[#2577] ChannelOutboundBuffer.addFlush() unnecessary loop through all entries on multiple calls

Motivation:

If ChannelOutboundBuffer.addFlush() is called multiple times and flushed != unflushed it will still loop through all entries that are not flushed yet even if it is not needed anymore as these were marked uncancellable before.

Modifications:

Check if new messages were added since addFlush() was called and only if this was the case loop through all entries and try to mark the uncancellable.

Result:

Less overhead when ChannelOuboundBuffer.addFlush() is called multiple times without new messages been added.
This commit is contained in:
Norman Maurer 2014-06-17 09:26:04 +02:00
parent 9a169f5865
commit fe91aea655

View File

@ -182,18 +182,24 @@ public class ChannelOutboundBuffer {
* Mark all messages in this {@link ChannelOutboundBuffer} as flushed.
*/
public final void addFlush() {
unflushed = tail;
// There is no need to process all entries if there was already a flush before and no new messages
// where added in the meantime.
//
// See https://github.com/netty/netty/issues/2577
if (unflushed != tail) {
unflushed = tail;
final int mask = buffer.length - 1;
int i = flushed;
while (i != unflushed && buffer[i].msg != null) {
Entry entry = buffer[i];
if (!entry.promise.setUncancellable()) {
// Was cancelled so make sure we free up memory and notify about the freed bytes
int pending = entry.cancel();
decrementPendingOutboundBytes(pending);
final int mask = buffer.length - 1;
int i = flushed;
while (i != unflushed && buffer[i].msg != null) {
Entry entry = buffer[i];
if (!entry.promise.setUncancellable()) {
// Was cancelled so make sure we free up memory and notify about the freed bytes
int pending = entry.cancel();
decrementPendingOutboundBytes(pending);
}
i = i + 1 & mask;
}
i = i + 1 & mask;
}
}