[ome-users] Improving webclient performance

[Aleksandra Tarkowska (Staff)]

Hi Paul,

could you provide output of

- bin/omero admin diagnostics
- ps aux | grep gunicorn
- copy of your nginx.conf and omero-web.conf

Are you using any proxy server in front of nginx?

It is possible that bsession is slow, could you set public user, and import one of our example P-TRE images from http://downloads.openmicroscopy.org/images/DV/ . It will be easier to compare with benchmark on http://www.openmicroscopy.org/site/support/omero5.2/sysadmins/unix/install-web/install-nginx.html


Thanks
Ola

> On 10 May 2016, at 14:35, Paul van Schayck <paul at vanschayck.nl> wrote:
>
> Dear all,
>
> I've been looking into the OMERO.web requests time. We sometimes have
> the feeling that the interface is a bit sluggish, and could respond
> more snappy. So I've done some small tests.
>
> Note that this is not a detailed analysis yet. But based on viewing
> the logs and doing some small experiments for an hour or two.
>
> * Tests done on Ubuntu 14.04 VM with nginx and gunicorn. 4 cores, 4
> GiB of memory. Increased shared memory settings for postgresql. No
> other load on the server.
>
> * Requests to 404 pages of OMERO.web have a typical response time of
> 25 ms. Leading me to believe that the nginx/gunicorn combination gives
> relative little overhead.
>
> * Requests to real OMERO pages (like metadata details, the main index
> or for example a tile) give about a time anywhere between 400 and 500
> ms. With sometimes outliers to 300ms or 600ms.
>
> * Because I saw so little difference between metadata details or an
> image tile I opted to just get the main index page. I used this
> command in the end for most testing:
>
> curl "http://omero.local/webclient/?server=1&bsession=21145499-5e24-451c-b5de-5b95c95d7c9a"
> -w "time_starttransfer:  %{time_starttransfer}, time_total:
> %{time_total}\n" -o /dev/null
>
> A typical request would give this output:
>
> time_starttransfer:  0,412 s, time_total:  0,415 s
>
>
> Looking at this representative Blitz.log (also attached) the following
> things stood out for me:
>
> * The time spent directly in OMERO is about 383 ms. Confirming again
> that the network, nginx and gunicorn overhead is low as the total
> request (as seen from the client was 415 ms)
>
> * There are 13 calls to getConfigValue. In total spending about 143 ms.
>
> * The queries executed are only a few ms.
>
> * There is a (unexplained for me) gap between two queries of 80 ms.
>
>
> What really struck me is the 13 calls to getConfigValue taking so much
> time. In general this is about 25% of the request time. Especially as
> those values will in general be static between requests. Is there
> something wrong on my side? Is there anything else I can do to speed
> up web requests?
>
> Thanks,
>
> Paul van Schayck
> <Blitz.log>
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