Hi Tamara,
Sorry for the late reply. It’s mainly because I have no definitive
solution on how to resolve the issue.
My knowledge of PHP is limited, but I assume that the socket_recv
function raises an error and returns false instead of the buffer size
[1,2]. You could try to check the return value, maybe like this?
if ($this->bsize == false) {
throw new BaseXException(socket_strerror(socket_last_error()));
}
The error message might give us a clue as to what goes wrong.
Reading some more pages of the PHP socket documentation, it would
probably be best to check the return type of all other socket
functions as well, as all of them seem to return false instead of
raising an exception.
Hope this helps. If you decide to revise the client code, I invite you
to provide us with the new version!
Christian
[1]
https://github.com/BaseXdb/basex/blob/main/basex-api/src/main/php/BaseXClient/Session.php#L161
[2] https://www.php.net/manual/de/function.socket-recv.php
On Wed, Jan 25, 2023 at 6:58 PM Tamara Marnell
<tmarn...@orbiscascade.org> wrote:
>
> 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
>
> --
>
> Tamara Marnell
> Program Manager, Systems
> Orbis Cascade Alliance (orbiscascade.org)
> Pronouns: she/her/hers
