startserver | Yet another http server just for fun | HTTP library

It's strange but the problem was with this import { GraphQLDateTime } from 'graphql-iso-date'; package.

After removing it from the schema, it started working.

FYI this was resolved instead, by not letting the connection expire for the lifetime of the application (container in Kubernetes Pod). It renews the lease on the current credentials before they expire instead of trying to load new credentials.

On the client side, you should use a PrintWriter instead of a DataOutputStream to write data to the server:

Create a signal

It is resolved by upgrading ktor version to 1.3.2 or higher

Each goroutine must defer a recover call to recover from a potential panic if you want other goroutine to not be impacted.

Instead of

No tool will give you that kind of metric because the best configuration depends greatly on your php scripts. If you have 4 cores and each request consumes 100% of one core for 1 second, the server will handle 4 request per second in the best case regardless of your mpm and php configuration. The type of hardware you have is also important. Some CPUs perform multiple times better than others.

Since you are using php_fpm, the apache mpm configuration will have little effect on performance. You just need to make sure the server doesn't crash with too many requests and have more apache threads than php processes. Note that the RAM is not the only thing that can make a server unreachable. Trying to execute more process than the CPU can handle will increase the load and the number of context switches, decrease the CPU cache efficiency and result in even lower performance.

The ideal number of php processes depends on how your scripts use CPU and other resources. If each script uses 50% of the time with I/O operations for example, 2 processes per core may be ideal. Assuming that those I/O operations can be done in parallel without blocking each other.

You'll also need to take into account the amount of resources used by other processes such as the DB. SQL databases can easily use more resources than the php scripts themselves.

Spare Servers and Spare Threads are the number of processes/threads that can be idle waiting for work. Creating threads takes time, so it's better to have them ready when a request arrives. The downside is that those threads will consume resources such as RAM even when idle, so you'll want to keep just enough of them alive. Both apache and php_fpm will handle this automatically. The number of idle threads will be reduced and increased as needed, but remain between the minimum and maximum values set in the configuration. Note that not all apache threads will serve php files as some requests may be fetching static files, therefore you should always have more apache threads than php processes.

Start Server and Start Threads represents just the number of processes/threads created during the startup. This have almost no effect on performance since the number of threads will be immediately increased or reduced to fit the values of Spare Threads.

MaxConnectionsPerChild and max_requests are just the maximum amount of requests executed during the process/thread life. Unless you have memory leaks, you won't need to tune those values.

To answer your question...

Why does my compiler suddenly say my app Express object is a Router object...

It doesn't. You can see a reference to the Router.use() function because it is just eventually called inside the app.use() function.

The actual issue here as mentioned in the error message is the middleware function being undefined. This is because inside your swagger.ts file, you specified swaggerUi.server as the middleware function but it needs to be changed to swaggerUi.serve.