Question about fast path and slow path

Vikram Aroskar Vikram.Aroskar at Sun.COM
Mon Feb 23 19:33:44 PST 2009


I can try to answer #2 partially.

Fast path is basically lock free allocation.
This is mostly related to TLAB allocation where the allocating thread 
(is allocating in large contiguous free memory) need not worry about 
synchronisation. It can just allocate by incrementing the pointer.
Slow path is mainly synchronised allocation.
This mostly happens in the old generation, for eg in cases like a large 
object being allocated directly in the Old gen due to lack of space in 
the young gen.


On 02/24/09 02:25, Colin(Du Li) wrote:
> Hello,
> I have some questions about jvm slow path to ask you:
> 1. How can we force jvm to go slow path? Is there any jvm options?
> 2. What's the difference between slow path and fast path?
> 3. During slow path, will the interpreter translate the bytecode into
> assembly codes?
> Thanks a lot!
> Colin

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