This pool was previously a pool.Bytes to avoid repetitive allocations.
It was recently switchted to a sync.Pool because pool.Bytes held onto
very larger buffers at times which were never released. sync.Pool is
showing up in allocation profiles quite frequently.
This switches the pool to a new pool that limits how many buffers are
in the pool as well as the max size of each buffer in the pool. This
provides better bounds on allocations.
This adds a new pool type that allows byte slices
to be re-used across clients. A sync.Pool can't be used in some
cases because the the slices not in use end up getting garbage
collected due to frequent GCs.
Jason Wilder
Mark Rushakoff