forked from iovisor/bcc
-
Notifications
You must be signed in to change notification settings - Fork 0
/
biotop.py
executable file
·213 lines (182 loc) · 5.46 KB
/
biotop.py
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
#!/usr/bin/python
# @lint-avoid-python-3-compatibility-imports
#
# biotop block device (disk) I/O by process.
# For Linux, uses BCC, eBPF.
#
# USAGE: biotop.py [-h] [-C] [-r MAXROWS] [interval] [count]
#
# This uses in-kernel eBPF maps to cache process details (PID and comm) by I/O
# request, as well as a starting timestamp for calculating I/O latency.
#
# Copyright 2016 Netflix, Inc.
# Licensed under the Apache License, Version 2.0 (the "License")
#
# 06-Feb-2016 Brendan Gregg Created this.
from __future__ import print_function
from bcc import BPF
from time import sleep, strftime
import argparse
import signal
from subprocess import call
# arguments
examples = """examples:
./biotop # block device I/O top, 1 second refresh
./biotop -C # don't clear the screen
./biotop 5 # 5 second summaries
./biotop 5 10 # 5 second summaries, 10 times only
"""
parser = argparse.ArgumentParser(
description="Block device (disk) I/O by process",
formatter_class=argparse.RawDescriptionHelpFormatter,
epilog=examples)
parser.add_argument("-C", "--noclear", action="store_true",
help="don't clear the screen")
parser.add_argument("-r", "--maxrows", default=20,
help="maximum rows to print, default 20")
parser.add_argument("interval", nargs="?", default=1,
help="output interval, in seconds")
parser.add_argument("count", nargs="?", default=99999999,
help="number of outputs")
args = parser.parse_args()
interval = int(args.interval)
countdown = int(args.count)
maxrows = int(args.maxrows)
clear = not int(args.noclear)
# linux stats
loadavg = "/proc/loadavg"
diskstats = "/proc/diskstats"
# signal handler
def signal_ignore(signal, frame):
print()
# load BPF program
b = BPF(text="""
#include <uapi/linux/ptrace.h>
#include <linux/blkdev.h>
// for saving process info by request
struct who_t {
u32 pid;
char name[TASK_COMM_LEN];
};
// the key for the output summary
struct info_t {
u32 pid;
int type;
int major;
int minor;
char name[TASK_COMM_LEN];
};
// the value of the output summary
struct val_t {
u64 bytes;
u64 us;
u32 io;
};
BPF_HASH(start, struct request *);
BPF_HASH(whobyreq, struct request *, struct who_t);
BPF_HASH(counts, struct info_t, struct val_t);
// cache PID and comm by-req
int trace_pid_start(struct pt_regs *ctx, struct request *req)
{
struct who_t who = {};
if (bpf_get_current_comm(&who.name, sizeof(who.name)) == 0) {
who.pid = bpf_get_current_pid_tgid();
whobyreq.update(&req, &who);
}
return 0;
}
// time block I/O
int trace_req_start(struct pt_regs *ctx, struct request *req)
{
u64 ts;
ts = bpf_ktime_get_ns();
start.update(&req, &ts);
return 0;
}
// output
int trace_req_completion(struct pt_regs *ctx, struct request *req)
{
u64 *tsp;
// fetch timestamp and calculate delta
tsp = start.lookup(&req);
if (tsp == 0) {
return 0; // missed tracing issue
}
struct who_t *whop;
struct val_t *valp, zero = {};
u64 delta_us = (bpf_ktime_get_ns() - *tsp) / 1000;
// setup info_t key
struct info_t info = {};
info.major = req->rq_disk->major;
info.minor = req->rq_disk->first_minor;
info.type = req->cmd_flags & REQ_WRITE;
whop = whobyreq.lookup(&req);
if (whop == 0) {
// missed pid who, save stats as pid 0
valp = counts.lookup_or_init(&info, &zero);
} else {
info.pid = whop->pid;
__builtin_memcpy(&info.name, whop->name, sizeof(info.name));
valp = counts.lookup_or_init(&info, &zero);
}
// save stats
valp->us += delta_us;
valp->bytes += req->__data_len;
valp->io++;
start.delete(&req);
whobyreq.delete(&req);
return 0;
}
""", debug=0)
b.attach_kprobe(event="blk_account_io_start", fn_name="trace_pid_start")
b.attach_kprobe(event="blk_start_request", fn_name="trace_req_start")
b.attach_kprobe(event="blk_mq_start_request", fn_name="trace_req_start")
b.attach_kprobe(event="blk_account_io_completion",
fn_name="trace_req_completion")
print('Tracing... Output every %d secs. Hit Ctrl-C to end' % interval)
# cache disk major,minor -> diskname
disklookup = {}
with open(diskstats) as stats:
for line in stats:
a = line.split()
disklookup[a[0] + "," + a[1]] = a[2]
# output
exiting = 0
while 1:
try:
sleep(interval)
except KeyboardInterrupt:
exiting = 1
# header
if clear:
call("clear")
else:
print()
with open(loadavg) as stats:
print("%-8s loadavg: %s" % (strftime("%H:%M:%S"), stats.read()))
print("%-6s %-16s %1s %-3s %-3s %-8s %5s %7s %6s" % ("PID", "COMM",
"D", "MAJ", "MIN", "DISK", "I/O", "Kbytes", "AVGms"))
# by-PID output
counts = b.get_table("counts")
line = 0
for k, v in reversed(sorted(counts.items(),
key=lambda counts: counts[1].bytes)):
# lookup disk
disk = str(k.major) + "," + str(k.minor)
if disk in disklookup:
diskname = disklookup[disk]
else:
diskname = "?"
# print line
avg_ms = (float(v.us) / 1000) / v.io
print("%-6d %-16s %1s %-3d %-3d %-8s %5s %7s %6.2f" % (k.pid, k.name,
"W" if k.type else "R", k.major, k.minor, diskname, v.io,
v.bytes / 1024, avg_ms))
line += 1
if line >= maxrows:
break
counts.clear()
countdown -= 1
if exiting or countdown == 0:
print("Detaching...")
exit()