These modules all end in the extension .ph and are searched for first in the directory collectl is being executed from and then /usr/share/collectl. If the module name is prepended with a directory name, collectl will search only there.
The reason you might care about this is that now if you want to produce your own exportable form of output and be able to print it locally, make it available to another program over a socket or even write to a local file while still being able to log to raw and/or plot formats, you get that all that functionality for free.
NOTE: sexpr only supports d, f, h and s | |
avg|max|min | used in conjunction with i=, send the average, maximum or minimum of the data over the associated set of intervals specified by i=. If neither avg, min or max is used, the values from the most recent monitoring interval will be reported. |
co | this does not take a value and indicates changes only such that only data elements that have changed since they were last sampled are reported in an attempt to minimize processing and network bandwidth. If not specified, samples for all reporting intervals will be sent. |
d=mask | debugging mask, see beginning of the actual export file for details |
f=file | names the output snapshot file, which applies to only lexpr and sexpr.
If this option is not used, -f must be and the snapshot file names are then set to the
single character L and S respectively and written into the directory
associated with -f
|
h | shows help/usage |
i=secs | specifies the reporting interval in seconds. In other words, if you specify i=60, a sample will be reported every 60 seconds independent of collectl's monitoring interval. The default is to report every sample. This interval must be a multiple of the base collectl interval. |
s | specifies a subset of those subsystems specified with -s in the collectl command line and only data collected for that subset will be reported. The default to report everything. |
ttl | is the time to live in intervals for each piece of performance data. If more than this number of intervals passes data will be sent regardless of whether it changed or not and the ttl countdown timer reset. The default is 5. This actually has a second use for gexpr and that is to set the gmond ttl to double this number multiplied by the interval. |
Logging
Collectl can actually create up to 3 different type of log files and it's worth spending a little more
time enumerating how collectl decides where and when to create them.
This first section gets called almost immediately by collectl after reading in the various user switches. This is the place to catch switch errors and since this routine always requires -scm we'll just hardcode it to that and reject any user entered ones. This initialization subroutine must be named for our module followed by Init.
sub vmstatInit { error("-s not allowed with 'vmstat'") if $userSubsys ne ''; error("-f requires either --rawtoo or -P") if $filename ne '' && !$rawtooFlag && !$plotFlag; error("-P or --rawtoo require -f") if $filename eq '' && ($rawtooFlag || $plotFlag); $subsys=$userSubsys='cm'; }
The if statement uses collectl's standard idiom for printing headers based on the number of lines printed and whether or not the user wants only a single header, no header or even to clear the screen between headers. If you do not want/need all these features it's perfectly fine to use a more simplified header printing mechanism, such as the one is sexpr.ph.
sub vmstat { my $line; if (printHeader()) { $line= "${cls}#${miniBlanks}procs ---------------memory (KB)--------------- --swaps-- -----io---- --system-- ----cpu-----\n"; $line.="#$miniDateTime r b swpd free buff cache inact active si so bi bo in cs us sy id wa\n"; }
my $datetime=''; if ($options=~/[dDTm]/) { ($ss, $mm, $hh, $mday, $mon, $year)=localtime($lastSecs); $datetime=sprintf("%02d:%02d:%02d", $hh, $mm, $ss); $datetime=sprintf("%02d/%02d %s", $mon+1, $mday, $datetime) if $options=~/d/; $datetime=sprintf("%04d%02d%02d %s", $year+1900, $mon+1, $mday, $datetime) if $options=~/D/; $datetime.=".$usecs" if ($options=~/m/); $datetime.=" "; }
my $i=$NumCpus; my $usr=$userP[$i]+$niceP[$i]; my $sys=$sysP[$i]+$irqP[$i]+$softP[$i]+$stealP[$i]; $line.=sprintf("%s %2d %2d %6s %6s %6s %6s %6s %6s %4d %4d %5d %5d %4d %5d %2d %2d %3d %2d\n", $datetime, $procsRun, $procsBlock, cvt($swapUsed,6,1,1), cvt($memFree,6,1,1), cvt($memBuf,6,1,1), cvt($memCached,6,1,1), cvt($inactive,6,1,1), cvt($active,6,1,1), $swapin/$intSecs, $swapout/$intSecs, $pagein/$intSecs, $pageout/$intSecs, $intrpt/$intSecs, $ctxt/$intSecs, $usr, $sys, $idleP[$i], $waitP[$i]);
printText($line); } 1;
updated Jan 03, 2012 |