Mnesia tables: load times and sizes after deletion

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Mnesia tables: load times and sizes after deletion

Bruce Fitzsimons-2

I've just been playing with my little jukebox I wrote for broadcasting
background music in Erlang. It logs the songs played into an mnesia table
'playlog' (set, disc_copies).

I managed to get 71,000 entries into the table, at which point it took a
number of minutes to open on my little Duron 1300 w/ ATA100 hd

I used a (inefficient) mnemosyne query to get all the entries older than 1
day and delete them, and this worked. Surprisingly fast, to mnemosynes

What did surprise me is that the on-disk size, and the size reported by
mnesia:table_info(playlog, size) continued to increased (it was still

Is this normal? The docs say size = total number of records, is it actually
max size? Even after the delete and normal shutdown the table did not shrink
in either sense. It still took a number of minutes to open too.

I guess I'm just curious to know if this is normal?

I attempted to directly open the mnesia files under dets to query them...but
that is apparently not allowed. A good thing probably.

Thanks for any info. I've deleted and recreated the table now. This is all
under R9C (nice work guys, great docs), although the DB was created using