Created attachment 925807 [details]
Description of problem:
a Packed local domain shouldn't be aloud on any case,it damages host's Performance and can lead to collapsion.
After filling the local domain to almost zero free space,host became very slow.
message on UI:
"Host vdsb has less than 500 MB of free space"
Version-Release number of selected component (if applicable):
Steps to Reproduce:
1.create a local domain and fill it with disks
2014-08-11 16:51:01,162 ERROR [org.ovirt.engine.core.dal.dbbroker.auditloghandling.AuditLogDirector] (DefaultQuartzScheduler_Worker-16) Correlation ID: null, Call Stack: null, Custom Event ID: -1, Message: Critical, Low disk space. Host vdsb has less than 500 MB of free space left on: /var/log/core, /tmp, /var/log, /var/run/vdsm/.
host become's slow.
local domain should have a different space policy from regular sd due to the sensitivity of its location
we can really use a threshold flag which will also block with CDA, operations who violates the space policy,not only warn the user.
for example when RPE,BZ #679070 ,will be operational (I'll refer to #679070 RFE as 'FreeSpaceCriticalLowOnDomainInGB',and to simplify,this feature will be 'FreeSpaceCriticalLowOnDomainFLAG') a user should be able to set a related flag to 'permissive' ,'enforce' . permissive will warn the user,and enforce will block with CNA the operations which violate the free space policy.
Naturally,the configuration of a local domain will be by default:
FreeSpaceCriticalLowOnDomainFLAG -> could not be changed
FreeSpaceCriticalLowOnDomainInGB -> could not be set to integer below SOME_THRESHOLD
The free space threshold can be configured per domain, we won't do anything out of the box here.