Weblog Home Web site's Home Clip art Search Clker.com – Available downloads RSS

Recent Posts:

arrow image github a valuable opensource too...
arrow image Easy chrome extension to convert...
arrow image Updated svg edit - much better p...
arrow image Professional graphics designers:...
arrow image Refresh when drawing
arrow image That's impressive
arrow image Another quick feature added
arrow image Image editor now works on Intern...
arrow image Manually tracing cliparts out of...
arrow image Draw edit the SVG images online
arrow image Where to find good old public do...
arrow image Developing clip arts using old p...
arrow image Expected downtime tonight
arrow image Automatic vectorization is up an...
arrow image Ubuntu lucid lynx is extremely s...
arrow image Integrating the tracer
arrow image Automatic vectorization, coming ...
arrow image Updated clker interface
arrow image using ubuntu as my main desktop ...
arrow image Full time on clker
arrow image Clker will be down tonight
arrow image Tracing local and lineart images
arrow image Bad HD - clker will be down on S...
arrow image Updates to profiles
arrow image Crayon video - Marathon runner
arrow image A detailed tutorial on Crayon
arrow image Crayon image resources & tutoria...
arrow image Example tracing president obama
arrow image More on Crayon
arrow image First version of the online trac...
arrow image Now you can edit your uploads
arrow image Clipart tracer: New feature comi...
arrow image Apache hanging once in a while -...
arrow image Injuries from working on compute...
arrow image Restarting the server once in a ...
arrow image Writing my own webserver
arrow image Flex - Zooming in on large bitma...
arrow image Linux average load
arrow image Caching SQL with PHP
arrow image Wordpress plugin version 1.2 rel...
arrow image Fixing vote up/vote down icons
arrow image Google native client
arrow image New wordpress, looks great
arrow image Bug reports and feature requests...
arrow image Further flex testing
arrow image Some flex ideas
arrow image actionscript mode for emacs
arrow image Linux spirits crawling in chrome
arrow image Wordpress clip art plugin
arrow image Adding Clker.com to opera search...


Sites I like:
Arabic movie database

Linux average load

It was the first time yesterday that I took sometime to understand what is the “average load” that appears with the top shell command. It turns out that it is a very informative number, if used right.

Linux averages the number of processes running, or can run – but may be blocked waiting for I/O. The average is calculated three times: for a minute, 5 minutes and 15 minutes.

In case that no processes were blocked on I/O, this number should always be less than the number of available CPU cores. For insance, if the load average is 2.6 this means that in average 2.6 processes were running or wanted to run. If you have only two cores, this means that there’s in average 0.6 processes that cannot find an available CPU to run, which means that you need to upgrade your machine (or server).

Since this number grows when processes are blocked on I/O, it is nice to know whether there’s any blocked on I/O or not before going ahead and spending the last penny to buy new hardrware. The solution is a tool called atop. If the disks are stressed and cannot keep up with the requests (and consequently processes will be waiting for the disk) you will see the DSK line (or lines if you had more than one) in red.

At that point you should find who is the culprit, and do something to run that process in a better way.


Leave a Reply


Fatal error: Call to undefined function akismet_counter() in /home/webs/www.clker.com/blog/wp-content/themes/mibrahim/footer.php on line 27