mirror_zfs/cmd/arcstat/arcstat
Ryan Moeller 4f342e45be Canonicalize Python shebangs
/usr/bin/env python3 is the suggested[1] shebang for Python in general
(likewise for python2) and is conventional across platforms. This eases
development on systems where python is not installed in /usr/bin
(FreeBSD for example) and makes it possible to develop in virtual
environments (venv) for isolating dependencies.

Many packaging guidelines discourage the use of /usr/bin/env, but since
this is the canonical way of writing shebangs in the Python community,
many packaging scripts are already equipped to handle substituting the
appropriate absolute path to python automatically.

Some RPM package builders lacking brp-mangle-shebangs need a small
fallback mechanism in the package spec to stamp the appropriate shebang
on installed Python scripts.

[1]: https://docs.python.org/3/using/unix.html?#miscellaneous

Reviewed-by: Richard Laager <rlaager@wiktel.com>
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Reviewed-by: George Melikov <mail@gmelikov.ru>
Signed-off-by: Ryan Moeller <ryan@ixsystems.com>
Closes #9314
2019-09-12 13:32:32 -07:00

471 lines
13 KiB
Python
Executable File

#!/usr/bin/env python3
#
# Print out ZFS ARC Statistics exported via kstat(1)
# For a definition of fields, or usage, use arctstat.pl -v
#
# This script is a fork of the original arcstat.pl (0.1) by
# Neelakanth Nadgir, originally published on his Sun blog on
# 09/18/2007
# http://blogs.sun.com/realneel/entry/zfs_arc_statistics
#
# This version aims to improve upon the original by adding features
# and fixing bugs as needed. This version is maintained by
# Mike Harsch and is hosted in a public open source repository:
# http://github.com/mharsch/arcstat
#
# Comments, Questions, or Suggestions are always welcome.
# Contact the maintainer at ( mike at harschsystems dot com )
#
# CDDL HEADER START
#
# The contents of this file are subject to the terms of the
# Common Development and Distribution License, Version 1.0 only
# (the "License"). You may not use this file except in compliance
# with the License.
#
# You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
# or http://www.opensolaris.org/os/licensing.
# See the License for the specific language governing permissions
# and limitations under the License.
#
# When distributing Covered Code, include this CDDL HEADER in each
# file and include the License file at usr/src/OPENSOLARIS.LICENSE.
# If applicable, add the following below this CDDL HEADER, with the
# fields enclosed by brackets "[]" replaced with your own identifying
# information: Portions Copyright [yyyy] [name of copyright owner]
#
# CDDL HEADER END
#
#
# Fields have a fixed width. Every interval, we fill the "v"
# hash with its corresponding value (v[field]=value) using calculate().
# @hdr is the array of fields that needs to be printed, so we
# just iterate over this array and print the values using our pretty printer.
#
# This script must remain compatible with Python 2.6+ and Python 3.4+.
#
import sys
import time
import getopt
import re
import copy
from decimal import Decimal
from signal import signal, SIGINT, SIGWINCH, SIG_DFL
cols = {
# HDR: [Size, Scale, Description]
"time": [8, -1, "Time"],
"hits": [4, 1000, "ARC reads per second"],
"miss": [4, 1000, "ARC misses per second"],
"read": [4, 1000, "Total ARC accesses per second"],
"hit%": [4, 100, "ARC Hit percentage"],
"miss%": [5, 100, "ARC miss percentage"],
"dhit": [4, 1000, "Demand hits per second"],
"dmis": [4, 1000, "Demand misses per second"],
"dh%": [3, 100, "Demand hit percentage"],
"dm%": [3, 100, "Demand miss percentage"],
"phit": [4, 1000, "Prefetch hits per second"],
"pmis": [4, 1000, "Prefetch misses per second"],
"ph%": [3, 100, "Prefetch hits percentage"],
"pm%": [3, 100, "Prefetch miss percentage"],
"mhit": [4, 1000, "Metadata hits per second"],
"mmis": [4, 1000, "Metadata misses per second"],
"mread": [5, 1000, "Metadata accesses per second"],
"mh%": [3, 100, "Metadata hit percentage"],
"mm%": [3, 100, "Metadata miss percentage"],
"arcsz": [5, 1024, "ARC Size"],
"c": [4, 1024, "ARC Target Size"],
"mfu": [4, 1000, "MFU List hits per second"],
"mru": [4, 1000, "MRU List hits per second"],
"mfug": [4, 1000, "MFU Ghost List hits per second"],
"mrug": [4, 1000, "MRU Ghost List hits per second"],
"eskip": [5, 1000, "evict_skip per second"],
"mtxmis": [6, 1000, "mutex_miss per second"],
"dread": [5, 1000, "Demand accesses per second"],
"pread": [5, 1000, "Prefetch accesses per second"],
"l2hits": [6, 1000, "L2ARC hits per second"],
"l2miss": [6, 1000, "L2ARC misses per second"],
"l2read": [6, 1000, "Total L2ARC accesses per second"],
"l2hit%": [6, 100, "L2ARC access hit percentage"],
"l2miss%": [7, 100, "L2ARC access miss percentage"],
"l2asize": [7, 1024, "Actual (compressed) size of the L2ARC"],
"l2size": [6, 1024, "Size of the L2ARC"],
"l2bytes": [7, 1024, "bytes read per second from the L2ARC"],
"grow": [4, 1000, "ARC Grow disabled"],
"need": [4, 1024, "ARC Reclaim need"],
"free": [4, 1024, "ARC Free memory"],
}
v = {}
hdr = ["time", "read", "miss", "miss%", "dmis", "dm%", "pmis", "pm%", "mmis",
"mm%", "arcsz", "c"]
xhdr = ["time", "mfu", "mru", "mfug", "mrug", "eskip", "mtxmis", "dread",
"pread", "read"]
sint = 1 # Default interval is 1 second
count = 1 # Default count is 1
hdr_intr = 20 # Print header every 20 lines of output
opfile = None
sep = " " # Default separator is 2 spaces
version = "0.4"
l2exist = False
cmd = ("Usage: arcstat [-hvx] [-f fields] [-o file] [-s string] [interval "
"[count]]\n")
cur = {}
d = {}
out = None
kstat = None
def detailed_usage():
sys.stderr.write("%s\n" % cmd)
sys.stderr.write("Field definitions are as follows:\n")
for key in cols:
sys.stderr.write("%11s : %s\n" % (key, cols[key][2]))
sys.stderr.write("\n")
sys.exit(0)
def usage():
sys.stderr.write("%s\n" % cmd)
sys.stderr.write("\t -h : Print this help message\n")
sys.stderr.write("\t -v : List all possible field headers and definitions"
"\n")
sys.stderr.write("\t -x : Print extended stats\n")
sys.stderr.write("\t -f : Specify specific fields to print (see -v)\n")
sys.stderr.write("\t -o : Redirect output to the specified file\n")
sys.stderr.write("\t -s : Override default field separator with custom "
"character or string\n")
sys.stderr.write("\nExamples:\n")
sys.stderr.write("\tarcstat -o /tmp/a.log 2 10\n")
sys.stderr.write("\tarcstat -s \",\" -o /tmp/a.log 2 10\n")
sys.stderr.write("\tarcstat -v\n")
sys.stderr.write("\tarcstat -f time,hit%,dh%,ph%,mh% 1\n")
sys.stderr.write("\n")
sys.exit(1)
def kstat_update():
global kstat
k = [line.strip() for line in open('/proc/spl/kstat/zfs/arcstats')]
if not k:
sys.exit(1)
del k[0:2]
kstat = {}
for s in k:
if not s:
continue
name, unused, value = s.split()
kstat[name] = Decimal(value)
def snap_stats():
global cur
global kstat
prev = copy.deepcopy(cur)
kstat_update()
cur = kstat
for key in cur:
if re.match(key, "class"):
continue
if key in prev:
d[key] = cur[key] - prev[key]
else:
d[key] = cur[key]
def prettynum(sz, scale, num=0):
suffix = [' ', 'K', 'M', 'G', 'T', 'P', 'E', 'Z']
index = 0
save = 0
# Special case for date field
if scale == -1:
return "%s" % num
# Rounding error, return 0
elif 0 < num < 1:
num = 0
while num > scale and index < 5:
save = num
num = num / scale
index += 1
if index == 0:
return "%*d" % (sz, num)
if (save / scale) < 10:
return "%*.1f%s" % (sz - 1, num, suffix[index])
else:
return "%*d%s" % (sz - 1, num, suffix[index])
def print_values():
global hdr
global sep
global v
for col in hdr:
sys.stdout.write("%s%s" % (
prettynum(cols[col][0], cols[col][1], v[col]),
sep
))
sys.stdout.write("\n")
sys.stdout.flush()
def print_header():
global hdr
global sep
for col in hdr:
sys.stdout.write("%*s%s" % (cols[col][0], col, sep))
sys.stdout.write("\n")
def get_terminal_lines():
try:
import fcntl
import termios
import struct
data = fcntl.ioctl(sys.stdout.fileno(), termios.TIOCGWINSZ, '1234')
sz = struct.unpack('hh', data)
return sz[0]
except Exception:
pass
def update_hdr_intr():
global hdr_intr
lines = get_terminal_lines()
if lines and lines > 3:
hdr_intr = lines - 3
def resize_handler(signum, frame):
update_hdr_intr()
def init():
global sint
global count
global hdr
global xhdr
global opfile
global sep
global out
global l2exist
desired_cols = None
xflag = False
hflag = False
vflag = False
i = 1
try:
opts, args = getopt.getopt(
sys.argv[1:],
"xo:hvs:f:",
[
"extended",
"outfile",
"help",
"verbose",
"separator",
"columns"
]
)
except getopt.error as msg:
sys.stderr.write("Error: %s\n" % str(msg))
usage()
opts = None
for opt, arg in opts:
if opt in ('-x', '--extended'):
xflag = True
if opt in ('-o', '--outfile'):
opfile = arg
i += 1
if opt in ('-h', '--help'):
hflag = True
if opt in ('-v', '--verbose'):
vflag = True
if opt in ('-s', '--separator'):
sep = arg
i += 1
if opt in ('-f', '--columns'):
desired_cols = arg
i += 1
i += 1
argv = sys.argv[i:]
sint = Decimal(argv[0]) if argv else sint
count = int(argv[1]) if len(argv) > 1 else count
if len(argv) > 1:
sint = Decimal(argv[0])
count = int(argv[1])
elif len(argv) > 0:
sint = Decimal(argv[0])
count = 0
if hflag or (xflag and desired_cols):
usage()
if vflag:
detailed_usage()
if xflag:
hdr = xhdr
update_hdr_intr()
# check if L2ARC exists
snap_stats()
l2_size = cur.get("l2_size")
if l2_size:
l2exist = True
if desired_cols:
hdr = desired_cols.split(",")
invalid = []
incompat = []
for ele in hdr:
if ele not in cols:
invalid.append(ele)
elif not l2exist and ele.startswith("l2"):
sys.stdout.write("No L2ARC Here\n%s\n" % ele)
incompat.append(ele)
if len(invalid) > 0:
sys.stderr.write("Invalid column definition! -- %s\n" % invalid)
usage()
if len(incompat) > 0:
sys.stderr.write("Incompatible field specified! -- %s\n" %
incompat)
usage()
if opfile:
try:
out = open(opfile, "w")
sys.stdout = out
except IOError:
sys.stderr.write("Cannot open %s for writing\n" % opfile)
sys.exit(1)
def calculate():
global d
global v
global l2exist
v = dict()
v["time"] = time.strftime("%H:%M:%S", time.localtime())
v["hits"] = d["hits"] / sint
v["miss"] = d["misses"] / sint
v["read"] = v["hits"] + v["miss"]
v["hit%"] = 100 * v["hits"] / v["read"] if v["read"] > 0 else 0
v["miss%"] = 100 - v["hit%"] if v["read"] > 0 else 0
v["dhit"] = (d["demand_data_hits"] + d["demand_metadata_hits"]) / sint
v["dmis"] = (d["demand_data_misses"] + d["demand_metadata_misses"]) / sint
v["dread"] = v["dhit"] + v["dmis"]
v["dh%"] = 100 * v["dhit"] / v["dread"] if v["dread"] > 0 else 0
v["dm%"] = 100 - v["dh%"] if v["dread"] > 0 else 0
v["phit"] = (d["prefetch_data_hits"] + d["prefetch_metadata_hits"]) / sint
v["pmis"] = (d["prefetch_data_misses"] +
d["prefetch_metadata_misses"]) / sint
v["pread"] = v["phit"] + v["pmis"]
v["ph%"] = 100 * v["phit"] / v["pread"] if v["pread"] > 0 else 0
v["pm%"] = 100 - v["ph%"] if v["pread"] > 0 else 0
v["mhit"] = (d["prefetch_metadata_hits"] +
d["demand_metadata_hits"]) / sint
v["mmis"] = (d["prefetch_metadata_misses"] +
d["demand_metadata_misses"]) / sint
v["mread"] = v["mhit"] + v["mmis"]
v["mh%"] = 100 * v["mhit"] / v["mread"] if v["mread"] > 0 else 0
v["mm%"] = 100 - v["mh%"] if v["mread"] > 0 else 0
v["arcsz"] = cur["size"]
v["c"] = cur["c"]
v["mfu"] = d["mfu_hits"] / sint
v["mru"] = d["mru_hits"] / sint
v["mrug"] = d["mru_ghost_hits"] / sint
v["mfug"] = d["mfu_ghost_hits"] / sint
v["eskip"] = d["evict_skip"] / sint
v["mtxmis"] = d["mutex_miss"] / sint
if l2exist:
v["l2hits"] = d["l2_hits"] / sint
v["l2miss"] = d["l2_misses"] / sint
v["l2read"] = v["l2hits"] + v["l2miss"]
v["l2hit%"] = 100 * v["l2hits"] / v["l2read"] if v["l2read"] > 0 else 0
v["l2miss%"] = 100 - v["l2hit%"] if v["l2read"] > 0 else 0
v["l2asize"] = cur["l2_asize"]
v["l2size"] = cur["l2_size"]
v["l2bytes"] = d["l2_read_bytes"] / sint
v["grow"] = 0 if cur["arc_no_grow"] else 1
v["need"] = cur["arc_need_free"]
v["free"] = cur["arc_sys_free"]
def main():
global sint
global count
global hdr_intr
i = 0
count_flag = 0
init()
if count > 0:
count_flag = 1
signal(SIGINT, SIG_DFL)
signal(SIGWINCH, resize_handler)
while True:
if i == 0:
print_header()
snap_stats()
calculate()
print_values()
if count_flag == 1:
if count <= 1:
break
count -= 1
i = 0 if i >= hdr_intr else i + 1
time.sleep(sint)
if out:
out.close()
if __name__ == '__main__':
main()