Can you at least tell me how apache settings coordinate with mod_wsgi settings?
I set number of threads, processes in Apache and in mod_wsgi. How do they work together? In mod_wsgi processes=5 threads=12. Does it mean 60 concurrent requests? On Tuesday, August 11, 2020 at 10:31:56 AM UTC+3, Graham Dumpleton wrote: > > The problem was you had other odd requirements like having non thread safe > code. > > All I can do is suggest you watch these videos. > > https://www.youtube.com/watch?v=CPz0s1CQsTE&t=4s > https://www.youtube.com/watch?v=SGleKfigMsk&t=2s > https://www.youtube.com/watch?v=k6Erh7oHvns&t=1s > > There is no simple answer as one needs to know how your application works > and have access to performance metrics from an APM service in order to tune > the server. > > Graham > > On 11 Aug 2020, at 5:27 pm, Paul Royik <[email protected] <javascript:>> > wrote: > > One more question. > > What is a good configuration if I have 500 concurrent requests and there > are no long-running tasks? > > On Tuesday, August 11, 2020 at 9:52:39 AM UTC+3, Paul Royik wrote: >> >> Thank you for your help. >> >> On Tuesday, August 11, 2020 at 8:30:27 AM UTC+3, Graham Dumpleton wrote: >>> >>> If it is a minor quick running script that does something simple it >>> should be okay. It is just having long running processes would be more >>> concerned about. >>> >>> On 11 Aug 2020, at 3:18 pm, Paul Royik <[email protected]> wrote: >>> >>> You are absolutely correct. Need to change the architecture. >>> One more question. I also use subprocess.check_output from django. Is >>> it also bad idea? I'm trying to run a script (non-python) and get it output. >>> >>> On Tuesday, August 11, 2020 at 1:55:51 AM UTC+3, Graham Dumpleton wrote: >>>> >>>> Personally I would be concerned about the architecture you are using if >>>> you have long running tasks like you describe. It is not usually a good >>>> idea to use 'multiprocessing.Process' to create sub processes directly >>>> from >>>> a web server process to perform work. A better architecture would be to >>>> off >>>> load the work into a queue using something like Celery and have the >>>> separate job processing system pull the jobs from the queue and process >>>> them. You would also be better off to model the interaction from the front >>>> end as queueing the job and immediately responding with an acknowledgement >>>> to say is queued. The front end can then start polling periodically to see >>>> if the job has finished, and when it has it would get the response back. >>>> The front end can then display the data or save it locally as needed. >>>> >>>> This model avoids the problem of requests being parked doing nothing >>>> for a long time, which with your server configuration is going to be >>>> hugely >>>> expensive on memory and not scale very well because of limitations of >>>> using >>>> WSGI process/threading model. You might even consider not using a WSGI >>>> application at all. Instead, use an async web application paired with >>>> Celery for execution of the jobs. Using an async web application means you >>>> can handle as many parked requests as you want and they can quite happily >>>> sit there waiting for Celery to finish the job and don't need to use >>>> polling. Only thing am not sure about in that is what async clients there >>>> are for Celery. >>>> >>>> Graham >>>> >>>> On 10 Aug 2020, at 9:09 pm, Paul Royik <[email protected]> wrote: >>>> >>>> My django app makes heavy calculations which can be infinite. >>>> That's why, when user enters the site, i.e. makes a request, heavy >>>> calculations are wrapped into multiprocessing.Process which runs at most 7 >>>> seconds. >>>> I can't use threads, because third-party packages are not thread-safe. >>>> >>>> So, I have around 30 concurrent requests per second. If each request >>>> can take up to 7 seconds, then it is 30*7=210 concurrent requests in the >>>> worst case. >>>> Each of these concurrent requests opens multiprocessing.Process, which >>>> gives (I guess) 210*2=420 (close to 500) concurrent requests in the worst >>>> case. >>>> That' how I got 500 requests. Possibly, my calculations are incorrect. >>>> >>>> Average page load time (average response times) is 10 seconds. >>>> >>>> I use MPM worker. >>>> >>>> I set WSGIProcessGroup >>>> >>>> StartServers 100 >>>> ServerLimit 500 >>>> >>>> ThreadsPerChild 1 >>>> ThreadLimit 1 >>>> >>>> MaxRequestWorkers 500 >>>> MaxConnectionsPerChild 10000 >>>> >>>> WSGIApplicationGroup %{GLOBAL} >>>> WSGIDaemonProcess django_app processes=75 threads=1 python-path='...' >>>> maximum-requests=10000 request-timeout=20 >>>> WSGIProcessGroup django_app >>>> >>>> WSGIRestrictEmbedded On >>>> WSGILazyInitialization On >>>> >>>> >>>> >>>> On Monday, August 10, 2020 at 1:12:30 PM UTC+3, Graham Dumpleton wrote: >>>>> >>>>> What sort of application are you running? >>>>> >>>>> What is your average response times? >>>>> >>>>> Do you have long running requests, if yes, how long? >>>>> >>>>> What Apache MPM are you actually using? >>>>> >>>>> My initial impression is that is a quite poor configuration which is >>>>> only going to chew up huge amounts of memory for no good reason, but I >>>>> don't know your application requirements. >>>>> >>>>> Also, are you even setting WSGIProcessGroup? If it isn't set it makes >>>>> the whole daemon process configuration moot as it isn't even being used. >>>>> >>>>> On 10 Aug 2020, at 7:24 pm, Paul Royik <[email protected]> wrote: >>>>> >>>>> StartServers 50 >>>>> ServerLimit 200 >>>>> >>>>> ThreadsPerChild 1 >>>>> ThreadLimit 1 >>>>> >>>>> MaxRequestWorkers 200 >>>>> MaxConnectionsPerChild 10000 >>>>> >>>>> WSGIApplicationGroup %{GLOBAL} >>>>> WSGIDaemonProcess process processes=75 threads=1 >>>>> >>>>> >>>>> >>>>> Is it enough? Or can it handle only 75 concurrent requests? I don't know >>>>> how to synchronize apache and mod_wsgi settings. >>>>> >>>>> >>>>> -- >>>>> You received this message because you are subscribed to the Google >>>>> Groups "modwsgi" group. >>>>> To unsubscribe from this group and stop receiving emails from it, send >>>>> an email to [email protected]. >>>>> To view this discussion on the web visit >>>>> https://groups.google.com/d/msgid/modwsgi/bce72a22-5047-4d4d-a7cb-1657672b4d3ao%40googlegroups.com >>>>> >>>>> <https://groups.google.com/d/msgid/modwsgi/bce72a22-5047-4d4d-a7cb-1657672b4d3ao%40googlegroups.com?utm_medium=email&utm_source=footer> >>>>> . >>>>> >>>>> >>>>> >>>> -- >>>> You received this message because you are subscribed to the Google >>>> Groups "modwsgi" group. >>>> To unsubscribe from this group and stop receiving emails from it, send >>>> an email to [email protected]. >>>> To view this discussion on the web visit >>>> https://groups.google.com/d/msgid/modwsgi/df05d905-b28c-42ce-bc46-5b754e2ddcbeo%40googlegroups.com >>>> >>>> <https://groups.google.com/d/msgid/modwsgi/df05d905-b28c-42ce-bc46-5b754e2ddcbeo%40googlegroups.com?utm_medium=email&utm_source=footer> >>>> . >>>> >>>> >>>> >>> -- >>> You received this message because you are subscribed to the Google >>> Groups "modwsgi" group. >>> To unsubscribe from this group and stop receiving emails from it, send >>> an email to [email protected]. >>> To view this discussion on the web visit >>> https://groups.google.com/d/msgid/modwsgi/ce91f94b-9c57-464a-9dd2-79d7ad3184c6o%40googlegroups.com >>> >>> <https://groups.google.com/d/msgid/modwsgi/ce91f94b-9c57-464a-9dd2-79d7ad3184c6o%40googlegroups.com?utm_medium=email&utm_source=footer> >>> . >>> >>> >>> > -- > You received this message because you are subscribed to the Google Groups > "modwsgi" group. > To unsubscribe from this group and stop receiving emails from it, send an > email to [email protected] <javascript:>. > To view this discussion on the web visit > https://groups.google.com/d/msgid/modwsgi/50d4fde5-aa0f-483e-8956-8534a485a2d5o%40googlegroups.com > > <https://groups.google.com/d/msgid/modwsgi/50d4fde5-aa0f-483e-8956-8534a485a2d5o%40googlegroups.com?utm_medium=email&utm_source=footer> > . > > > -- You received this message because you are subscribed to the Google Groups "modwsgi" group. 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