[KPhotoAlbum] Performance problem with nested categories
Robert L Krawitz
rlk at alum.mit.edu
Sat Dec 9 02:16:40 CET 2006
From: "Jesper K. Pedersen" <blackie at blackie.dk>
Date: Sat, 9 Dec 2006 01:43:20 +0100
Why do you think hasCategoryInfo is expensive? It looks up an item in a map
O(logn) plus afterwards look another item up in a set (another map to be
technical), which is another O(logn).
It's probably not that expensive in and of itself (although it isn't
constant time, either); the problem is that it's being called so many
On Friday 08 December 2006 23:20, Robert L Krawitz wrote:
| I have a database with about 17000 photos in it.
| If I select the folder "20d" (which has subfolders such as dcim,
| dcim/100canon, etc.), it takes a very long time -- maybe 30 seconds or
| thereabouts. Selecting a leaf folder is very quick.
| I put some trace code in. It looks like the implementation of
| DB::OptionValueMatcher::eval() and its children (in particular,
| ImageInfo::hasCategoryInfo) is very slow. The trace I got looks
| something like this:
Robert Krawitz <rlk at alum.mit.edu>
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