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What happens when you create too many threads?
If you create thousands of threads then you will waste time context switching between them and your work will take longer to complete. Instead of manually starting new threads you should use the thread pool to perform your work so Windows itself can balance the optimum number of threads.
How many threads can you have?
Each processor has 10 cores, each core being basically equivalent to a classic single-core CPU on its own. Each core can only run 1 thread at a time, i.e. hyperthreading is disabled. So, you can have a total maximum of 20 threads executing in parallel, one thread per CPU/core.
What is the maximum number of threads?
There is no real limit for threads on an operating system. There may be an operating system specific hard limit. For example on windows machines by default the thread stack reserve has a size of 1MB. That means each thread requires roughly 1MB of memory.
Is there a limit to how many threads you can use?
There are two factors that affect how many threads you should allow for. The first is the number of DB connections available. This may be a hard limit unless you can increase it at the DBMS – I’m going to assume your DBMS can take an unlimited number of connections in this case (although you should ideally be measuring that as well).
When do you have a complication in multithreading?
A complication comes about when the unit of work passed to the thread doesn’t execute a reasonably atomic unit of work. Eg, you may have the thread at one point access the disk, at another point wait on a network.
What happens to the number of threads in a pool?
The number of active threads in this pool can then be tweaked and scaled based on the findings of your profiling, the hardware you are running on, and other things that may be occurring on the machine.
What should the safety factor be for multithreading?
What you should measure specifically is the maximum amount of threads in concurrent use (e.g., waiting on a return from the DB call) under load. Then add a safety factor of 10% for example (emphasised, since other posters seem to take my examples as fixed recommendations).