acefor.blogg.se - Too large for the volumes format

This behavior not only caused metadata lock queues but also prevented standard I/O to a volume from VMs on other ESXi hosts which were not currently holding the lock. In a cluster with multiple nodes, all metadata operations were serialized and hosts had to wait until whichever host, currently holding a lock, released that lock.

Prior to the introduction of VAAI ATS, VMFS used LUN-level locking via full SCSI-2 reservations to acquire exclusive metadata control for a VMFS volume. VMware resolved the first issue with the introduction of Atomic Test and Set (ATS), also called Hardware Assisted Locking.

Per-volume queue limitations on the underlying array.

This limit traditionally was due to two reasons: In the past a recommendation to use a larger number of smaller volumes was made for performance limitations that no longer exist. Using a smaller number of large volumes is generally a better idea today.

The FlashArray supports far larger than that, but for ESXi, volumes should not be made larger than 64 TB due to the filesystem limit of VMFS. A common question when first provisioning storage on the FlashArray is what capacity should I be using for each volume? VMware VMFS supports up to a maximum size of 64 TB.