I've managed to test whether read/write speed is configurable and I arrived with a conclusion that it is. You can change the read/write speed by changing the storage capacity.
Please check the images below:
This is a screenshot before changing the storage capacity:

And this is after changing the capacity:

I also noticed that if you're using HDD, write speed is higher than read speed:

You can only change storage capacity if an instance is already deployed. You can only select storage type when creating a new instance.
With regards write speed is over the limit, we can't make specific claims when changing thread value. There are several factors that this may cause:
- Workload performance could impact read/write speed depending on the characteristics of the workload. Workloads which are heavily multi-threaded or take advantage of high levels of parallelism may experience performance improvements when hyper-threading is enabled. Single-threaded or those with limited parallelism may see little to no benefit.
- Enabling hyper-threading increases the number of logical CPU cores only visible to the OS, which could result in increased context-switching overhead and potential resource contention or conflict over a shared resources between components, i.e., CPU, storage, RAM. This may have a slight impact on the performance of certain workloads.
It is recommended to monitor the performance metrics and conduct thorough testing before performing changes to the thread count in a Cloud SQL PostgreSQL instance.
pool = pond.New(10, 5000); for ... { pool.Submit( ... ) } ; pool.StopAndWait()using github.com/alitto/pond