Dan Stromberg <drsali...@gmail.com>: > BTW, there isn't much else going on on this computer, except some > possible small cronjobs.
The OS caches the files in RAM. You'd expect the file I/O performance to get much better on test reruns. On the other hand, OS cache flushing happens at random times, which affects the results in the other direction. Also, I take it you aren't running your tests in a virtual machine or on the cloud, right? Finally, you should run each test case in isolation. IOW, restart Python between each test case so the test cases don't interfere with each other. The startup overhead could be reduced by starting the test cases with an os.fork(). However, the performance tests should run long enough to overwhelm to startup and teardown overhead. Marko -- https://mail.python.org/mailman/listinfo/python-list