I'm not saying it's impossible, but I'm not being successful at improving the performance on the UTF. I could save probably 1% of the time by writing directly on the OutputBuffer, with the introduction of ThreadLocals to reuse buffers on the string compressions. (Something that is probably being done at the JDK) (read it as complexity). So.. I don't think it's worth the effort. Think on the UTF as a compressed string: Characters between 1 and 0x7f will use 1 byte on the stream, characters > 0x800 will use 2 and anything between 0x7f and 0x799 will use 3 bytes on the streaming. BTW: the putString was very fast if not using the dynamicBuffer, making putStringNewWay moot. As Tim told me that we are changing this to use RegularBuffers, I'm not changing that. View the original post : http://www.jboss.org/index.html?module=bb&op=viewtopic&p=4211932#... Reply to the post : http://www.jboss.org/index.html?module=bb&op=posting&mode=reply&a...