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Full Discussion: semaphore access speed
Top Forums Programming semaphore access speed Post 302243868 by ramen_noodle on Monday 6th of October 2008 05:51:47 PM
Old 10-06-2008
Just for contrast on a modern intel SMP processor running linux 2.6.18 I get more
than a million operations/sec.
On that basis I don't believe this qualifies as a bug..more of a growing pain.
Linux has always been a project in forward motion. You either catch up or suffer.
Linus is short on apologies for this model that I've seen.
Code:
1402465.14 semop/s (5000000/3565151)
1409187.85 semop/s (5000000/3548143)
1448182.72 semop/s (5000000/3452603)

On a FreeBSD 6.0 machine (uniprocessor) the time is interesting...
Intel(R) Celeron(R) CPU 2.00GHz (1999.94-MHz 686-class CPU)
Code:
501281.02 semop/s (5000000/9974445)
500868.00 semop/s (5000000/9982670)
450727.95 semop/s (5000000/11093166)


Last edited by ramen_noodle; 10-08-2008 at 02:43 PM.. Reason: typo on kernel version
 

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cdde.xml(5)															       cdde.xml(5)

NAME
cdde.xml - Configuration file for cdde DESCRIPTION
When cdde is run for the first time, an example xml configuration file (~/.cdde.xml) is created for you: <?xml version="1.0"?> <cdde delay="5000000"> <drive path="/dev/cdrom"> <audio command="echo An audio cd was inserted."/> <data command="echo A data cd was inserted."/> <dvd command="echo A dvd was inserted."/> <vcd command="echo A vcd was inserted."/> <svcd command="echo A svcd was inserted."/> <blank command="echo A blank cdr/dvdr was inserted."/> <mixed command="echo A mixed (audio/data) cd was inserted."/> </drive> </cdde> This default file is not very useful, and so I suggest you to edit it to your needs before running cdde again. You may add as many drive entries, or commands as you like. If multiple entries are found for a type of disc then all entries will be run in the order they are found. The specific device in use can be passed to the command with one of the following special tags: %dev% - is replaced with the device name of the cdrom that just had a disc inserted %mnt% - is replaced with the listed mount point for the cdrom that just had a disc inserted Note: %mnt% is determined through your fstab (usually located in /etc) file. If you do not have a listing for each <drive> in the fstab this will cause problems. This way, you can tell your video player which device to use when playing a VCD, for example. EXAMPLE
This is an example of ~/.cdde.xml file: <?xml version="1.0"?> <cdde delay="5000000"> <drive path="/dev/cdroms/cdrom0"/> <audio command="xmms %mnt%"/> <data command="mount %mnt%"/> <dvd command="xterm -iconic -e mplayer -fs -xineramascreen 1 -dvd 1"/> <vcd command="xterm -iconic -e mplayer -fs -xineramascreen 1 -vcd 1"/> <svcd command="xterm -iconic -e mplayer -fs -xineramascreen 1 -vcd 1"/> <blank command="gcombust"/> <mixed command="mount %mnt%"/> </drive> </cdde> FILES
~/.cdde.xml SEE ALSO
cdde(1) AUTHORS
Eric Lathrop <eric@ericlathrop.com> Stanislav Maslovski <stanislav.maslovski@gmail.com> WEBSITE
For the latest release of cdde, see: http://cdde.sourceforge.net/ Eric Lathrop 0.3.1 cdde.xml(5)
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