Sun Microsystems Sun Java System Web Server 7.0, Manual

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CacheEntries 4/1024
HitRatio 62854802/62862912 ( 99.99%)
AsyncDNS Data:
------------------
enabled yes
NameLookups 0
AddrLookups 0
LookupsInProgress 0
The following example shows the DNS Cache information as displayed in the Admin Console:
TABLE 2–6
DNS Cache Statistics
Total Cache Hits 62854802
Total Cache Misses 6110
Number of Asynchronous Lookups 0
Lookups in Progress 4
Asynchronous Lookups Enabled 1
Number of Asynchronous Address Lookups
Performed 0
Enabled
If the DNS cache is disabled, the rest of this section is not displayed in
perfdump.
In the Admin
Console, the page displays zeros.
Tuning
By default, the DNS cache is on. You can enable or disable DNS caching in the Admin Console
on the configuration's Performance tab
⇒
DNS sub tab, under DNS Cache Settings and
selecting or deselecting the DNS Cache Enabled box. To enable or disable it using the
command-line-interface, use
wadm set-dns-cache-prop
and set the
enabled
property.
Cache Entries (Current Cache Entries / Maximum Cache Entries)
This section in
perfdump
shows the number of current cache entries and the maximum number
of cache entries. In the Admin Console the current cache entries are shown as Total Cache Hits.
A single cache entry represents a single IP address or DNS name lookup. The cache should be as
large as the maximum number of clients that access your web site concurrently. Note that
setting the cache size too high wastes memory and degrades performance.
Using Monitoring Data to Tune Your Server
Chapter 2 • Tuning Sun Java System Web Server 69