You can modify the size of the buffers to change how much diagnostics output is provided in a snap dump. This buffer is allocated for each thread that makes trace entries.
From Java™ 6 SR 5, you do not need to specify the buffer size.
If external trace is enabled, the number of buffers is doubled; that is, each thread allocates two or more buffers. The same buffer size is used for state and exception tracing, but, in this case, buffers are allocated globally. The default is 8 KB per thread.
The dynamic and nodynamic options have meaning only when tracing to an output file. If dynamic is specified, buffers are allocated as needed to match the rate of trace data generation to the output media. Conversely, if nodynamic is specified, a maximum of two buffers per thread is allocated. The default is dynamic. The dynamic option is effective only when you are tracing to an output file.
-Xtrace:buffers=2mor in a properties file:
buffers=2m
-Xtrace:buffers={128k,nodynamic}or in a properties file:
buffers=128k,nodynamic
-Xtrace:buffers=nodynamicor in a properties file:
buffers=nodynamic