Description of problem:
Exec summary: /var/lib/qpidd requires 2MB disk space per a content host. That redundantly consumes disk when scaling up number of Content Hosts.
Satellite6 is deployed with default value of efp-file-size=2048 (kB) for qpid broker. That means, a journal file for a durable qpid queue will take 2MB on the disk.
Every Content Host means one durable queue pulp.agent.<UUID> is created. So for every Content Host, /var/lib/qpidd grows up by 2MB in disk space. That is 20GB of disk space for 10k Content Hosts.
Such value is significant enough to be considered when creating disk layout / partitions. Or something we can optimize / decrease substantially by decreasing efp-file-size parameter.
Decreasing the parameter has the only side effect: the journal files would generally get full/obsolete/recycled/rotated faster. But these events occur very seldom, since Satellite/pulp sends to qpidd relatively small number of small/average sized messages only (a message usually has around 1kB, one repo sync means sending less than 100 such messages across more queues).
I see several options here:
1) Add to documentation mention about /var/lib/qpidd disk usage wrt. number of Content Hosts
2) Decrease the parameter to say 256k (8times) just for new deployments (to avoid headache to convert big journals to smallers during upgrade)
3) Decrease the parameter for new deployments and also for upgrades - for this option, there would have to be a tool for converting journals from one journal size to another (not sure if exists but shall be simple to write it)
I dont have strong opinion which option is the best one, as well as I dont know what would be ideal efp-file-size value (that should come up from some testing / measuring, I guess).
Version-Release number of selected component (if applicable):
Sat 6.2 GA (applies to any Sat6 version, though)
Steps to Reproduce:
1. Deploy Sat6
2. Register 10k Content Hosts (to the Sat or to an external Caps, doesnt matter)
3. du -k /var/lib/qpidd
3. shows over 20GB diskspace consumed
3. to show considerably smaller value, or documentation mentions this disk space requirement
Doc BZ raised as https://bugzilla.redhat.com/show_bug.cgi?id=1366517 since either way we chose, the disk requirement is worth to be mentioned in install guide.
Created redmine issue http://projects.theforeman.org/issues/16955 from this bug
Thank you for your interest in Satellite 6. We have evaluated this request, and we do not expect this to be implemented in the product in the foreseeable future. We are therefore closing this out as WONTFIX. If you have any concerns about this, please feel free to contact Rich Jerrido or Bryan Kearney. Thank you.