Can Amazon RDS Small do 200 timestamp updates on a primary key per second?

I'm trying to get an idea of how much load a SMALL RDS instance type can handle.

I know this is highly subjective, but given that开发者_运维百科 it's being done on a primary key and a timestamp field is being updated, the table has about 500,000 rows, will this be a problem? Assume this is the only table in the database.

If it will be a problem, what about for a large instance?

What's a reasonable estimate for how many such updates a small/large instance can handle?

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Short answer: Yes, easily.

Long answer:

• Mysql 5.5
• Innodb table with ~200k rows
• 128-bit natural primary key
• Datetime column not part of any key
• No other indexes
• Otherwise idle RDS m1.small instance
• 20x mysql commandlines in parallel doing UPDATE tbl SET date='$now' WHERE pk='$key' for different random-shuffled lists of existing primary keys

This pins the instance CPUs at 100% and mantains a steady update rate a little higher than 2000 updates per second. Write I/O ran at about 600 IOPS. Since it's CPU-bound if you're using prepared statements or batching your inserts I'm sure you can do much better before running out of CPU.