Mnesia tables: load times and sizes after deletion

Bruce Fitzsimons <>
Mon Aug 18 11:15:24 CEST 2003


Hi Ulf,

> Are you sure the tables were created under R9B?
> If so, are you sure they are dets files (.DAT when using
> mnesia)?

Ahhh....no they are disk logs, as you said.

> Granted, I've been on a long vacation and my brain may not
> have engaged fully yet, but I recall that disc_copies are
> stored on disk in disk_log format (mnesia gives them the
> extension .DCD), and not as dets files. Disc_only copies
> are stored as dets files.

Your brain is fine. I wasn't aware that the options had such a dramatic
difference in implementation. Its is good to know.

> The file size should adjust at every log dump,
> and a load time of minutes seems a bit slow, perhaps, but
> I wouldn't want to swear that it's abnormal.

How can I force a log dump? Do they happen periodically under Mnesia or do I
need to initiate a backup or something? I've never seen the internals of
Mnesia documented to this extent (although whenever I say this it is
immediately pointed out in the place I've been looking...).

Thanks for the help.

/Bruce





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