[doublebuffer] retain current capacity and reuse
[doublebuffer] retain current capacity and reuse

h2o/h2o,h2o/h2o,h2o/h2o,h2o/h2o,devnexen/h2o,devnexen/h2o,h2o/h2o,cwyang/h2o,devnexen/h2o,h2o/h2o,cwyang/h2o,yannick/h2o,devnexen/h2o,cwyang/h2o,devnexen/h2o,yannick/h2o,yannick/h2o,yannick/h2o,devnexen/h2o,yannick/h2o,devnexen/h2o,devnexen/h2o,cwyang/h2o,yannick/h2o,yannick/h2o,h2o/h2o,cwyang/h2o,cwyang/h2o,cwyang/h2o,devnexen/h2o,yannick/h2o,h2o/h2o,cwyang/h2o,yannick/h2o,h2o/h2o