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Bug ID: JDK-6903284 Data read from system cache should be also cached in the memory cache
JDK-6903284 : Data read from system cache should be also cached in the memory cache

Details
Type:
Bug
Submit Date:
2009-11-20
Status:
Closed
Updated Date:
2010-09-16
Project Name:
JDK
Resolved Date:
2010-01-13
Component:
deploy
OS:
generic
Sub-Component:
deployment_toolkit
CPU:
generic
Priority:
P2
Resolution:
Fixed
Affected Versions:
6u18
Fixed Versions:
6u18 (b06)

Related Reports
Backport:
Relates:

Sub Tasks

Description
Cache.getSystemCacheEntry() does not use memory cache and therefore cache entries from the system cache 
are always read from the disk (or disk cache). This has negative impact on performance.

                                    

Comments
EVALUATION

As part of FX startup optimizations in 6u18 FX runtime is now imported in the "system" cache and we use special optimized classloader to load runtime from the system cache.

In b05 (6894899) this code was refactored to make sure we only allow system cache entries to be loaded to the "optimized" FX classloader. However, this codepath skips use of MemoryCache and therefore every time we need jar (e.g. to load new class) we read cache entry from the disk (disk cache but we still need to load and parse it).

For example this happens 650 times on startup of Store app.

Other problem fixed as part of this bug fix is to recover support for use of "alternative"
runtimes - this is needed for performance tracking with Soma promoted builds.

Perf tests shows that with fix startup performance for minimal fx applet improves by 10+%  (this will likely return us to b04 level only).
                                     
2009-11-21
SUGGESTED FIX

http://sa.sfbay.sun.com/projects/deployment_data/6u18/6903284.1
                                     
2009-11-24
SUGGESTED FIX

http://javaweb.sfbay.sun.com/~in81039/6903284/
                                     
2009-11-21



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