Crashing When Closing a Connection

[BrettRToomey]

Hello,

I have been experiencing a crash in my scripts while using the Oracle.jl package. I managed to minimise the code and generate this recreation:

julia> include("db.jl");

julia> c = Oracle.Connection(db_user, db_pass, db)
Oracle.Connection(Oracle.Context(Ptr{Nothing} @0x00007ffc4044c250), Ptr{Nothing} @0x00007ffc407053e0, Oracle.EncodingInfo("UTF-8", 4, "UTF-8", 4), nothing)

julia> Oracle.close(c)

julia> c = Oracle.Connection(db_user, db_pass, db)
Oracle.Connection(Oracle.Context(Ptr{Nothing} @0x00007ffc407096f0), Ptr{Nothing} @0x00007ffc40707320, Oracle.EncodingInfo("UTF-8", 4, "UTF-8", 4), nothing)

julia> Oracle.close(c)
zsh: segmentation fault  julia

db.jl only has db credentials and the db string, that way I don't risk leaking them.

I am on macOS Big Sur with an Intel-based MacBook. I am using Julia 1.6.1. Please ask if there is anything else you need from me!

[felipenoris]

@BrettRToomey can you downgrade to Oracle.jl v0.2.0 and repeat the test?

[BrettRToomey]

I tried that with the minimised sample and I can't seem to recreate the crash

[BrettRToomey]

And the original script doesn't crash either @felipenoris

[felipenoris]

I guess you're hitting oracle/odpi#156 .
The quick fix is to create a single Context for your application and use this connection constructor.

A better solution is to use a Oracle.Pool and create connections from the pool. It can be made thread-safe if you use create_mode=Oracle.ORA_MODE_CREATE_THREADED.

[BrettRToomey]

I was planning to move to pools soon anyway, so it's nice to see that they get around this issue. Is there any way I can help? Although it seems like everything is done, we are just waiting on a new odpi release?

[felipenoris]

@BrettRToomey please, check if this is solved in the master branch.

[cjbj]

@felipenoris this is just a passing FYI. With ODPI-C 4.2 sessions pools are always created in threaded mode. See https://oracle.github.io/odpi/doc/releasenotes.html#version-4-2-may-18-2021

[felipenoris]

@cjbj thanks for the info!

[BrettRToomey]

@felipenoris master branch has fixed the crash. Thanks!