, apcl, apd, total, misses, hits)) |
unixtest | 57abe5b | 2016-01-31 10:47:03 +0000 | [diff] [blame] | 172 | |
| 173 | counts.clear() |
| 174 | |
| 175 | # Get memory info |
| 176 | mem = get_meminfo() |
| 177 | cached = int(mem["Cached"]) / 1024 |
| 178 | buff = int(mem["Buffers"]) / 1024 |
| 179 | |
| 180 | if tstamp == 1: |
| 181 | print("%-8s " % strftime("%H:%M:%S"), end="") |
Joel Fernandes | 2b34870 | 2018-02-27 20:38:42 -0800 | [diff] [blame] | 182 | print("%8d %8d %8d %8d %12.0f %10.0f" % |
| 183 | (total, misses, hits, mbd, buff, cached)) |
unixtest | 57abe5b | 2016-01-31 10:47:03 +0000 | [diff] [blame] | 184 | |
| 185 | mpa = 0 |
| 186 | mbd = 0 |
| 187 | apcl = 0 |
| 188 | apd = 0 |
Joel Fernandes | 2b34870 | 2018-02-27 20:38:42 -0800 | [diff] [blame] | 189 | total = 0 |
unixtest | 57abe5b | 2016-01-31 10:47:03 +0000 | [diff] [blame] | 190 | misses = 0 |
Joel Fernandes | 2b34870 | 2018-02-27 20:38:42 -0800 | [diff] [blame] | 191 | hits = 0 |
unixtest | 57abe5b | 2016-01-31 10:47:03 +0000 | [diff] [blame] | 192 | cached = 0 |
| 193 | buff = 0 |
unixtest | 57abe5b | 2016-01-31 10:47:03 +0000 | [diff] [blame] | 194 | |
| 195 | if exiting: |
| 196 | print("Detaching...") |
| 197 | exit() |