[Mongrel] [ANN] mongrel_cluster 0.2.2 prerelease

Bradley Taylor bradley at railsmachine.com
Fri Jan 26 00:10:01 EST 2007

Hey y'all:

I've added some new stuff to mongrel_cluster. Give it try and let me 
know if it works for you.

* Added '--clean' to cluster::start to force removal of the pidfile 
before trying to start the cluster member. This is useful for recovering 
from unexpected process death.

* Added '--only PORT' to cluster::* to support running a command on a 
single cluster member identified by its port number (eg, 8001). Inspired 
by Kaspar Schiess.

* Added cluster::status to display basic process status information for 
the cluster. Returns '0' if all processes are found and '2' if a process 
or pidfile is missing. Supports '--only'. Status commands were also 
added to the init.d script, mongrel_cluster_ctl, and the cap recipes.

* The init.d script (resources/mongrel_cluster) will now create 
/var/run/mongrel_cluster and chown to a defined user on start. To fully 
use this feature, update your cluster yml files to store the pidfile in 
/var/run/mongrel_cluster. This will support cleaning up orphaned 
pidfiles at boot time. For example:
pid_file: /var/run/mongrel_cluster/foo.pid

* Fixed a parameter bug with mongrel_cluster_ctl calling mongrel_rails.

How would you use some of these new features? Lets pretend that your 
blog gets spammed by 3000+ comments and 2000+ trackbacks pushing your 
process memory usage to 300mb+. The fair and just Linux kernel, 
displeased by your actions, smites one of your processes using the all 
powerful oom-killer. How do you recover?

$ mongrel_rails cluster::status
Checking 2 Mongrel servers...
Found dog: 8000
Lost dog: 8001

$ mongrel_rails cluster::start --only 8001 --clean
Cleaning 1 pid file...
Starting 1 Mongrel server...

$ mongrel_rails cluster::status
Checking 2 Mongrel servers...
Found dog: 8000
Found dog: 8001

I'm open to suggestions for some different 'status' output. Let me know 
if I broke anything.

Install with:
sudo gem install mongrel_cluster --source 

Bradley Taylor
Rails Machine

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