The question is "Magma could be used in a real-world application?"
I think not.
I used Magma a couple of years ago. I had to migrate 13000 records from a
database, build objects form the data and find duplications. The whole
process of migration to Magma took more than two weaks. Yes, weaks!. 15
days!. And I had to made a lot of strange things to reduce time. I made
periodical cleaning up process in the middle of the whole migation  to
improve performance. The first attemps tend to infinite, I reduce it to two
weaks.
The application was in production two years, with a lot of performance
problems. Finally we have to throw it away.
Now I'm trying again. Now I use very simple objects (just a couple of string
variables) with only one index for one of this strings .
But the problem is once again the same: each time I add an object to a
MagmaCollection I have to look after duplicates, and if found, merge them.
I'm adding object to 4 MagmaCollections, with an index with size 64. (I need
more, but once again, performance...)
Look at this numbers
I tried with 2000 records (total is 76000).
If I just add the objects without search it takes 2 minutes
If I search the objects it takes 16 minutes!
If I search the objects, and then iterate the results to make a more fine
comparision, it takes 20 minutes!

In a linear progression, total time for 76000 records would be 12 hours,
which is not very good. But time doesn't grow lineary but exponentially.
I tried with 12000 records: 5 hours 30 minutes. How must I supose it will
take with 76000 records. 2 days?  3?
These are not times for a process I surely will perform again as my model
grows.
The numbers tells, once again, that the problem is not adding the objects,
merging or materializing them but  searching on a MagmaCollection. Time goes
by and this problem is not solved.

I'm desperate.
I have no way of persist my objects if I want to avoid everybody laughing at
me.

Norberto

On Thu, Oct 21, 2010 at 3:33 AM, Igor Stasenko <siguctua at gmail.com> wrote:

> Hello all,
> sorry for cross-posting. :)
>
> I'd like to ask you, if anyone could share either an image or
> installation with application,
> which using Magma OODB.
> I'd like to use it & test how changing different aspects of Magma
> internals could affect the performance.
>
> There's many tricks, which is known by Chris how to speed it up by
> cleverly fine-tuning various Magma options,
> like read strategy etc.
> But what i'd like is to see, is some setup, used by people, and by
> taking it, see how it could make run faster,
> without changing an application code.
>
> I remember, someone gave a talk @ ESUG, that they were using Magma for
> their application,
> but then forced to switch to another DB layer, because they had bad
> performance issues.
> It would be good, if you could give me the code, so i can run it and
> see if things could be improved.
> Its not a problem, if code is not open-source, we could sign an NDA,
> if this is necessary.
>
> I need something real, simply because benchmarks sometimes not
> representative. :)
>
> --
> Best regards,
> Igor Stasenko AKA sig.
>
>


-- 
Norberto Manzanos
Instituto de Investigaciones en Humanidades y Ciencias Sociales (IdIHCS)
FaHCE/UNLP - CONICET
Calle 48 e/ 6 y 7 s/Nº - 8º piso - oficina 803
Tel: +54-221-4230125 interno 262
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