#!/usr/bin/sh # # dnlcstat - DNLC statistics. # Written in DTrace (Solaris 10 3/05). # # The DNLC is the Directory Name Lookup Cache. Filename lookups often # return a hit from here, before needing to traverse the regular file # system cache or go to disk. # # $Id: dnlcstat,v 1.1.1.1 2015/09/30 22:01:07 christos Exp $ # # USAGE: dnlcstat [interval [count]] # # FIELDS: # # %hit hit percentage for this sample # hit number of DNLC hits in this sample # miss number of DNLC misses in this sample # # SEE ALSO: CacheKit, http://www.brendangregg.com/cachekit.html # (contains a dnlcstat written in Perl, which uses less CPU) # # COPYRIGHT: Copyright (c) 2005 Brendan Gregg. # # 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 Docs/cddl1.txt # or http://www.opensolaris.org/os/licensing. # See the License for the specific language governing permissions # and limitations under the License. # # CDDL HEADER END # # 27-Mar-2004 Brendan Gregg Created this. # 14-Jun-2005 " " Updated style. # 14-Jun-2005 " " Last update. # ############################## # --- Process Arguments --- # ### default values interval=1; count=-1 ### check arguments if [ "$1" = "-h" -o "$1" = "--help" ]; then cat <<-END >&2 USAGE: dnlcstat [interval [count]] dnlcstat # 1 second samples, infinite eg, dnlcstat 1 # print every 1 second dnlcstat 5 6 # print every 5 seconds, 6 times END exit 1 fi ### argument logic if [ "$1" -gt 0 ]; then interval=$1; count=-1; shift fi if [ "$1" -gt 0 ]; then count=$1; shift fi if [ $interval -eq 0 ]; then interval=1 fi ################################# # --- Main Program, DTrace --- # /usr/sbin/dtrace -n ' #pragma D option quiet /* * Command line arguments */ inline int INTERVAL = '$interval'; inline int COUNTER = '$count'; inline int SCREEN = 21; int hits; /* hits */ int misses; /* misses */ /* * Initialise variables */ dtrace:::BEGIN { lines = SCREEN + 1; counts = COUNTER; secs = INTERVAL; first = 1; } /* * Print header */ dtrace:::BEGIN, tick-1sec /first || (secs == 0 && lines > SCREEN)/ { printf("%10s %8s %8s\n","dnlc %hit","hit","miss"); lines = 0; first = 0; } /* * Probe DNLC lookups */ fbt:genunix:dnlc_lookup:return { hits += arg1 == 0 ? 0 : 1; misses += arg1 == 0 ? 1 : 0; } profile:::tick-1sec { secs--; } /* * Print output line */ profile:::tick-1sec /secs == 0/ { /* calculate hit percent */ this->divide = misses + hits == 0 ? 1 : misses + hits; ratio = hits * 100 / this->divide; /* print output */ printf("%10d %8d %8d\n",ratio,hits,misses); /* clear counters */ hits = 0; misses = 0; /* process counts */ secs = INTERVAL; counts--; lines++; } /* * End */ profile:::tick-1sec /counts == 0/ { exit(0); } '