Hello everyone,

Once in a while, my server running BaseX will suddenly experience a big spike in write operations, the hard disk space will fill up to 100%, and the whole server will lock up. I can't say what initiates this, because the logs and metrics disprove every theory I can think of. (There's nothing unusual in the access logs or BaseX data logs, memory usage stays consistently at 45% and CPU usage at 5%, no user attempted anything like a huge bulk upload, etc.)

However, one thing that always happens during these incidents is that the Apache error log blows up to a crazy size like 1 GB, filled with the message:

PHP Notice:  Trying to access array offset on value of type null in /[path]/client/session.php on line 164

This line is in the read method of the Session class from GitHub, and it indicates that the byte position passed to the buffer property is null. My error log probably fills up because read() is called by readString() in a while loop that never terminates. There might be extraordinary circumstances in which during construction, socket_connect returns "true" but the response is not valid or expected.

-Tamara

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