[ale] "real-time" (was Linux job)

[James P. Kinney III]

On Wed, 2006-03-29 at 11:12 -0500, Pete Hardie wrote:
> Re: "Realtime"
> 
> A number of jobs ago, I worked at a company using the Cadre software
> tools suite, whihc had a FSM tool with hooks for "realtime" events. 
> The manual for that tool had a cute story:
> 
> It seems that several sfotware engineers were discussing realtime
> event processing, and each was subtly bragging about the speed of
> their system.  The one engineer piped up that she was working on the
> system that provided telemetry for the atomic bomb tests, where the
> bomb was suspended in a subterranean hole at one end of a 100m beam,
> and the telemetry equipment was at the other end.  Since the explosion
> vaporized things as it hit them, the telemetry equipment had to get
> its signals up the wire ahead of the blast, which included the EM
> pulse.
> 
> That won the night.

That's "hard real time"!  A friend of mine works with a similar hard
real time process on the D0 project at Fermi Lab. Every 20 seconds, the
experiment chamber (an area the volume of a mid-sized house filled with
detectors) gets a 1 second proton beam burst into the target chamber.
That produces detectable electrical signals that produce a digital data
set on the order of 25TB. My friends PhD was on the first stage filter
that sifted this down to _only_ 800-1000GB in less than 8 seconds. This
is then passed to a flotilla of systems that do second and then third
order sorting to extract the final 60-80GB of real experimental data.
That is then piped to the tape drive wall for archival. Yes, that's a
10'x40' wall of LTO drives running full speed.

Every 20 seconds this process repeats as long as the beam stays with in
parameters.

The magnetic fields are so strong that monitors last about a week near
the magnetic control chambers. All cabling is triple shielded coax
because of the electric fields. Static shocks are common even with
conductive outer wear.

> 
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-- 
James P. Kinney III          \Changing the mobile computing world/
CEO & Director of Engineering \          one Linux user         /
Local Net Solutions,LLC        \           at a time.          /
770-493-8244                    \.___________________________./
http://www.localnetsolutions.com

GPG ID: 829C6CA7 James P. Kinney III (M.S. Physics)
<jkinney at localnetsolutions.com>
Fingerprint = 3C9E 6366 54FC A3FE BA4D 0659 6190 ADC3 829C 6CA7
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