Reserved memory usage for facial recognition

Gilles Caulier caulier.gilles at
Sun Jul 12 10:14:36 BST 2020

Hi Nghia,

The amount memory available on host system is detected at startup by
DImg using code from core/libs/kmemoryinfo/

You must remember this code, as we have used it in my office last
winter -:=)))...

You said that 700ms is slow. How did you evaluate this state ? Did you
compare with other algorithm ?

Did you compile the code without debug symbols and with G++
optimizations (there is just one CMake configuration flag to switch
for that)



Le dim. 12 juil. 2020 à 10:51, Maik Qualmann <metzpinguin at> a écrit :
> We reserve memory for the DImg cache, depending on the existing one, up to
> 200MB.
> fileio/loadingcache.cpp#L169
> So around 200MB for the face engine, if they are still securely in the system,
> I would find okay for current computers with around 8GB of memory.
> But SQLite is quite fast, did you set the parameter to activate the SQLite
> cache?
> Maik
> Am Sonntag, 12. Juli 2020, 08:27:22 CEST schrieb Nghia Duong:
> > Hi all,
> >
> > I am testing a spatial database implementation on SQLite for facial
> > recognition of faces engine. For now, we can perform K-Nearest search on a
> > table but I am concerned about its performance. For a table of 16000
> > entries, the search time is about 700ms and it's a little bit slow.
> > Therefore, I am considering storing a KD-Tree structure directly on memory.
> > I estimate that the memory needed for a data node is from 512 bytes to 1500
> > bytes, both on memory and on the database.
> >
> > I don't know whether it is too much. Could you let me know the amount of
> > memory that can be reserved for this part of faces engine, please? Thank
> > you in advance.

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