[GitHub] eolivelli commented on a change in pull request #1572: Use readExplicitLAC instead of readEntry in order to get current LastAddConfirmed

[GitBox <gi...@apache.org>]

eolivelli commented on a change in pull request #1572: Use readExplicitLAC instead of readEntry in order to get current LastAddConfirmed
URL: https://github.com/apache/bookkeeper/pull/1572#discussion_r245975792
 
 

 ##########
 File path: bookkeeper-server/src/main/java/org/apache/bookkeeper/client/LedgerHandle.java
 ##########
 @@ -1335,6 +1335,14 @@ synchronized void updateLastConfirmed(long lac, long len) {
      */
 
     public void asyncReadLastConfirmed(final ReadLastConfirmedCallback cb, final Object ctx) {
+        if (clientCtx.getConf().useExplicitLacForReads) {
 
 Review comment:
   @sijie so you are suggesting to fallback to piggybackLac in case of "UnupportedOperation" error from bookie.
   We should keep track of this per-bookie. I think this is very tricky, we need to add a lot of code and runtime overhead for the sake of compatibility with very old bookies (4.4).
   
   We can have this configuration flag, enabled by default in 4.9 in case of v3+ protocol and disable for v2 protocol, and then drop it as soon as we decide to drop support for compatibility with such old versions.

----------------------------------------------------------------
This is an automated message from the Apache Git Service.
To respond to the message, please log on GitHub and use the
URL above to go to the specific comment.
 
For queries about this service, please contact Infrastructure at:
users@infra.apache.org


With regards,
Apache Git Services