I am testing out Microsoft Azure Database for MySQL and have run into a performance issue that I do not understand.
I launched a "Basic" server with 1 vCore (2 GB RAM, "Standard Storage"), which is their lowest possible tier of server. I created a database, a table, and imported about 4 million rows (30 GB) with LOAD DATA INFILE. It took 56 minutes.
Next, I launched a "Memory Optimized" server with 8 vCores (80 GB RAM, "Premium Storage"). I repeated the exact same tasks and loaded the exact same file. This time it took 7 hours and 16 minutes.
Better server, much worse performance (on this task) -- not what I was expecting. To be certain I had not made a mistake, I repeated the steps above, but I got almost the exact same results again.
I suspect the issue is that the Memory Optimized server has different default server parameters than the Basic server which make this task perform more slowly (I haven't changed the parameters from the defaults that Azure sets). But I am not sure which parameters are the culprit. If anyone has insight into this issue, I'd appreciate it.
Basic server parameters: http://pastebin.zone/wRniyPm6
Memory Optimized server parameters: http://pastebin.zone/phuDcZj4