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I'm wondering what's a good number of threads to use?
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We aren't going to be able to give you the answer that you are seeking. What is a good number for your particular situation would be a totally different number for the next persons. I mean you haven't even given any detail about what it is that you are doing AND even if you had it is very unlikely that anyone could give you a number you are looking for.<br />
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SO... what would I do in your situation? Firstly, you mention &quot;give diminishing performance&quot; so I would make sure that you have some way of measuring performance. And then it is a case of trial and error to see what you can get out of it before you performance begins to &quot;diminish&quot;
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If you want maximum throughput you generally only want about twice as many threads as cores on your CPU - so you're looking at maybe 10 rather than 150. &nbsp;But that's assuming you're not going to be blocking and waiting for I/O - which it sounds like you will be if you're making REST calls? &nbsp;In that case it really depends how long the REST calls take to respond and whether the threads will block waiting for the response.<br />
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So the answer is &quot;it depends&quot;.<br />
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Like mccarl said - not really enough info here to help you much.
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Yes, the threads will block while waiting for responses, but that's just because it's easier to program this way- each of the 3 or 4 REST calls are sequential... &nbsp;Of course I could have chained the asynch callbacks instead... &nbsp;So I'm guessing a definite minimum is about 100 threads for this reason. &nbsp;I did something similar about ten years ago and since then computers have gotten faster, and I think my magic number was at about 150. &nbsp;Of course, the two servers are doing different things, but they're basically the same amount of work.<br />
Anyway, I knew this was a vague question.... &nbsp;I'm just fishing for out of the box thinking. &nbsp;Among other things, I was hoping for someone to tell me about something that can add the correct number of threads based on performance, but that's a whole other ball game...
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Hi Experts,<br />
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I'm doing a simulation of a bunch of sessions that do 3 or 4 REST calls. &nbsp;I'd like to do as many as possible simultaneously that won't start degrading the machine and give diminishing performance. &nbsp;I don't care to make it right at the critical point, but I'm wondering what's a good number of threads to use? &nbsp;I'm thinking 150 is likely a good number.<br />
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Thanks for any advice,<br />
Mike
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Hi Experts,

I'm doing a simulation of a bunch of sessions that do 3 or 4 REST calls.  I'd like to do as many as possible simultaneously that won't start degrading the machine and give diminishing performance.  I don't care to make it right at the critical point, but I'm wondering what's a good number of threads to use?  I'm thinking 150 is likely a good number.

Thanks for any advice,
Mike

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