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World: r3wp

[!REBOL3]

BrianH
20-May-2011
[8776]
This code might be a better test: repeat i to-integer #7fffffffffffffff 
[if zero? i // 1'000'000 [recycle] to-hex i]

It should have less memory usage overall and if words are recycled 
then it won't run out. I'll run it now.
Geomol
20-May-2011
[8777]
Where are the words coming into the picture?
BrianH
20-May-2011
[8778]
TO-HEX generates an issue!, which is a word type in R3. Yes, you 
can even bind them.
Geomol
20-May-2011
[8779]
Spooky! :)
BrianH
20-May-2011
[8780]
I figure that not creating the temporary string, and running recycle 
every once in a while, might make the memory problems go away. So 
far the R3 process is staying at exactly the same memory, less than 
a gig. I also tossed an assignment in there so I can know which number 
it fails on.
Andreas
20-May-2011
[8781x4]
the jump from ~900M to ~1.2G took ages
then another aeon fuer 1.2G to 1.4G
and hours for 1.4G to 1.7G and fail
(jfyi)
BrianH
20-May-2011
[8785]
The time on mine won't be comparable because it's only running on 
one of 4 cores, and the others will be mildly occupied.
Andreas
20-May-2011
[8786]
R3 won't utilise more than 1 core either way :)
BrianH
20-May-2011
[8787x2]
Of course :)
Ooo, tasks! But error handling is still broken in tasks, so this 
test won't work :(
Andreas
20-May-2011
[8789x3]
Ah, here's the jump :)
From 1.0G to 1.9G, after 14m cpu time
But it's still running
BrianH
20-May-2011
[8792x2]
Mine just jumped up a hundred megs, still running :)
It failed a lot earlier for me (some time in the last half hour), 
never getting over 1.2GB, and now there isn't enough memory to figure 
out what the number it failed at was. Looks like you run out of memory 
before you run into the word limit, and that the symbol table isn't 
cleaned up by the recycler. Good to know.
onetom
21-May-2011
[8794]
these experiments remind me how painful was it to figure out why 
are we getting those funky out of memory messages, saying something 
about PermGen in java
Geomol
21-May-2011
[8795x2]
The internal symbol table is there to make symbols work at all.


I don't think, I understand this fully. To me, it's like needing 
an internal string table to make strings work. Or an internal integer 
table to make integers work. Why not just have contexts, and don't 
put words in any context, if the word is just data? And if a word 
go from being data to hold more meaning (have a value attached), 
then put it in a context.
If you take a book written in finnish, you see a lot of words, but 
they have no meaning to you. When you close the book, the finnish 
words shouldn't take up any space in your brain.
Gabriele
21-May-2011
[8797]
Geomol, I think you are confusing design with implementation. The 
implementation can be improved; however, it's a compromise between 
the complexity of it and how common your "millions of words" scenario 
is in practice.
Geomol
21-May-2011
[8798]
Makes sense.
Kaj
21-May-2011
[8799x4]
Putting words in a context

 is binding. That's very different from the symbol table, which you 
 could say "binds" symbol strings to integer IDs
If you can't read Finnish, it means the Finnish symbols are not bound 
to values in contexts in your head. Closing the book and erasing 
the symbol table is equivalent to quitting the REBOL proces, which 
does release the memory
I'm sure some Finnish words are also words in Danish, so forgetting 
the symbol table wouldn't help your situation :-)
I'm sure because my name is one of them...
Pekr
21-May-2011
[8803]
I prefer Finnish Vodka, and Finnish music :-)
Ladislav
21-May-2011
[8804]
John, you are missing some things others know and find obvious. For 
example, do you know the answer to the following question?

    What is the ratio between

        stringn: func [n] [head insert/dup copy "" #"a" n]


        word: to word! stringn 1 t1: time-block [equal? word word] 0,05

        word: to word! stringn 1000 t2: time-block [equal? word word] 0,05
        t2 / t1

compared to


        string: stringn 1 t1: time-block [equal? string string] 0,05

        string: stringn 1000 t2: time-block [equal? string string] 0,05
        t2 / t1
?
onetom
21-May-2011
[8805x2]
time-block? u mean delta-time?
(your naming is more intuitive though... it's also 'time in bash...)
Geomol
21-May-2011
[8807x2]
Thanks, Ladislav. Good examples!


The thing, I missed, was that REBOL has this extra internal data 
structure to hold symbols (words), I though, just the contexts was 
used for that. So comparing words (that are not bound to any context) 
are much faster than comparing strings in REBOL. I see different 
possibilities, depending on implementation. If a word is changed 
to the result from a hash calculation, then two different words might 
give the same result, right? It's unlikely, but it could happen. 
That's why map datastructures are combined with lists, when two different 
hash calculations give same result. The other possibility is, that 
words are changed to pointers pointing to their entry in the map 
(hash table). Do you know, what of the two, REBOL implement? In other 
words, could two different words be equal in REBOL?


About the strings, then it's possible to do kind of the same with 
hashing. Lua does that. If you have two different but identical strings 
(same string content) in Lua, they share the same memory area. Hashing 
is involved, and I guess, comparing string would be equal fast as 
comparing words, if REBOL did the same. (unless words are exchanged 
with the result from the hash calculation, but then two words might 
be equal)
After a little testing, it seems, words are changed to a hash result, 
and REBOL gives an error, if two different words give same result:

>> s: "abcdefghijklmn"

>> forever [if equal? a: to word! random s b: to word! random s [print 
[a b]]]
** Internal Error: No more global variable space

The error comes really fast.
Kaj
21-May-2011
[8809]
Petr, Nightwish? :-)
Geomol
21-May-2011
[8810x3]
Above test is in R2.
R3 keeps going and can't be stopped with <Esc>.
<Esc> + <Ctrl>-c seem to stop it.
Kaj
21-May-2011
[8813x2]
Global variable space should be the special object holding global 
values in R2. That's not the symbol table, either
My guess is that it must do more useless binding than R3
Geomol
21-May-2011
[8815]
You're right. to word! put it in system/words, I need to do to block!, 
I guess.
Kaj
21-May-2011
[8816]
Maybe to-lit-word works
Geomol
21-May-2011
[8817]
In R2:

s: "abcdefghijklmn"

forever [if equal? a: to block! random s b: to block! random s [print 
[a b]]]

rebol-console: line 2:  5658 Floating point exception./rebol --noviewtop

A crash. Interesting! :)
Kaj
21-May-2011
[8818]
Indeed
Geomol
21-May-2011
[8819]
to lit-words! also put it in system/words in R2.
Kaj
21-May-2011
[8820x2]
That's probably one of the things optimised away in R3
It's such a shame it's stalled
onetom
21-May-2011
[8822]
I think, Carl will return soon and he will open source R3.

He must have a hard time doing that other job, but probably he will 
experience the bright side of the open collaboration too.

Im expecting him to realize that he can actually help the world effectively 
if he can unleash the power us, the long time fans of rebol.
Kaj
21-May-2011
[8823x2]
Don't hold your breath
John, to keep your mind on the edge of the cliff, did you know about 
the global series table? :-)
Geomol
21-May-2011
[8825]
Not sure, what's that?