Citrix release today the first update for XenServer 5.5 :
Changes included in this update
When LVHD snapshots are deleted, disk space is reclaimed by freeing unused snapshot data. This is provided automatically by XenServer while VMs continue to run. However, there is a known limitation in the 5.5 implementation of this feature: when all snapshots are deleted for a given VM?s disks, some disk space allocated to these snapshots may remain. To address this limitation, Update 1 includes an ‘Off-line Coalesce’ tool that can reclaim all disk space previously allocated to deleted snapshots while the VM is temporarily set offline. The Off-line Coalesce tool and its use are described in full in an associated KB article: CTX123400.
CA-30569, CA-32164, CA-30200
Fixed various ‘Application Errors’ in XenCenter.
XenCenter saved searches are now visible under ‘Apply Saved search’ and ‘Delete saved search’ options.
Big improvements to XenCenter performance when connecting to multiple pools.
Snapshot errors after upgrade from 5.0 to 5.5. Previously released as hotfix XS55E001 and documented in KB article CTX122142.
When multipathing is disabled, then this information is now correctly displayed in XenCenter.