mirror_zfs/cmd/arcstat/arcstat.py
Brian Behlendorf d738d34da5 Add dbufstat.py command
The dbufstat.py command was added to provide a conveniant way to
easily determine what ZFS is caching.  The script consumes the
raw /proc/spl/kstat/zfs/dbufs kstat data can consolidates it in
to a more human readable form.  This was designed primarily as
a tool to aid developers but it may also be useful for advanced
users who want more visibility in to what the ARC is caching.

When run without options dbufstat.py will default to showing a
list of all objects with at least one buffer present in the
cache.  The total cache space consumed by that object will be
printed on the right along with the object type.  Similar to the
arcstats.py command the -x option may used to display additional
fields.

Two other modes of operation are also supported by dbufstat.py
and the expectation is additional display modes may be added as
needed.  The -t option will summerize the total number of bytes
cached for each object type, and the -b option will show every
dbuf currently cached.

The script was designed to be consistent with arcstat.py and
includes most of the same options and funcationality.

Signed-off-by: Prakash Surya <surya1@llnl.gov>
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
2013-10-25 14:52:45 -07:00

441 lines
12 KiB
Python
Executable File

#!/usr/bin/python
#
# 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.
#
import sys
import time
import getopt
import re
import copy
from decimal import Decimal
from signal import signal, SIGINT
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 Data hits per second"],
"dmis": [4, 1000, "Demand Data misses per second"],
"dh%": [3, 100, "Demand Data hit percentage"],
"dm%": [3, 100, "Demand Data 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": [4, 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"],
"rmis": [4, 1000, "recycle_miss per second"],
"dread": [5, 1000, "Demand data 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"],
"l2size": [6, 1024, "Size of the L2ARC"],
"l2bytes": [7, 1024, "bytes read per second from the L2ARC"],
}
v = {}
hdr = ["time", "read", "miss", "miss%", "dmis", "dm%", "pmis", "pm%", "mmis",
"mm%", "arcsz", "c"]
xhdr = ["time", "mfu", "mru", "mfug", "mrug", "eskip", "mtxmis", "rmis",
"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.py [-hvx] [-f fields] [-o file] [-s string] [interval "
"[count]]\n")
cur = {}
d = {}
out = None
kstat = None
float_pobj = re.compile("^[0-9]+(\.[0-9]+)?$")
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(1)
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.py -o /tmp/a.log 2 10\n")
sys.stderr.write("\tarcstat.py -s \",\" -o /tmp/a.log 2 10\n")
sys.stderr.write("\tarcstat.py -v\n")
sys.stderr.write("\tarcstat.py -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 num > 0 and 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")
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 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",
"seperator",
"columns"
]
)
except getopt.error, msg:
sys.stderr.write(msg)
usage()
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', '--seperator'):
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
# 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:
sys.stderr.write("Cannot open %s for writing\n" % opfile)
sys.exit(1)
def calculate():
global d
global v
global l2exist
v = {}
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["rmis"] = d["recycle_miss"] / 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["l2size"] = cur["l2_size"]
v["l2bytes"] = d["l2_read_bytes"] / sint
def sighandler(*args):
sys.exit(0)
def main():
global sint
global count
global hdr_intr
i = 0
count_flag = 0
init()
if count > 0:
count_flag = 1
signal(SIGINT, sighandler)
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()