VDDK 6.7.0 supports parallel reads for high throughput. In your code, use VixDiskLib_ConnectEx and set numThreads to 4-8 depending on your storage backend.
: Includes advanced options for managing encrypted virtual machines and disks.
: This version is backward compatible with vSphere 6.0 and 6.5, and is specifically designed to support ESXi 6.7 and vCenter Server 6.7.
https://download3.vmware.com/software/vddk-6.7.0-670/VMware-vix-disklib-6.7.0-670.x86_64.exe
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