Re: InetAddress should utilize networkaddress.cache.ttl for getLocalHost() too

[Michael McMahon]

On 24/07/12 07:17, Deven You wrote:

Hi Alan and Michael,

I add a java doc[1] for the new networkaddress.cache.localhost.ttl 
property. Please take a look when you have time.




The change looks fine to me. There is a typo in the apidoc in InetAddress.
"as as" should be "as an". Might as well correct the same mistake in the 
previous

paragraph also.

Since this is a spec change, it will need a CCC request. Is there a bug 
id for this issue?
Again, I don't know how to set 
cachePolicyPropFallback/negativeCachePolicyPropFallback. Any 
suggestion please tell me.




These are system properties. So, they are normally set on the command 
line with java -Dsun.net.inetaddr.ttl=X 


- Michael.

[1] http://cr.openjdk.java.net/~youdwei/ojdk-527/webrev.01/ 


Thanks a lot!

On 07/12/2012 02:59 PM, Deven You wrote:

Hi Alan and Michael,

Thanks very much for your kind suggestions.

I agree that local host shouldn't follow the default caching 
mechanism because the IP may change frequently. And I also think 
making the cache time configurable is a better solution.


I am willing to make these changes including adding the local host 
caching mechanism into the java doc.


I have gone through the related code for InetAddress.java and 
InetAddressCachePolicy.java. And I think we could add a new security 
property networkaddress.cache.localhost.ttl to achieve the goal.


As far as I know, to add networkaddress.cache.localhost.ttl I need 
change jdk/src/share/lib/security/java.security*(include 
java.security, java.security-solaris, java.security-macosx and 
java.security-windows). Please correct me if I have any misunderstanding.


Here I have one question need your help:
the static block in InetAddressCachePolicy.java will first try to 
get cachePolicyProp/negativeCachePolicyProp from System properties. 
If one of the cache values is null then the value of 
cachePolicyPropFallback/negativeCachePolicyProp would be got from 
System properties.
   I don't know where we declare these fallback properties so I have 
no idea where I can do the same thing for 
networkaddress.cache.localhost.ttl.


Please take a look.

Thanks a lot!


On 07/11/2012 06:55 PM, Michael McMahon wrote:

On 11/07/12 08:00, Alan Bateman wrote:

On 05/07/2012 07:10, Deven You wrote:

Hi All,

I noticed that InetAddress.getLocalHost() uses cache to improve 
the performance. However the default implementation is caching 
local host within 5 seconds.


From the spec, networkaddress.cache.ttl should be used to control 
the cache behaviour and I think it is a better solution.


For example, if the networkaddress.cache.ttl is set to -1 which 
means always cache the local host then we can avoid unnecessary 
operations on getAddressesFromNameService to improve the performance.


I have made a patch for this solution, so anyone would like to 
take a look?


[1] http://cr.openjdk.java.net/~littlee/OJDK-527/webrev.00/ 


Thanks a lot!
--
Best Regards,

Deven
I'm not sure about this one as I suspect it will cause problems in 
DHCP or any environments where the host addresses changes, say 
moving to a different wireless network or waking up a machine after 
hibernation.


-Alan


That's true. We updated the spec for the caching behavior a while 
back, and probably should have included this exception
for the local host. I agree that we shouldn't change the behavior. 
Perhaps, the 5 seconds could be configurable itself,

but I think it should be kept separate from the main caching behavior.

- Michael.




--
Best Regards,

Deven



--
Best Regards,

Deven

hg: jdk8/tl/jdk: 7186829: test/sun/nio/cs/OLD/JIS_X_0201_OLD.java failed in jdk8 TL nightly build

[xueming . shen]

Changeset: 42eac77355d2
Author:sherman
Date:  2012-07-25 12:47 -0700
URL:   http://hg.openjdk.java.net/jdk8/tl/jdk/rev/42eac77355d2

7186829: test/sun/nio/cs/OLD/JIS_X_0201_OLD.java failed in jdk8 TL nightly build
Summary: fixed the test case
Reviewed-by: alanb

! test/sun/nio/cs/OLD/JIS_X_0201_OLD.java