[ome-users] Problem with omero *downloads* from web - still having problems...

[Jake Carroll]

Hi again,



It looks like the suggestions below do not solve the problem. I have tried with many different combinations of the eventlet string and nothing would appear to fix the issue.

Do you have any other suggestions? 

Thanks!

-jc



>
>
>Today’ Topics:
>
>   1. Format for arguments for OMERO model objects (Paul Kibet Korir)
>   2. Re: Problem with omero *downloads* from web
>
>Message: 2
>Date: Thu, 14 Jan 2016 13:38:48 +0000
>From: "Aleksandra Tarkowska (Staff)" <A.Tarkowska at dundee.ac.uk>
>To: OME User Support List <ome-users at lists.openmicroscopy.org.uk>
>Subject: Re: [ome-users] Problem with omero *downloads* from web
>Message-ID: <BD2B5F53-7A4B-4960-9E15-F816321F3895 at dundee.ac.uk>
>Content-Type: text/plain; charset="utf-8"
>
>Hi Jace and Dave
>
>Sorry for a slow response.
>
>Thanks again for reporting download issue. Failing download is not related to the size of 1GB but Gunicorn worker timeout 30 sec. Your nginx log should show error that upstream prematurely closed connection while reading...
>
>and gunicorn log will say: [CRITICAL] WORKER TIMEOUT (pid:2701)
>
>You can test it by starting web with custom timeout http://docs.gunicorn.org/en/stable/settings.html#timeout
>bin/omero web start --wsgi-args ' -t 5 --error-logfile=/home/omero/omero_dir/var/log/g_error.log '
>
>
>By default OMERO.web runs with gunicorn 5 sync workers with single thread and default timeout 30 sec. Sync workers are preferred for applications that perform complex calculations and async for one that bound (I/O). So you basically need to decide your users will use web for.
>
>You can resolve this problem in two ways depends on download activity and scale by choosing appropriate parameters:
>
>1. async workers:
>
>$ pip install (gevent|eventlet)
>$ bin/omero web start ?-workers INT --wsgi-args ' ?-worker-class (gevent|eventlet) '
>
>
>2. sync workers with multiple threads (this option is available since gunicorn 19):
>(this is less fabulous as request will take up CPU core once is waiting)
>
>$ bin/omero web start ?-workers INT --wsgi-args ? --timeout INT --threads INT '
>depends on python version you may have to pip install futures
>
>
>For more details how to calculate number of workers, threads, etc please refer to the documentation http://docs.gunicorn.org/en/stable/settings.html
>
>You can also run benchmarks tool such as weighttp or Apache ab and do e.g 1000 requests with 100 parallel requests, changing between different kind of workers and see what happens performance-wise.
>
>We will definitely update our documentation to make it clear.
>
>
>Ola
>Software Engineer
>Open Microscopy Environment
>University of Dundee