RHEV: Pool VM's generation is too slow and occasionally fails

Issue

• Pool VMs take a very long time to prestart (30 minutes for a pool of 40 VMs, without the CPU, RAM or Storage being taxed at all).
• Constantly got errors during and after the process ends:

2014-06-18 16:21:04,557 INFO  [org.ovirt.engine.core.bll.AttachUserToVmFromPoolAndRunCommand] (ajp-/127.0.0.1:8702-3) [3ef8ad4] Lock Acquired to object EngineLock [exclusiveLocks= key: f80c7702-253f-40aa-9077-1cca8c5784de value: USER_VM_POOL
, sharedLocks= ]
2014-06-18 16:21:04,599 WARN  [org.ovirt.engine.core.bll.AttachUserToVmFromPoolAndRunCommand] (ajp-/127.0.0.1:8702-3) [3ef8ad4] CanDoAction of action AttachUserToVmFromPoolAndRun failed. Reasons:VAR__ACTION__ALLOCATE_AND_RUN,VAR__TYPE__VM_FROM_VM_POOL,VM_POOL_CANNOT_ATTACH_TO_MORE_VMS_FROM_POOL,VAR__ACTION__ALLOCATE_AND_RUN,VAR__TYPE__VM_FROM_VM_POOL
2014-06-18 16:21:04,599 INFO  [org.ovirt.engine.core.bll.AttachUserToVmFromPoolAndRunCommand] (ajp-/127.0.0.1:8702-3) [3ef8ad4] Lock freed to object EngineLock [exclusiveLocks= key: f80c7702-253f-40aa-9077-1cca8c5784de value: USER_VM_POOL
, sharedLocks= ]
2014-06-18 16:21:19,972 INFO  [org.ovirt.engine.core.dal.dbbroker.auditloghandling.AuditLogDirector] (DefaultQuartzScheduler_Worker-50) Correlation ID: null, Call Stack: null, Custom Event ID: -1, Message: Warning, Low disk space. Host FOVIRHEVH05.Intranet.fovissste.gob.mx has less than 1000 MB of free space left on: /var/log.
2014-06-18 16:21:33,821 INFO  [org.ovirt.engine.core.bll.VmPoolMonitor] (DefaultQuartzScheduler_Worker-95) VmPool 0d343f89-2f47-4dd6-8e68-2c01e070f820 is missing 26 prestarted Vms, attempting to prestart 26 Vms
2014-06-18 16:21:34,031 INFO  [org.ovirt.engine.core.bll.VmPoolMonitor] (DefaultQuartzScheduler_Worker-95) VmPool 1b03acb9-0db9-4b96-a92d-133d9d349edd is missing 5 prestarted Vms, attempting to prestart 5 Vms