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If users accessing a web server complain of slowness, administrators must be able to quickly figure out what is causing the slowness – is it because of a processing bottleneck with the web server? or is it owing to a latent server network? The CtxNsIsWebSrvTest test accurately points administrators to the source of the slowness!

This test tracks requests to each web server managed by NetScaler ADC and reports the time every server takes to process the requests. The test, thus sends out proactive alerts to administrators if it finds that any web server is responding very slowly to client requests. Additionally, the test also indicates if the slowdown experienced by the user can be attributed to a latent server-side network. This way, the test helps administrators identify slow servers and rapidly isolate the reason for the slowness, so that the problem can be fixed quickly and normalcy restored in no time.

Measurement	Description	Measurement Unit	Interpretation
Hits	Indicates the number of requests received by this web server.	Number	This is a good indicator of the load on the web server. Compare the value of this measure across web servers to know which server is receiving the maximum number of requests. If a single server appears to be servicing a significantly large number of requests than the rest, it could imply that the server is overloaded. This in turn indicates that a faulty/ineffective load-balancing algorithm is in use. Use the detailed diagnosis of this measure to know which NetScaler is managing this web server, so that the load-balancing logic of that NetScaler appliance can be reconfigured to avoid overloads.
Bandwidth	Indicates the total amount of data received by this web server.	KB	Compare the value of this measure across web servers to know which server is consuming bandwidth excessively.
Server_processing_time	Indicates the elapsed time, from when the server starts to receive the first byte of a request from the NetScaler appliance until the NetScaler appliance receives the first byte to response.	Msecs	A high value for this measure indicates that the web server is processing requests slowly. Compare the value of this measure across web servers to isolate the slowest web server. In the event that a user complains of slowness, you can compare the value of this measure with that of the Server_network_latency measure to determine what is causing the slowness – the poor processing power of the web server? or a latent server network?
Server_network_latency	Indicates the average latency caused by the server network.	Msecs	A high value for this measure indicates that the server network is latent. Compare the value of this measure across web servers to know which server’s network is the slowest. In the event that a user complains of slowness, you can compare the value of this measure with that of the Server_processing_time measure to determine what is causing the slowness – the poor processing power of the web server? or a latent server network?
Cache_hits	Indicates the number of requests from this web server that were serviced by the cache.	Number	If the value of this measure is the same as that of the Hits measure, it implies that the web server has serviced all requests to it using the cache. This is indicative of optimal cache size and usage. On the other hand, if the value of this measure is much lower than that of the Hits measure, it could indicate improper cache sizing and ineffective cache usage. This measure will not be reported for Citrix NetScaler Insight versions lesser than v11.x.
Cache_miss	Indicates the number of requests to this web server that were not serviced by the cache.	Number	Ideally, the value of this measure should be 0 or at least, very low. If the value is the same as that of the Hits measure, it could indicate improper cache sizing and ineffective cache usage. This measure will not be reported for Citrix NetScaler Insight versions lesser than v11.x.
Cache_hit_ratio	Indicates the percentage of requests to this web server that were serviced by the cache.	Percent	Ideally, the value of this measure should be > 80%. A low hit ratio on the other hand indicates that a majority of web requests were serviced by the origin server and not the cache server. This can significantly increase request processing time and related overheads. This measure will not be reported for Citrix NetScaler Insight versions lesser than v11.x.
Cache_bypass	Indicates the number of requests that were serviced by the origin server, because the cache server was bypassed.	Number	This measure will not be reported for Citrix NetScaler Insight versions lesser than v11.x.
Cache_hits_bw_consumed	Indicates the bandwidth consumed when requests to this web server were serviced by the cache server.	KB	The difference between the value of the Avg bandwidth measure and this measure for a web server will reveal the bandwidth that may have been saved by request caching. Where cache is well-sized and used optimally, this difference will be high. You can compare this difference across web servers to know which web server is making the most effective use of the cache. This measure will not be reported for Citrix NetScaler Insight versions lesser than v11.x.
Cache_miss_bw_consumed	Indicates the bandwidth consumed when the cache server could not serve the requests to this web server.	KB	The difference between the value of this measure and the value of the Cache_miss_bw_consumed measure for a web server will reveal how much bandwidth was saved by cache hits. This measure will not be reported for Citrix NetScaler Insight versions lesser than v11.x.
Cache_bypass_bw_consumed	Indicates the bandwidth consumed when the cache server was bypassed and the request was served from this origin server.	KB	If the difference between the value of this measure and that of the Cache_miss_bw_consumed measure results in a ‘positive’ integer, it indicates that cache usage has saved considerable bandwidth. This measure will not be reported for Citrix NetScaler Insight versions lesser than v11.x.