RFR (M) 8061651 - Interface to the Lookup Index Cache to improve URLClassPath search time
ioi.lam at oracle.com
Tue Oct 21 17:27:20 UTC 2014
Please review this fix:
Bug: Add an interface to the JVM's Class/Resource Lookup Index Cache for
improving sun.misc.URLClassPath search time
Summary of fix:
Some J2EE environments have lots of JAR files in the
classpath. However, during run-time, most classes are loaded by
custom classloaders which delegate to the system loader. As a
result, each class loaded by a custom classloader will cause many
JAR search failures (in sun.misc.URLClassPath).
To limit the number of searches in URLClassPath, the 8uX HotSpot
VM is going to include a Class/Resource Lookup Index Cache that
records information about the class/resource entries in the JAR
files in the classpath. This can be used to improve
sun.misc.URLClassPath search time.
This is part 1 of the REF -- we are adding appropriate interfaces
in both the JDK code and the HotSpot code to access this cache.
URLClassPath.java is modified to use JNI to call into the HotSpot
JVM_XXX APIs to access the cache.
The implementation of this cache is done in part 2 of this RFE.
Note that this enhancement is for JDK 8uX only. In JDK9 and
beyond, we are considering an alternative implementation where the
cache is maintained in the core libs code, outside of HotSpot.
Adhoc SQE tests
More information about the core-libs-dev