90CHAPTER 9: PERFORMANCE MONITORING
To view the I/O Performance graphs:
1Log in to the Web interface.
2Select Performance
3Select I/O Performance Graphs from the available graph types. Select one of the three available time periods, Daily, Weekly, or Monthly, by clicking the appropriate radio button.
4Click OK.
The I/O Performance graphs show the following information, which is updated every 5 minutes:
■Disk Activity (sec -1)
The average number of disk operations per second to the caching disk(s).
■Network Packets (sec -1)
The average number per second of TCP packets sent to and received by the Webcache.
■New TCP Connection (sec -1)
The average number per second of TCP connections established by the Webcache.
■DNS Lookups (sec -1)
The average number per second of Domain Name System (DNS) server requests sent to the Webcache.
■DNS Hit Rate (%)
The average percentage of Domain Name System (DNS) server requests served by the Webcache. This is calculated as the ratio of host database hits to host database requests.
The Webcache has its own internal cache of DNS entries. The DNS Hit Rate shows how effective this cache is being in avoiding DNS lookups to the DNS server.
