Issue
I'm writing a messaging app as my final project for 12 grade and I have an error that I have no idea how to even approach. I disabled and re-enabled features of the web app one by one to see when the error occurs, and I observed that when I try to bring the active conversations that one user has, my server crashes. This doesn't happen constantly, it seems like random occurrences. Here is the error message by the server:
#
# A fatal error has been detected by the Java Runtime Environment:
#
# EXCEPTION_ACCESS_VIOLATION (0xc0000005) at pc=0x000000007034537d, pid=13536, tid=9944
#
# JRE version: Java(TM) SE Runtime Environment 18.9 (11.0.10+8) (build 11.0.10+8-LTS-162)
# Java VM: Java HotSpot(TM) 64-Bit Server VM 18.9 (11.0.10+8-LTS-162, mixed mode, tiered, compressed oops, g1 gc, windows-amd64)
# Problematic frame:
SELECT * FROM conversations WHERE id1 = '1' OR id2 = '1' ORDER BY lastUpdate DESC LIMIT 9 OFFSET 0;#
CSELECT * FROM accounts WHERE id = 16;
[sqlite-3.30.1-03ac4057-b812-49a1-9a10-f02ba1c22986-sqlitejdbc.dll+0x537d]
#
# No core dump will be written. Minidumps are not enabled by default on client versions of Windows
#
# An error report file with more information is saved as:
# C:\Users\paRa\AppData\Local\Temp\\hs_err_pid13536.log
#
# If you would like to submit a bug report, please visit:
# https://bugreport.java.com/bugreport/crash.jsp
# The crash happened outside the Java Virtual Machine in native code.
# See problematic frame for where to report the bug.
#
From what I saw on other posts, this error message should point where the error is located, in my case if I go to the specific lines where those SQL queries are executed, I have no error.
What it should be noted is that when I put a break point in the API of the activeConversations function, the server never crashes, so I was thinking that it had something to do with how much information is being handled. However, there isn't much information transferred at the moment since I don't have that much information in the database.
Solution
The most likely explanation (outside of a bug in sqlite) is that the JVM is running the webserver with a lot of threads but the sqlite configuration is using single threaded mode and thus causing memory corruption.
Check that you are starting/configuring the sqlite with at least multi threaded mode.
https://sqlite.org/threadsafe.html
Answered By - AlBlue
