MySQL goes down with only PDO connections.

Lack of assessment perspective.

• Process execution status on DB side and DB side
• Resource status on the DB access executor. (CPU memory)
• Connection pool utilization on the DB access side
• DB resource status, connection count information

It is a minimum I should like to see thatAs you said in the simulation, if you set up a web server in the first step and throw HTTP there, you won't know at all until you look at the number of sessions there.

I'm afraid I'm Esper, but I doubt it in the following order.

• Connection pool exhaustion on the connecting side (not releasing the session)
• Connection exhaustion at destination (normally upper limit as there are no infinite resources)
• Resource exhaustion and session limits at the previous stage

As a general rule, the number of connections is large enough to be an important element of capacity planning, so you must limit them somewhere, so if you don't manage them properly (usually round to middle), they will overflow quickly.If you don't do this, the process will die quickly on both the receiver and the sender...By the way, the larger the system, the upper limit on the number of connections will be set at the middle of the inquiry side, and we will meet there.Since it's a simulator, isn't it directly connected at 800 seconds? If so, is that okay with the system design?

For example, PHP may be writing directly to the PDO without connecting from the middle DB connection pool, but I don't think that's the case, but I can imagine it just by looking at the text...