Viewing Memory Allocation Information

This panel displays information about how JRockit is allocating memory on the Java heap (Figure 6-7). A Thread Local Area (TLA) is a JRockit internal value. It is a small memory area, local to a thread, where the JVM can allocate small objects without having to take the heap lock. For an in-depth explanation of how TLA works, please see Setting the Thread Local Area Size in the BEA JRockit Diagnostics Guide. See also -XXtlaSize in the BEA JRockit Reference Manual for more information on how to set different values of the TLA size.

Preferred thread local area (TLA) size is the value that you have set with the command-line option -XXtlasize:preferred <size>.
Minimum thread local area size is the value that you have set with the command-line option -XXtlasize:min <size>.
Ratio of bytes for large/small objects. Per default, JRockit considers an object to be large if it is larger than the thread local area size; it is small if it would normally fit in a thread local area. Large objects are always allocated in the old space (second generation) of the heap, never in the nursery.
The Number (#) free list misses is a JRockit internal value. JRockit has a list of free memory blocks on the Java heap. During allocation, an object is normally put in the first free block on the "free list." If it does not fit there, JRockit will try the next block, and the next, etc. Each block where the code block did not fit is considered a "free list miss."

Figure 6-7 Allocation panel

Allocation panel