Issues with builds in Gitlab CI

we are facing sever issues with GIT lab CI, can any help with the issue

PFB the only error in
gitlab_ci_error log. We have increased the timeout value in the Gitlab CI
Config file but the issue still persists.

location @gitlab_ci {

proxy_read_timeout

600;

proxy_connect_timeout 600;

Error:

2015/07/30 14:34:23 [error]
3031#0: *58367 upstream timed out (110: Connection timed out) while reading
response header 22.82, server: build.digital.rbsgrp.mde, request: “POST
//api/v1/builds/register.json HTTP/1.1”, upstream: “http://unix:sockets/gitlab-ci.socket://api/v1/builds/register.json”,
host: “build.digital.rbsgrp.mde”

2015/07/30 15:09:39 [error]
3031#0: *61744 upstream timed out (110: Connection timed out) while reading
response header 35.58, server: build.digital.rbsgrp.mde, request: “GET
/projects/22/builds/2101c4d29a7e054b2eadc47a9ec23ce30c340267 HTTP/data/gitlab_ci/gitlab-ci/tmp/sockets/gitlab-ci.socket:/projects/22/builds/2101c4d29a7e054b2eadc47a9ec23ce30c340267”,
ho

, referrer: “https://build.digital.rbsgrp.mde/projects/22

I have seen the infrastructure
stats of the server and every thing is normal except the RAM usage, Nexus is
taking a lot of memory. PFB list of processes using lot of memory

PID
USER PR NI VIRT RES SHR S
%CPU %MEM TIME+ COMMAND

32368 gitlab_c 25 0 390m 111m 4000 R 92.7
3.1 33:24.52 ruby

10336 gitlab_c 25 0 404m 133m 4000 R 65.0
3.7 4471:19 ruby

2990 mysql 18 0 327m 46m
4656 S 32.0 1.3 2668:52 mysqld

10381 git 18 0 547m 300m
5496 S 6.0 8.2 52:42.32 ruby

these commands are taking
more memory

git
10381 10158 0 Jul29 ? 00:52:44
unicorn_rails worker[1] -D -c /data/git/gitlab/config/unicorn.rb -E production

9102 32368 1 0 Jul31
? 00:34:28 ruby
/data/gitlab_ci/gitlab-ci/vendor/bundle/ruby/1.9.1/bin/puma -C /data/gitlab_ci/gitlab-ci/config/puma.rb
-e production

9102 10336 1 62 Jul29
? 3-02:32:27
/data/gitlab_ci/.rvm/rubies/ruby-1.9.3-p385/bin/ruby
/data/gitlab_ci/gitlab-ci/vendor/bundle/ruby/1.9.1/bin/puma -C /data/gitlab_ci/gitlab-ci/config/puma.rb
-e production