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Large I/Os are split into 64 KB units when using LSILogic Driver (9645697)


In Windows XP virtual machines using the LSILogic driver, I/Os of a size larger than 64 KB may be split into multiple I/Os of a maximum size of 64 KB. This might adversely affect I/O performance.


You may be able to improve I/O performance by editing the registry entry

Refer to the section Large Block Size Support in the LSI Fusion-MPT Device Management User's Guide

Note: The preceding link was correct as of November 5, 2014. If you find the link is broken, provide feedback and a VMware employee will update the link.

For more information see Guest Operating System Storage Considerations in the Performance Best Practices for VMware vSphere 5.0.

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