Synology FS3600 Virtual Machine Manager s White Paper - Page 15

implementations. These include high-performance drives, cache expansions, connectivity enhancements, as well as virtual interface choices that can speed up processes. Hard drives and SSDs The physical drives on your VM's storage node are the most important predictor of virtual drive performance. Different VMs are stored in different locations on physical disks, and running several VMs concurrently can require a large number of random read and write input-output operations per second (IOPS). Traditional HDDs, which have a rotating platter design, may struggle to perform such operations efficiently. Using all-SSD storage for the storage node is recommended and can significantly speed up VM operations. Compatible SSD drives are available for FlashStation, as well as DiskStation and RackStation models. Alternatively, adding SSD cache to your HDD-based setup will significantly speed up virtualized operations. Adding an SSD cache Some Synology NAS models have internal slots for additional SSD cache. For other models, the Synology M2D18 and M2D20 SSD adapters offer an effective way to expand cache memory. Full updated lists of supported SSD modules for each interface are available on our compatibility pages. Consult our Support Center to find out which Synology NAS models support adding SSD cache and using which protocol. Virtual disk interfaces Users have a choice of three virtual disk controllers. In order of rising average speed, users have a choice of IDE, SATA, and VirtIO SCSI. IDE is compatible with almost all operating systems and SATA works with most modern operating systems (released after 2003). VirtIO, the fastest option, is supported in most Linux distributions, while Microsoft Windows requires separate installation of VirtIO drivers. The VirtIO interface is included in the Synology Guest Tool .iso image for Windows available in VMM. A comparison of disk controller performance can be found in Comparing Configurations below. Storage IOPS performance statistics for the latest and older Synology NAS models are constantly updated on our performance pages. Virtual disk space reclamation VMM version 2.3.0 and DSM 6.2 and above support virtual disk space reclamation. With the SCSI UNMAP or ATA TRIM commands available in Windows and most Linux distros, space held by virtual disks in host HDD and SSD storage can be released after files are deleted or disks are formatted. Space reclamation may affect system or disk performance. For more information on remote disk performance, refer to Storage nodes. 13 Configuration Guide