… no effect on standard MySQL replication from this instance, since MySQL replication is asynchronous. What about semi-sync MySQL replication? It’s actually much worse than Galera. As I illustrated in a blog post last year, semi-sync… time. So, Callaghan’s law applied to semi-sync is: [On a semi-sync replication master] you can’t commit (at all) more…
Comment: Is Synchronous Replication right for your app?
May 14, 2013 By 18 Comments
… this level of detail. I have not reviewed or tested semi-sync in official MySQL so I am surprised by this… occurs. But my peers are interested in semi-sync now so we will verify this. “Semi-sync performs dismally under concurrency. Think…, so we are effectively serializing our 32 clients with semi-sync replication. Apparently each client must wait for it’s turn writing…
Post: How Does Semisynchronous MySQL Replication Work?
January 19, 2012 By 24 Comments
… about MySQL’s semi-synchronous replication. I find that there are often a number of misconceptions about how semi-synchronous replication really works. I think it is very important to understand what guarantees you actually get with semi-synchronous replication, and…, that is not what happens in semi-synchronous replication. And if there is an error in semi-synchronous replication, such as a crash at…
Post: Comparing Percona XtraDB Cluster with Semi-Sync replication Cross-WAN
June 14, 2012 By 7 Comments
… wanted me to do a test comparing PXC against semi-synchronous replication to see how they stack up against each other. Test… ~100ms, so we are effectively serializing our 32 clients with semi-sync replication. Apparently each client must wait for it’s turn… way to parallelize semi-synchronous replication (at least in 5.5), I could be missing something. PXC’s true parallel replication shines here…
Post: Automation: A case for synchronous replication
September 19, 2012 By 2 Comments
… end up with inconsistent database, broken replication and other problems. I should note semi-synchronous replication available in MySQL 5.5 does not… as semi synchronous replication does not wait for execution only for queing event in relay log. Now lets see how Synchronous Replication solutions…
Post: Benchmarking Galera replication overhead
October 13, 2011 By 12 Comments
… in Galera cluster replication – result using 2 nodes under regular MySQL replication semisync – result using 2 nodes with semisync MySQL replication And now… Galera replication this is NOT a problem. 4. Now it is interesting how Semi-Sync replication will do under this workload. For Semi-Sync replication…
Post: Debugging problems with row based replication
May 6, 2010 By 12 Comments
… like RAND() are used in DML statements. A statement based replication slave can get out of sync with the master fairly… row-based logs only contain information about changed rows, a replication slave which does not find a row referenced in a… base64 output and instead replaces the output with semi-valid SQL statements. I say semi-valid because the statements do not include…
Post: How does MySQL Replication really work?
January 9, 2013 By 9 Comments
… blog posts on replication on our blog, such as on replication being single-threaded, on semi-synchronous replication or on estimating replication capacity, I don’t think we have one that covers the very basics of how MySQL replication…
Post: Ultimate MySQL variable and status reference list
January 8, 2011 By 4 Comments
…replicate_do_dbblogpercona.commanual replicate_do_tableblogpercona.commanual replicate_ignore_dbblogpercona.commanual replicate_ignore_tableblogpercona.commanual replicate_rewrite_dbblogpercona.commanual replicate_same_server_idblogpercona.commanual replicate…
Comment: How Does Semisynchronous MySQL Replication Work?
January 19, 2012 By 24 Comments
… Semi Synchronous replication was noted and there is a patch to improve it: http://code.google.com/p/enhanced-semi-sync-replication/ With Enhanced Semi Sync Replication…
