[KPhotoAlbum] 45 000 images & KPhotoAlbum speed on Athlon 1GHz

[Robert L Krawitz]

   Date: Tue, 31 Jan 2006 00:06:55 +0200
   From: "Risto H. Kurppa" <risto at kurppa.fi>

   Just to let you know what happens with a large database..

   I finally managed to load (ie. I was able to track the damaged
   jpegs) my photo collection into KimDaBa (using
   kimdaba-2006-01-14-noi18n ).

Try 2006-01-28.

   Sometimes it's very fast and does right away what I'm asking it to
   do (a search, show thumbnails, whatever). But sometimes (with no
   other resource monster programs running) it gets 'stuck'. It starts
   to work on something and doesn't respond to anything. I see that
   it's reading or writing (reading, I hope..) the hard drive. Usually
   the program takes some 370 (VM) + 200 (PM) Mb of memory - but it's
   been up to 700 + something.. But it'll eventually start working, if
   I'll just let it work (over the night, for example..) long enoug.

   At least saving makes it stuck for a while.. Never actually measured
   it precisely but I'd guess up to an hour or something

   Database size is about 21 Mb ( not compressed).
   Processor is Athlon 1GHz

How much physical memory (which is likely to be much more important
here than the processor speed)?  What you're describing sounds a lot
like disk thrashing.  My guess would be that it doesn't have very good
memory locality, which is common with database type things, and you've
simply exceeded your physical memory.  When that happens, performance
falls off a cliff -- random memory access is about 100,000x faster
than random disk access.

I'm going to guess here that you have 512 MB of RAM, figuring that
your X server and everything else you have takes a few hundred MB of
virtual memory, leaving a couple hundred left over for KPhotoAlbum.
If that's the case, upgrading to 1 GB might solve your problem
instantly.  If you only have 256 MB, then you really are going to
thrash it badly.

   Then some actual questions:
   -Does anyone else have similar problems with large (how large?) database?

Mine's about 5 MB (11000~12000 images), and I have no problems of this
nature.  Then again, the laptop I use (a somewhat homebrew Dell
Latitude C840 aka Inspiron 8200) has 1.5 GB, so for all intents and
purposes it simply doesn't page to disk.