Thanks Brad for replying. In our use case we are doing lot of crunching, DB and external REST service calls? There is a limit on external REST service calls we can make. I can restrict the call to external services using a thread pool. But I was thinking if it is possible to limit when receiving the request, so that we can fail fast rather than limit while making the external call. If request is crossing the limit sending error to the caller is fine.
On 10/1/16, Brad Johnson <[email protected]> wrote: > The first question I'd have is "are you sure you have a problem with the > number of incoming requests?" One of the biggest problems I find in the > field is premature optimization. If you have a fairly good characterization > of the problem, the number of requests anticipated, the length of time to > process the incoming request, etc. you can set up JMeter to stress test > your application. That will let you change configuration options in Camel > and see if the response is more in line with what you are expecting. > > What exactly are you trying to accomplish by limiting concurrent requests? > What do you want to happen if there are too many requests? Are these > request/responses that you are getting and sending data back after some > length operations or are you mostly receiving data to be processed and then > sending an "OK" response back. In the case of the latter you can put the > incoming data on a SEDA queue and immediately return an "OK". Is it that > the incoming request is resulting in a lot of number crunching, database > calls, or other operations that take too long and the number of requests > are bogging things down before sending a response back to the user? > > Camel has a wide range of components that can provide RESTful APIs. They > are all going to be a little different in their behavior. For example, the > Netty component is going to use NIO under the covers to handle incoming > data. > http://camel.apache.org/rest-dsl.html > > If you use Jetty you can look at the min and max settings on the thread > pool. Jetty also has continuations which frees up the incoming request > threads and uses a callback mechanism to send the response back when it is > finished. > http://camel.apache.org/jetty.html > > But really, a bit more detail and code about the use case and what it is > you're trying to do would be helpful. Do you want the request to send an > error to the client if there are too many incoming requests? Why is the > number of concurrent requests a concern? Is the incoming data large chunks > of data that are gobbling up memory or is the processing expensive or ???. > > On Sat, Oct 1, 2016 at 9:43 AM, Debraj Manna <[email protected]> > wrote: > >> Hi >> >> I have seen Throttler <http://camel.apache.org/throttler.html> in camel. >> Is >> there anything available in camel that restricts the number of concurrent >> accesses something like this as mentioned here >> <https://github.com/google/guava/blob/master/guava/src/ >> com/google/common/util/concurrent/RateLimiter.java#L41> >> ? >> >> Also the below seems to be a more generic query but thought of asking >> here >> if anyone can provide some thoughts on this:- >> >> I have observed that most of the RESP APIs does rate limiting on requests >> rather than restricting the number of concurrent requests. Is there any >> specific reason? >> >
