Thanks for pointing me to the concept of nodes (had never heard of them before.. as an LMDB user for years I haven't had the need be aware of this internal manual until now).

Out of curiosity, what were the reasons for the design decision of using a 2-byte alignment?

Regards,
Sam


Oct 13, 2023, 19:26 by hyc@symas.com:
Sam Dave wrote:
Hello,

I have two LMDB databases, identical except one has key size 34 bytes and the other key size 33 bytes. (Both have same value sizes and same number of pairs).

How can the file sizes on disk be exactly the same? Is this because of the 2-byte alignment mentioned here? https://github.com/AltSysrq/lmdb-zero/issues/8

I wonder if this 2-byte alignment was documented anywhere.

RTFM.

http://www.lmdb.tech/doc/group__internal.html

Search for "align"


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-- Howard Chu
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Director, Highland Sun http://highlandsun.com/hyc/
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