Hi everybody, here are some first results from my benchmarks of replication / group commit performance. The benchmark is sysbench OLTP rw, data set fitting in memory. I tested a total of 27 configurations, 9 each for Maria-5.5.36, Maria-10.0.9 and MySQL-5.6.16. Variations were for binlog on/off, SBR vs. RBR and sync_binlog=0/1. For MariaDB I also tested XtraDB vs. InnoDB, for MySQL it was GTID on vs. GTID off. Not surprisingly turning on the binlog comes with a performance penalty. Also sync_binlog=1 adds another penalty. Quite consistently RBR was a little bit slower than SBR for all combinations (I also observed the binlogs to be bigger for RBR by a factor of nearly 2). The only real surprise was the cost of GTID in MySQL as can be seen in the attached plot. MariaDB-10.0 has GTID enabled by default (you cannot even turn it off) Right now the same benchmark is running again, this time using a single disk for binlogs (was a fast RAID before). Next step is applying binlogs to a slave with different settings for number of slave threads etc. XL
