memory usage


#1

As my collection has grown, mp3tag takes much longer to load, export, import tags, doubling the number of files has meant a lot more than twice the time taken. There are likely causes for slowness:

  1. changing ID1 to ID2 tags, which requires a file rewrite if I change things, but I discount that as I know for sure all my files already have ID2 tags.
  2. disk speed and disk caching. I think I occasionally see this because sometimes mp3tag (and the disk system) seem to pause for a minute or so.
  3. windows memory handling. When I run Task Manager, I see mp3tag using 800 meg of memory. This is on a machine with only 1 Gig of memory, so windows is using virtual memory extensively. And I've seen Task Manager reporting approx 2 Gig page file use (my machine has max virtual memory 2.5 Gb). I have had an mp3tag message saying 'out of memory' when trying to export, followed by a program crash. I think this is the main cause of slowness when I try to load 50000 files or more!

mp3tag works very fast with 2000-10000 tracks loaded, works very slowly with 50000 tracks, and is almost guaranteed to stop working when 75000 tracks are loaded.

The answer is to load less files at any one time, but my question is how many? Can anyone (programming team?) explain mp3tag's memory use? Looks to me that it creates in-memory data structures when files are loaded or as tags are exported. I'm looking for a rule or thumb for how much memory is required for each task, per 1000 tracks? Then I can choose the number of files depending on which machine I'm on and how much memory is free, knowing in advance I'm unlikely to end up in difficulties.

Happy Christmas to all.

Derek


#2

I am afraid there isn't one that would be accurate enough to really help.
In general: mp3tag is (still) a 32bit application. So it is limited to the 3GB barrier as is Windows 32bit.
As long as you have enough electrical storage (RAM) and Windows does not have to get into the paging mode and move chunks of the RAM to the hard disk (which only has roughly a tenth of the access speed as RAM has) the speed should be in straight relation to the amount of tracks being loaded.
The amount of data being used per track depends highly on the actual length of the tag data. If you have added lengthy comments, subtitles, lyrics and big cover pictures you will be able to load far less tracks than someone who only fills artist and title tags.
In general you are about right with some 50000 tracks - some have reported 70000 in this forum. But it is not the number of tracks but the extent of data in the tags.


#3

You might want to rethink how you're using Mp3tag. I find the need to load my entire library in Mp3tag to be extremely rare. I may do it once every year or two. Typically I work on one album at a time and occasionally one artist. It's important that the library is organized into artist/album folders so that you can use Windows Explorer's context menu to launch Mp3tag with just an album or artist folder loaded.

Once an album is fully tagged, which is always done after ripping the CD, there are only a couple of scenarios where it needs to be retagged. Most often it'ts to fix a typo, correct a date, or change a genre. All of those are done by loading either the album or the artist. The only reason to load the whole library is add or remove tags on all or a significant number of files.