Хозяйке на заметку:
On Dell R900 with CentOS 5.2 and ext3 filesystem we get 1060 transactions/sec with single thread and sync_binlog=1 while with 2 threads it drops to 610 transactions/sec Because of synchronous serialized writes to binlog we're not expecting significant improvements in transaction rate (as the load is binlog fsync bound) but we surely do not expect it to drop ether.
To ensure this is not RAID controller related we repeated the run on the in memory block device and got very similar results - 2350 transactions/sec with 2 threads with sync-binlog=0 and just 750 transactions/sec with sync-binlog=1
We tried running data=writeback and data=journal just to make sure but results were basically the same.
Using XFS instead of EXT3 gives expected results - we get 2350 transactions/sec with sync_binlog=1 and 2550 transactions/sec with sync-binlog=0 which is about 10% overhead. [
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Такие вот, с позволения сказать, expected results.
А, вообще, используйте хорошие СУБД и не используйте плохие.