<html><head><meta http-equiv="Content-Type" content="text/html charset=utf-8"></head><body style="word-wrap: break-word; -webkit-nbsp-mode: space; -webkit-line-break: after-white-space;" class="">Hello,<div class=""><br class=""></div><div class="">I’ve got the following setup, each application on its own virtual machine:</div><div class=""><br class=""></div><div class="">Client <i class="">(sends http-requests to proxy)</i>—> Squid <i class="">(sends http-requests to apache based on destination IP and round robin to multiple apache machines)</i> —> Apache <i class="">(setting up a two way ssl to the requested server)</i> —> HTTPS-server</div><div class=""><br class=""></div><div class="">This setup works great, and I have the Apache and the HTTPS-server its performance tuned. Both can handle 2000 concurrent connections of file sizes up to 10MB.</div><div class=""><br class=""></div><div class="">Unfortunately I haven’t been successful with the Squid-server. After a while I’m getting the following error messages in the log:</div><div class=""><i class=""><b class=""><font color="#e32400" class="">1429432828.200 62854 10.10.7.16 TCP_MISS_ABORTED/000 0 GET <a href="http://https.example.com/index.html" class="">http://https.example.com/index.html</a> - ROUNDROBIN_PARENT/192.168.0.20 -</font></b></i></div><div class=""><br class=""></div><div class="">The Squid virtual machine contains the following:</div><div class=""><i class="">CentOS 7.1 with latest updates</i></div><div class=""><i class="">Squid Cache: Version 3.3.8</i></div><div class=""><i class="">CPU: Intel Xeon E312xx (Sandy Bridge) - 1799.998 MHz (4 cores)</i></div><div class=""><i class="">Memory: 4096 MiB</i></div><div class=""><i class="">Harddisk: 10 GiB, SCSI, raw, cache none</i></div><div class=""><br class=""></div><div class="">When I execute a performance test with 2000 concurrent connections handling a file size of 10KB on each request.</div><div class=""><div class=""><i class=""># ab -n 10000 -c 2000 -X 10.10.7.15:3128 <a href="http://https.example.com/index.html" class="">http://https.example.com/index.html</a></i></div><div class=""><i class="">This is ApacheBench, Version 2.3 <$Revision: 1430300 $></i></div><div class=""><i class="">Copyright 1996 Adam Twiss, Zeus Technology Ltd, <a href="http://www.zeustech.net/" class="">http://www.zeustech.net/</a></i></div><div class=""><i class="">Licensed to The Apache Software Foundation, <a href="http://www.apache.org/" class="">http://www.apache.org/</a></i></div><div class=""><i class=""><br class=""></i></div><div class=""><i class="">Benchmarking <a href="http://https.rinis.nl" class="">https.rinis.nl</a> [through 10.10.7.15:3128] (be patient)</i></div><div class=""><i class="">Completed 1000 requests</i></div><div class=""><i class="">Completed 2000 requests</i></div><div class=""><i class="">Completed 3000 requests</i></div><div class=""><i class="">Completed 4000 requests</i></div><div class=""><i class="">Completed 5000 requests</i></div><div class=""><i class="">Completed 6000 requests</i></div><div class=""><i class="">Completed 7000 requests</i></div><div class=""><i class="">Completed 8000 requests</i></div><div class=""><i class=""><font color="#e32400" class="">apr_pollset_poll: The timeout specified has expired (70007)</font></i></div><div class=""><i class="">Total of 8610 requests completed</i></div></div><div class=""><br class=""></div><div class="">I have the command "vmstat 5” running on the squid server:</div><div class=""><div class=""><i class="">procs -----------memory---------- ---swap-- -----io---- -system-- ------cpu-----</i></div><div class=""><i class=""> r b swpd free buff cache si so bi bo in cs us sy id wa st</i></div><div class=""><i class=""> 2 0 0 3823916 764 124992 0 0 519 26 237 503 2 3 92 3 0</i></div><div class=""><i class=""> 0 0 0 3823744 764 125072 0 0 0 0 44 79 0 0 100 0 0</i></div><div class=""><i class=""> 0 0 0 3823776 764 125044 0 0 0 2 39 70 0 0 100 0 0</i></div><div class=""><i class=""> 0 0 0 3729540 764 139116 0 0 1 0 2145 257 1 2 97 0 0</i></div><div class=""><i class=""> 0 0 0 3728432 764 139888 0 0 0 46 2297 594 1 1 97 0 0</i></div><div class=""><i class=""> 0 0 0 3726484 764 140892 0 0 0 39 2869 581 2 1 97 0 0</i></div><div class=""><i class=""> 0 0 0 3725528 764 141376 0 0 0 0 2843 648 2 2 96 0 0</i></div><div class=""><i class=""> 0 0 0 3724980 764 142008 0 0 0 69 2824 529 2 1 97 0 0</i></div><div class=""><i class=""> 0 0 0 3724584 764 142540 0 0 0 0 2742 472 2 1 97 0 0</i></div><div class=""><i class=""> 0 0 0 3723696 764 143004 0 0 0 0 2511 577 2 1 97 0 0</i></div><div class=""><i class=""> 0 0 0 3722840 764 143200 0 0 0 12 884 228 1 1 99 0 0</i></div><div class=""><i class=""> 0 0 0 3722704 764 142900 0 0 0 0 136 127 0 0 100 0 0</i></div><div class=""><i class=""> 0 0 0 3722504 764 142744 0 0 0 0 40 70 0 0 100 0 0</i></div><div class=""><i class=""> 0 0 0 3722456 764 142784 0 0 0 114 37 68 0 0 100 0 0</i></div><div class=""><i class=""> 0 0 0 3722208 764 142832 0 0 0 0 41 68 0 0 100 0 0</i></div><div class=""><i class=""> 0 0 0 3722480 764 142280 0 0 0 0 179 82 0 0 100 0 0</i></div><div class=""><i class=""> 0 0 0 3722544 764 142140 0 0 0 7 41 75 0 0 100 0 0</i></div><div class=""><i class="">procs -----------memory---------- ---swap-- -----io---- -system-- ------cpu-----</i></div><div class=""><i class=""> r b swpd free buff cache si so bi bo in cs us sy id wa st</i></div><div class=""><i class=""> 1 0 0 3722544 764 142136 0 0 0 0 36 67 0 0 100 0 0</i></div><div class=""><i class=""> 0 0 0 3722996 764 141552 0 0 0 0 42 75 0 0 100 0 0</i></div><div class=""><i class=""> 0 0 0 3722980 764 141568 0 0 0 0 37 68 0 0 100 0 0</i></div><div class=""><i class=""> 0 0 0 3723028 764 141524 0 0 0 0 36 66 0 0 100 0 0</i></div><div class=""><i class=""> 0 0 0 3736816 764 130352 0 0 0 0 809 114 0 0 99 0 0</i></div><div class=""><i class=""> 0 0 0 3737544 764 130268 0 0 0 41 42 74 0 0 100 0 0</i></div></div><div class=""><br class=""></div><div class="">It looks like the hardware has enough resources during the benchmark test.</div><div class=""><br class=""></div><div class="">I’ve got the following squid.conf running:</div><div class=""><div class=""><i class="">cache_peer 192.168.0.18 parent 3128 0 round-robin no-query no-digest</i></div><div class=""><i class="">cache_peer 192.168.0.20 parent 3128 0 round-robin no-query no-digest</i></div><div class=""><i class=""><br class=""></i></div><div class=""><i class="">acl development_net dst 192.168.0.0/24</i></div><div class=""><i class="">cache_peer_access 192.168.0.18 allow development_net</i></div><div class=""><i class="">cache_peer_access 192.168.0.20 allow development_net</i></div><div class=""><i class=""><br class=""></i></div><div class=""><i class="">never_direct allow all</i></div><div class=""><i class="">cache deny all</i></div><div class=""><i class=""><br class=""></i></div><div class=""><i class="">maximum_object_size_in_memory 16 MB</i></div><div class=""><i class="">cache_mem 2048 MB</i></div></div><div class=""><br class=""></div><div class="">The squid must not cache at all.</div><div class=""><br class=""></div><div class="">Any help is welcome.</div><div class=""><br class=""></div><div class="">Abdelouahed</div></body></html>