The following screenshots outline the amount of time taken to open the ./question/category.php page for three different server environments.
Unfortunately, I have nothing to test in this area.
I'm attaching a rough profiling of one of my servers setup specifically for moodle. Below are profiles of various pages.
|Execution time||CPU time||Function calls||Memory used|
|/index.php||1013.398 ms||920.057 ms||292836||20955.758 KB|
|/course/index.php||644.096 ms||628.038 ms||236747||17383.719 KB|
|/mod/scorm/view.php||720.829 ms||692.042 ms||258900||19396.406 KB|
|/course/view.php||952.654 ms||888.056 ms||325416||20690.656 KB|
|/pluginfile.php||17.841 ms||16.001 ms||4113||3003.828 KB|
|/index.php||1126.557 ms||984.062 ms||305764||21371.117 KB|
|/user/view.php||802.452 ms||780.048 ms||294178||19914.047 KB|
|/grade/report/grader/index.php||1939.602 ms||1884.118 ms||728265||26474.047 KB|
|/course/view.php||948.076 ms||880.055 ms||325239||20614.188 KB|
|/index.php||1133.060 ms||996.061 ms||305802||21386.063 KB|
Web Server: m2.2xlarge, 64-bit, 4 cores, 34.2GB RAM, 850GB storage
|High-Memory Double Extra Large||34.20 GB||13 (4 cores x 3.25 units)||850 GB||64-bit||High||120||m2.2xlarge||$590.40 monthly|
The overall cost compared to the performance is abysmal at best
Database Server: hi1.4xlarge, 64-bit, 16 cores, 60.5GB RAM, 2 x 1024GD SSD storage
|High I/O Quadruple Extra Large||60.50 GB||35 (8 cores + 8 hyperthreads)||2048 GB (2x1024 GB SSD)||64-bit||Very High||1||hi1.4xlarge||$2232.00 monthly|
Again, performance vs cost is abysmal.
Also, I had read a MYSQL performance tuning guide that stated that MYSQL performance would decrease for server with more than 8 cores. I have tested a number of instances and have not really noticed significant performance decreases for MYSQL queries on instances with more than 8 cores, but should I still be concerned about this?
I would not be concerned. You likely would never require more than eight cores in a single server. Anything over eight cores is ideal for setting up virtual servers, gaming servers, encoding, and other processor intensive tasks. You are far better off with two 4 core servers turned to handle their designated task. ex: one web server, one database server
I think a lot of people are confused about optimizing moodle. Depending how your system is setup an average user uses about 25mb of ram. Lets say 16gb of ram might handle 500 students. In reality the cpu and ram may be able to handle this, yes with load, but the file system will not come close.
Worth reading if your stuck with Amazon. Raid EBS
Quick hardward test (very basic) hdparm -t /dev/sda#
Timing buffered disk reads: 1572 MB in 3.00 seconds = 523.49 MB/sec server above
Timing buffered disk reads: 544 MB in 3.01 seconds = 180.85 MB/sec another dedicated server
I'm not sure what Amazon EC instances output but might be worth a quick check. You can also use sysbench or unixbench to perform basic tests across various hardware.
Anything else feel free to reply to the post or posts above!