Tim Uckun wrote:

The language is Crystal which is still a very young language. It does not have threading at this time so there should be no issues with mutexes. While writing the code I never opened up a database but did repeatedly open up the environment and if the app ran into an error while coding didn't properly close the environment.

I didn't ask about languages, I asked about OS and LMDB version.

LMDB uses mutexes internally to serialize write transactions.

Howard while I have you on the line....

The documentation says to be very careful about closing databases and says it's not normally necessary. I am going to omit those calls from my wrapper. Is this OK? I will probably omit a bunch of other calls too at least from the first release but I want to make sure I don't omit anything crucial.

Probably a good idea to omit dbi_close.

Thanks.

On Tue, Nov 22, 2016 at 7:42 AM, Howard Chu <hyc@symas.com mailto:hyc@symas.com> wrote:

Tim Uckun wrote:

    Hi All.

    I am writing a wrapper for Lmdb for the Crystal language.  During the
    process
    of writing my code started hanging when attempting to open a
    transaction.  At
    first I thought I was calling the C functions wrong but it turned out
    to be
    some sort of a corruption in the database itself. I deleted the database
    directory and the code started working fine again.


Sounds like you're not using robust mutexes. Just a guess, since you
didn't provide any info about your OS / platform or LMDB version.

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