Skip to content

gh-185 Add protection for closed env #186

New issue

Have a question about this project? Sign up for a free GitHub account to open an issue and contact its maintainers and the community.

Sign up for GitHub

By clicking “Sign up for GitHub”, you agree to our terms of service and privacy statement. We’ll occasionally send you account related emails.

Already on GitHub? Sign in to your account

Jump to bottom
Closed
at055612 wants to merge 4 commits into from
Closed

gh-185 Add protection for closed env #186

at055612 wants to merge 4 commits into from

Conversation

@at055612
Copy link
Collaborator

@at055612 at055612 commented Nov 4, 2021 •
edited
Loading

Fixes #185

  • Change Cursor and Txn to hold the Env instance so it can be checked for its open/closed state.
  • Add calls to env.checkNotClosed() in methods that call out to the LMDB lib to prevent the JVM crashing if the env has been closed.
  • Add lots of tests involving env closure.

Happy to re-work this if you disagree with the approach or see problems with it.

@at055612
lmdbjavagh-185 Add protection for closed env
3da5b06 
Change Cursor and Txn to hold the Env instance so it can be checked
for its open/closed state.
Add calls to env.checkNotClosed() in methods that call out to the LMDB
lib to prevent the JVM crashing if the env has been closed.
Add lots of tests involving env closure.
@at055612
lmdbjavagh-185 Add env.checkNotClosed to Dbi.put
303c9c0
@at055612
lmdbjavagh-185 Remove redundant test
1bc841e
@at055612
lmdbjavagh-185 Remove unused imports
46e41ff
@at055612
Copy link
Collaborator Author

at055612 commented Nov 4, 2021

@benalexau If I run the test classes in isolation they work fine but when run via mvn test I see

# A fatal error has been detected by the Java Runtime Environment:
#
#  SIGSEGV (0xb) at pc=0x00007f4ec41f6a15, pid=22462, tid=22468
#
# JRE version: OpenJDK Runtime Environment (15.0.2+7) (build 15.0.2+7-27)
# Java VM: OpenJDK 64-Bit Server VM (15.0.2+7-27, mixed mode, sharing, tiered, compressed oops, g1 gc, linux-amd64)
# Problematic frame:
# C  [libpthread.so.0+0x9a15]  __pthread_mutex_lock_full+0x335

My suspicion (with zero c knowledge) is that the various tests that are closing the env while txns/cursors/dbis are open are leaving things (i.e. mutex locks) in an untidy state that are then causing later tests to fail. Does this seem right and is there any way to get around this?

An alternative approach would be for the Env to keep a track of open txns/cursors and either prevent closure of the env if any are open or force closure of the open txns/cursors. Such an approach would add overhead though.

@at055612 at055612 mentioned this pull request Nov 5, 2021
Closed
@benalexau benalexau force-pushed the master branch 2 times, most recently from 0a78414 to a1162e1 Compare December 10, 2022 01:29
benalexau added a commit that referenced this pull request Feb 3, 2023
@benalexau
Add protection for closed env (#186)
3db0def
@benalexau
Copy link
Member

benalexau commented Feb 3, 2023

Thanks @at055612 for this PR and my apologies for the delay in reviewing it. I have merged your changes via commit 3db0def. I added a Maven Surefire configuration to avoid reusing the forked test processes and that overcame the error.

@benalexau benalexau closed this Feb 3, 2023
Sign up for free to join this conversation on GitHub. Already have an account? Sign in to comment

Reviewers

No reviews

Assignees

No one assigned

Labels

None yet

Projects

None yet

Milestone

No milestone

Development

Successfully merging this pull request may close these issues.

SIGSEGV on cursorIterable.next() when the env is closed

2 participants

@at055612 @benalexau