"everybody in the control room is using Java"

"everybody in the control room is using Java"

[Hyman Rosen]

<http://news.com.com/2100-1007_3-5142220.html?tag=nefd_top>

Re: "everybody in the control room is using Java"

[Martin Dowie]

"Hyman Rosen" <hyrosen@mail.com> wrote in message
news:1074275354.853176@master.nyc.kbcfp.com...
> <http://news.com.com/2100-1007_3-5142220.html?tag=nefd_top>

Yeah, not the real thing though!..

http://www.ghs.com/news/230811j.html

Re: "everybody in the control room is using Java"

[Preben Randhol]

On 2004-01-16, Martin Dowie <martin.dowie@btopenworld.com> wrote:
> "Hyman Rosen" <hyrosen@mail.com> wrote in message
> news:1074275354.853176@master.nyc.kbcfp.com...
>> <http://news.com.com/2100-1007_3-5142220.html?tag=nefd_top>
>
> Yeah, not the real thing though!..
>
> http://www.ghs.com/news/230811j.html

Does Green Hills use Ada here or they use Java or something else?

Preben
-- 
"Saving keystrokes is the job of the text editor, not the programming
 language."

Re: "everybody in the control room is using Java"

[Martin Dowie]

"Preben Randhol" <randhol+valid_for_reply_from_news@pvv.org> wrote in
message
news:slrnc0i9a4.69b.randhol+valid_for_reply_from_news@k-083152.nt.ntnu.no...
> On 2004-01-16, Martin Dowie <martin.dowie@btopenworld.com> wrote:
> > "Hyman Rosen" <hyrosen@mail.com> wrote in message
> > news:1074275354.853176@master.nyc.kbcfp.com...
> >> <http://news.com.com/2100-1007_3-5142220.html?tag=nefd_top>
> >
> > Yeah, not the real thing though!..
> >
> > http://www.ghs.com/news/230811j.html
>
> Does Green Hills use Ada here or they use Java or something else?

They seem to have a fairly consistent rule that if a project uses Ada then
they mention both "MULTI" and "AdaMULTI" in the press release, in
the 'about GHS' section. If it doesn't use Ada then they don't mention it
and just mention "MULTI".

In this press release they mention both.

Shame there is no word from Beagle 2 - it uses a version of GNAT.
Although, from what I understand, Ada is the defacto language for all
ESA projects, so the "Mars Express" craft that got it there is still working
perfectly well.

Re: "everybody in the control room is using Java"

[Dmytry Lavrov]

"Martin Dowie" <martin.dowie@btopenworld.com> wrote in message news:<bu9o60$h6v$1@sparta.btinternet.com>...
> "Hyman Rosen" <hyrosen@mail.com> wrote in message
> news:1074275354.853176@master.nyc.kbcfp.com...
> > <http://news.com.com/2100-1007_3-5142220.html?tag=nefd_top>
> 
> Yeah, not the real thing though!..
> 
> http://www.ghs.com/news/230811j.html

http://www.cobalt.com/aboutsun/media/features/mars.html

http://www.linuxdevices.com/news/NS3674252711.html

Interesting thing, that so called "java technology" ."It's  powers the
rover from earth" :)

Major problem in mars missions is probably programs portability and
execution with as much as possible limited access to hardware(no
access to things like ports,legs,cameras,trusters,fans,etc) ,like java
applets on my PC where i don't want it to have any access to my
hardware except framebuffer memory ?

Question:

I just can't believe _at_all_ that realtime java will _always_ meet
deadline,expecially that someone has proved that.

Should be assumed that worsest possible GC(garbage collection)
operations could happen between deadlines.That's mean,i think,normally
load of processor should be not more than several precents,because
processor should be fast enough to do GC.If there's JIT like
compiler,situation are even worse,it's should be assumed that all
commands are interpreted,not compiled! Or someone should do very
pricely analysis.... and it's possible that there will be something
wrong with it itself,so it's should be checked....

Program should use not more than,say, 1/100th of time(assuming that GC
lag 100 times more pricely than normal allocation,and that lag could
happen constantly  ),and run at <1/20 speed(interpretation)....damn
inefficient ,because it's better to have slower and more reliable
processors than ,hehe,p4 . Is there any tools for SPECIFIC java
platform that will calculate maximal execution time _accurately_? It's
should be very hard to make that tool that it will not assume GC lags
always like i'm doing.

Also,there's no doubling for software if there's same runtime in both
rovers.

Re: "everybody in the control room is using Java"

[Vinzent 'Gadget' Hoefler]

Dmytry Lavrov wrote:

>Should be assumed that worsest possible GC(garbage collection)
>operations could happen between deadlines.

IIRC, in RTJ you can turn off and/or call the GC explicitely.
Also, there is a concept of so-called immortal memory that is by
definition excluded from any GC-algorithms (because it exists
"forever") and the NoHeapRealtimeThread classes are allowed to
interrupt any on-going garbage collection.


Vinzent.

Re: "everybody in the control room is using Java"

[Ole-Hjalmar Kristensen]

>>>>> "DL" == Dmytry Lavrov <dmytrylavrov@fsmail.net> writes:

    DL> "Martin Dowie" <martin.dowie@btopenworld.com> wrote in message news:<bu9o60$h6v$1@sparta.btinternet.com>...
    >> "Hyman Rosen" <hyrosen@mail.com> wrote in message
    >> news:1074275354.853176@master.nyc.kbcfp.com...
    >> > <http://news.com.com/2100-1007_3-5142220.html?tag=nefd_top>
    >> 
    >> Yeah, not the real thing though!..
    >> 
    >> http://www.ghs.com/news/230811j.html

    DL> http://www.cobalt.com/aboutsun/media/features/mars.html

    DL> http://www.linuxdevices.com/news/NS3674252711.html

    DL> Interesting thing, that so called "java technology" ."It's  powers the
    DL> rover from earth" :)

    DL> Major problem in mars missions is probably programs portability and
    DL> execution with as much as possible limited access to hardware(no
    DL> access to things like ports,legs,cameras,trusters,fans,etc) ,like java
    DL> applets on my PC where i don't want it to have any access to my
    DL> hardware except framebuffer memory ?

    DL> Question:

    DL> I just can't believe _at_all_ that realtime java will _always_ meet
    DL> deadline,expecially that someone has proved that.

    DL> Should be assumed that worsest possible GC(garbage collection)
    DL> operations could happen between deadlines.That's mean,i think,normally
    DL> load of processor should be not more than several precents,because
    DL> processor should be fast enough to do GC.If there's JIT like
    DL> compiler,situation are even worse,it's should be assumed that all
    DL> commands are interpreted,not compiled! Or someone should do very
    DL> pricely analysis.... and it's possible that there will be something
    DL> wrong with it itself,so it's should be checked....

Don't know about the compiler, but real time garbage collection is
essentially a solved problem, provided you do not allocate such large
objects that the time to move a single object breaks your schedule.
Look in the book "Garbage Collection" by Lin and Jones, or do a Google
serach for Henry G. Baker (who now is a venture capitalist it seems) 
to read his papers. 

    DL> Program should use not more than,say, 1/100th of time(assuming that GC
    DL> lag 100 times more pricely than normal allocation,and that lag could
    DL> happen constantly  ),and run at <1/20 speed(interpretation)....damn
    DL> inefficient ,because it's better to have slower and more reliable
    DL> processors than ,hehe,p4 . Is there any tools for SPECIFIC java
    DL> platform that will calculate maximal execution time _accurately_? It's
    DL> should be very hard to make that tool that it will not assume GC lags
    DL> always like i'm doing.

    DL> Also,there's no doubling for software if there's same runtime in both
    DL> rovers.

-- 
   C++: The power, elegance and simplicity of a hand grenade.

Re: "everybody in the control room is using Java"

[Erlo Haugen]

On 17 Jan 2004 06:58:06 -0800
dmytrylavrov@fsmail.net (Dmytry Lavrov) wrote:

> "Martin Dowie" <martin.dowie@btopenworld.com> wrote in message
> news:<bu9o60$h6v$1@sparta.btinternet.com>...
> > "Hyman Rosen" <hyrosen@mail.com> wrote in message
> > news:1074275354.853176@master.nyc.kbcfp.com...
> > > <http://news.com.com/2100-1007_3-5142220.html?tag=nefd_top>
> > 
> > Yeah, not the real thing though!..
> > 
> > http://www.ghs.com/news/230811j.html
> 
> http://www.cobalt.com/aboutsun/media/features/mars.html
> 
> http://www.linuxdevices.com/news/NS3674252711.html
> 
> Interesting thing, that so called "java technology" ."It's  powers the
> rover from earth" :)

This is from the cobalt-link above:

Q:What exactly is Java's role in the Mars Rover mission?

A: The places where NASA scientists have used Java for this mission is all on
the ground side right now.

It seems to me that Java is not used in the vehicle, or am I mistaken here?

-- 
Erlo
Remove the underscores
Sorry, I don't have time for this. I've got bugs to write.

Re: "everybody in the control room is using Java"

[Preben Randhol]

On 2004-01-19, Erlo Haugen <_elh_@_terma_._com_> wrote:
> This is from the cobalt-link above:
>
> Q:What exactly is Java's role in the Mars Rover mission?
>
> A: The places where NASA scientists have used Java for this mission is all on
> the ground side right now.
>
> It seems to me that Java is not used in the vehicle, or am I mistaken here?

No, you are not.


-- 
"Saving keystrokes is the job of the text editor, not the programming
 language."