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The XenServer PVS-Accelerator feature offers additional capabilities for customers using XenServer and Citrix Provisioning Services (PVS). PVS is a popular choice for image management and hosting for Citrix Virtual Apps and Desktops. PVS-Accelerator employs a Proxy mechanism that resides in the Control Domain (dom0) of the XenServer. When the PVS Accelerator feature is enabled, Citrix Provisioning targets device (VM) read requests are cached directly on the XenServer host. These requests are cached in physical memory or a storage repository. When subsequent VMs on the target XenServer host make the same read requests, the virtual disk is streamed directly from cache, not from the Citrix Provisioning server. This eliminates the need to stream from the Citrix Provisioning server, thereby considerably reducing network utilization and processing on the server and improving the performance of the VM. Hence, monitoring processing of the read requests and network traffic flow from cached PVS server/client is essential for administrators to identify how efficiently the reads are serviced and the traffic flow that used excessive bandwidth. The XenPVSAccTest test can help administrators to continuously track the flow of read requests.

The test reveals the bandwidth usage for processing the read requests from the cache on the target XenServer host and the type of traffic that is causing excessive bandwidth usage, thereby providing pointers to how the PVS client/server configuration can be fine-tuned in order to reduce bandwidth consumption and improve performance.

Outputs of the test : One set of results for the target XenServer host that is being monitored.

Measurement	Description	Measurement Unit
evicted	Indicates the rate at which the bytes are evicted from the cache on the target Citrix XenServer.	KB/sec
read_total	Indicates the total number of reads received by the cache per second.	Reads/sec
read_hits	Indicates the number of reads serviced from the cache per second.	Hits/sec
read_misses	Indicates the number of reads that cannot be serviced from the cache per second.	Misses/sec
reads_pct	Indicates the percentage of reads serviced from the cache per second.	Percent
client_sent	Indicates the rate which the bytes are transferred from the cached PVS client on the target Citrix XenServer.	KB/sec
server_sent	Indicates the rate which the bytes are transferred from the cached PVS server on the target Citrix XenServer.	KB/sec
proxy_saved	Indicates the rate which the bytes are transferred from the PVS Accelerator instead of the PVS server on the target Citrix XenServer.	KB/sec
space_util	Indicates the percentage of space utilized by the PVS Accelerator compared to the total size of the cache storage on the target XenServer.	Percent