Does a LMDB database file ever shrink, after row deletion, if so when?

[Tinker]

Content preview: Hi! Is there any mechanism in LMDB to give back disk space
after some particular amount of row deletion, how does this work, if not
are there any plans for it now? If there's not, as a user I need 2x disk space
and some mechanism to be able to migrate, so automatic shrinking would be
a great thing. [...]

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Hi!

Is there any mechanism in LMDB to give back disk space after some
particular amount of row deletion, how does this work, if not are there
any plans for it now?

If there's not, as a user I need 2x disk space and some mechanism to be
able to migrate, so automatic shrinking would be a great thing.

Thanks!!
Tinker

[Howard Chu]

Content preview: Tinker wrote: > Hi! > > Is there any mechanism in LMDB to
give back disk space after some particular > amount of row deletion, how does
this work, if not are there any plans for it > now? No. LMDB keeps all space
and reuses it for future write operations. [...]

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[69.43.206.106 listed in list.dnswl.org]
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[score: 0.0000]

Hi!
Is there any mechanism in LMDB to give back disk space after some particular
amount of row deletion, how does this work, if not are there any plans for it
now?

No. LMDB keeps all space and reuses it for future write operations.

If there's not, as a user I need 2x disk space and some mechanism to be able
to migrate, so automatic shrinking would be a great thing.

There's nothing automatic but you can use mdb_env_copy() to implement your own
strategy.