Bug 789463

make sure you have more than one CPU.  This is a known issue with Ruby and there really isn't anything we can do about it in the short term to solve the fact that long running IO blocks Ruby 1.8.*

We did extensive investigation earlier on that can be summarized here:

https://www.redhat.com/archives/katello-devel/2012-January/msg00042.html

and also this wiki page:

https://fedorahosted.org/katello/wiki/LoadBalancerChoice

In a future version of Katello we may address this but there isn't anything we can do in 1.0

I should have clarified:

* Make sure have more than one CPU on your machine hosting Katello
* Make sure you have more than one thin process configured.  You can see how many you have configured by looking at:

- /etc/katello/thin.yml

servers: 4

-  /etc/httpd/conf.d/katello.conf:

 <Proxy balancer://thinservers>
    BalancerMember http://127.0.0.1:5000/katello
    BalancerMember http://127.0.0.1:5001/katello
    BalancerMember http://127.0.0.1:5002/katello
  ..continue until it matches the # of thin servers configured in the thin.yml..
  </Proxy>

If you update those to more than one you should have more Ruby thin processes to handle inbound requests while the first one handles your manifest upload.

NOTE:  This does not fix the issue but will help. Any request that ends up going to the long running process that is processing the manifest will still block.

[root@qetello02 ~]# cat /etc/katello/thin.yml
--- 
pid: tmp/pids/thin.pid
address: 0.0.0.0
wait: 30
timeout: 30
port: 5000
log: /var/log/katello/thin-log.log
max_conns: 1024
require: []

environment: production
max_persistent_conns: 512
# stop katello prior changing servers option
servers: 5
daemonize: yes
chdir: /usr/share/katello
[root@qetello02 ~]# cat /etc/httpd/conf.d/katello.conf
NameVirtualHost *:443
<VirtualHost *:443>

  ErrorLog /etc/httpd/logs/ssl_kt_error_log
  TransferLog /etc/httpd/logs/ssl_kt_access_log
  LogLevel info

  ProxyRequests Off
  SSLEngine On
  SSLCertificateFile /etc/candlepin/certs/candlepin-ca.crt
  SSLCertificateKeyFile /etc/candlepin/certs/candlepin-ca.key
  SSLCaCertificateFile /etc/candlepin/certs/candlepin-ca.crt
  ProxyPreserveHost Off
  RequestHeader set X_FORWARDED_PROTO 'https'

  # Performance related configurations
  AddOutputFilterByType DEFLATE text/html text/css application/x-javascript application/javascript

  Timeout 5400
  ProxyTimeout 5400

  <Proxy balancer://thinservers>
    BalancerMember http://127.0.0.1:5000/katello
    BalancerMember http://127.0.0.1:5001/katello
    BalancerMember http://127.0.0.1:5002/katello
    BalancerMember http://127.0.0.1:5003/katello
    BalancerMember http://127.0.0.1:5004/katello
  </Proxy>

  Alias /katello/assets "/usr/share/katello/public/assets"
  Alias /katello/images "/usr/share/katello/public/images"
  Alias /katello/fonts "/usr/share/katello/public/fonts"
  Alias /katello/javascripts "/usr/share/katello/public/javascripts"

  ProxyPass /katello/assets !
  ProxyPass /katello/images !
  ProxyPass /katello/fonts !
  ProxyPass /katello/javascripts !
  ProxyPass /katello balancer://thinservers

  ProxyPassReverse /katello balancer://thinservers
  ProxyPassReverse /katello/assets !
  ProxyPassReverse /katello/images !
  ProxyPassReverse /katello/fonts !
  ProxyPassReverse /katello/javascripts !

  <Location /katello>
    RequestHeader set SSL_CLIENT_CERT "%{SSL_CLIENT_CERT}s"
    SSLVerifyClient optional
    SSLRenegBufferSize 262144
    SSLVerifyDepth 2
  </Location>

  <Location /katello/api>
    # report to CLI and RHSM nicely when Katello is down
    ErrorDocument 500 '{"displayMessage": "Internal error, contact administrator", "errors": ["Internal error, contact administrator"], "status": "500" }'
    ErrorDocument 503 '{"displayMessage": "Service unavailable or restarting, try later", "errors": ["Service unavailable or restarting, try later"], "status": "503" }'
  </Location>
</VirtualHost>

NameVirtualHost *:80
<VirtualHost *:80>
  RewriteEngine On
  RewriteCond %{HTTPS} off
  RewriteRule /katello(.*)$ https://%{HTTP_HOST}%{REQUEST_URI}
</VirtualHost>

Manifest imports are async and won't block UI