Can I use direct memory pool for ByteString

[coffee-core]

Is there way to hook up a callback from grpc after each message is sent done? Or it could be after the data is serialized to a different memory space.
I am trying to use Netty's DirectByteBuf for Created ByteString(use UnsafeByteOperations#unsafeWrap(ByteBuffer)） in the msg object and want to release those for reuse after the transmission is done.
Also, I'm wondering if it's possible to achieve zero-copy when sending messages if I do this.

[ejona86]

There's a way to do this for receiving, but nothing for sending.

There's been plenty of conversation around this, but it isn't a simple issue. Take a look at #1054, maybe starting somewhere near #1054 (comment) . I honestly don't remember how unclear an approach is for sending.

[ejona86]

Closing as a duplicate of #1054.