6.5.1

Table Of Contents
Table 177. VOMA Command Options (Continued)
Command Option Description
-v | --version
Display the version of VOMA.
-h | --help
Display the help message for the VOMA command.
For more details, see the VMware Knowledge Base article 2036767.
Configuring VMFS Pointer Block Cache
You can use advanced VMFS parameters to configure the pointer block cache.
As the size of the virtual machine files on the VMFS datastores increases, the number of pointer blocks
used by those files also increases. The pointer blocks are used to address file blocks in the large virtual
machine files and virtual disks on the VMFS datastore.
You can configure the minimum and maximum sizes of the pointer block cache on each ESXi host. When
the size of the pointer block cache approaches the configured maximum size, an eviction mechanism
removes some pointer block entries from the cache.
Base the maximum size of the pointer block cache on the working size of all open virtual disk files that
reside on VMFS datastores. All VMFS datastores on the host use a single pointer block cache.
The minimum value is based on the minimum guaranteed memory that the system can allocate to the
cache. 1 TB of open file space requires approximately 4 MB of memory.
To configure the minimum and maximum values for the pointer block cache, use the Advanced System
Settings dialog box of the vSphere Web Client
Table 178. Advanced Parameters to Regulate Pointer Block Cache
Parameter Values Description
VMFS3.MaxAddressableSpaceTB
Default value is 32 (in TB). Maximum size of all open files that VMFS
cache supports before eviction starts.
VMFS3.MinAddressableSpaceTB
Default value is 10 (in TB). Minimum size of all open files that VMFS
cache guarantees to support.
You can use the esxcli storage vmfs pbcache command to obtain information about the size of the
pointer block cache and other statistics. This information assists you in adjusting minimum and maximum
sizes of the pointer block cache, so that you can get maximum performance.
Set Advanced Host Attributes
You can set advanced attributes for a host.
Caution Changing advanced options is considered unsupported. Typically, the default settings produce
the optimum result. Change the advanced options only when you get specific instructions from VMware
technical support or a knowledge base article.
vSphere Storage
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