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<p class="MsoNormal"><span style="color:#1F4E79">Dear list,<o:p></o:p></span></p>
<p class="MsoNormal"><span style="color:#1F4E79"><o:p> </o:p></span></p>
<p class="MsoNormal"><span lang="EN-US" style="color:#1F4E79">once in a while we’re experiencing some stability issues on our productive MapProxy server. The server stops responding and only a reboot helps to solve the problem. Currently we’re using a script
which checks periodically if the server is responding and if not performs a reboot.<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US" style="color:#1F4E79"><o:p> </o:p></span></p>
<p class="MsoNormal"><span lang="EN-US" style="color:#1F4E79">We’re running MapProxy as recommended through mod_wsgi in Apache. When the error occurs the last lines of the Apache error log shows something like this:<o:p></o:p></span></p>
<p class="MsoNormal" style="text-autospace:none"><span lang="EN-US" style="font-size:9.0pt;font-family:"Lucida Console"">[Tue Jan 12 09:16:18.075153 2016] [mpm_prefork:error] [pid 1122] AH00161: server reached MaxRequestWorkers setting, consider raising the
MaxRequestWorkers setting<o:p></o:p></span></p>
<p class="MsoNormal" style="text-autospace:none"><span lang="EN-US" style="font-size:9.0pt;font-family:"Lucida Console"">[Tue Jan 12 09:18:48.765912 2016] [core:error] [pid 30268] [client ...] Script timed out before returning headers: mapproxy_server.py<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US" style="color:#1F4E79"><o:p> </o:p></span></p>
<p class="MsoNormal"><span lang="EN-US" style="color:#1F4E79">The mapproxy log reveals no further information.
<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US" style="color:#1F4E79"><o:p> </o:p></span></p>
<p class="MsoNormal"><span lang="EN-US" style="color:#1F4E79">I already tried to increase the MaxWorkers setting without real success? This is our Apaches mpm_prefork.conf:
<o:p></o:p></span></p>
<p class="MsoNormal" style="text-autospace:none"><span lang="EN-US" style="font-size:9.0pt;font-family:"Lucida Console""><IfModule mpm_prefork_module><o:p></o:p></span></p>
<p class="MsoNormal" style="text-autospace:none"><span lang="EN-US" style="font-size:9.0pt;font-family:"Lucida Console""> StartServers 5<o:p></o:p></span></p>
<p class="MsoNormal" style="text-autospace:none"><span lang="EN-US" style="font-size:9.0pt;font-family:"Lucida Console""> MinSpareServers 5<o:p></o:p></span></p>
<p class="MsoNormal" style="text-autospace:none"><span lang="EN-US" style="font-size:9.0pt;font-family:"Lucida Console""> MaxSpareServers 10<o:p></o:p></span></p>
<p class="MsoNormal" style="text-autospace:none"><span lang="EN-US" style="font-size:9.0pt;font-family:"Lucida Console""> MaxRequestWorkers 600<o:p></o:p></span></p>
<p class="MsoNormal" style="text-autospace:none"><span lang="EN-US" style="font-size:9.0pt;font-family:"Lucida Console""> ServerLimit 600<o:p></o:p></span></p>
<p class="MsoNormal" style="text-autospace:none"><span lang="EN-US" style="font-size:9.0pt;font-family:"Lucida Console""> MaxConnectionsPerChild 0<o:p></o:p></span></p>
<p class="MsoNormal" style="text-autospace:none"><span lang="EN-US" style="font-size:9.0pt;font-family:"Lucida Console""></IfModule><o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US" style="color:#1F4E79"><o:p> </o:p></span></p>
<p class="MsoNormal"><span lang="EN-US" style="color:#1F4E79">Has anyone experienced similar issues? Is it simply a scaling issue or are there other things to consider? Could the cache storage format be a bottleneck? For the service in question we’re using
a SQLite Cache which is located on a network share and accessed by three MapProxy-servers.<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US" style="color:#1F4E79"><o:p> </o:p></span></p>
<p class="MsoNormal"><span lang="EN-US" style="color:#1F4E79">Kind regards,<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US" style="color:#1F4E79"><o:p> </o:p></span></p>
<p class="MsoNormal"><span lang="EN-US" style="color:#1F4E79">Dirk</span><span style="font-size:10.0pt;font-family:"Verdana",sans-serif;color:#595959;mso-fareast-language:DE"><o:p></o:p></span></p>
<p class="MsoNormal"><o:p> </o:p></p>
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