In the case of a small dataset, if customers observe performance degradation, this workaround will help the customer to restore the performance.
In the case of the small dataset ( working dataset < 5GB), the user might observe performance degradation.
Disabling DomClientReadCache shows a significant reduction in CPU usage and an enhancement in overall performance, particularly in scenarios involving large datasets. This is attributed to the fact that the current cache size is insufficient to yield performance benefits due to a low cache hit ratio. Consequently, the decision was made to maintain DomClientReadCache as disabled by default.
However, in situations involving small datasets, DomClientReadCache could effectively store data in the cache since working datasets are small. Despite this, we opted to disable DomClientReadCache by default to address performance concerns in general cases, resulting in a performance drawback for scenarios involving small datasets.
Currently there is no resolution to the issue.
To workaround the issue, please enable the client-cache with an advanced config option:
esxcfg-advcfg -s 1 /VSAN/DomClientReadCache
Note: The DomClientReadCache is disabled in VSAN version 8.0u2. This workaround will be required for VSAN versions later than 8.0u2.