On Wed, Nov 29, 2017 at 07:46:08PM -0600, Ashlie Martinez wrote: > > 5. Since I'm too lazy to wait 120 seconds, just force everything to disk: > > > > sync > > I believe you said in an earlier email that sync would erase any trace > of the bug Amir found as it resolves the delayed allocation. Right, but you're waiting 120 seconds, which is enough time that it would resolve the delayed allocation. So that's why I was trying to replicate your Crashmonkey experiment. And since you stated that you waited 120 seconds as the last step, there should have been a barrier, and no I/O operations for Crashmonkey to rearrange. This is why I believe what I listed should be exactly the same as your Crashmonkey test, if I understood it correctly. What you said was that you ran the following operations on the test file: 1. write 0x137dd 0xdc69 0x0 2. fallocate 0xb531 0xb5ad 0x21446 3. collapse_range 0x1c000 0x4000 0x21446 <sleep 30> 4. write 0x3e5ec 0x1a14 0x21446 5. zero_range 0x20fac 0x6d9c 0x40000 keep_size <sleep 120> So what was the block I/O trace? What operations was crashmonkey actually reordering? There **really** shouldn't have been any.... Can you send the block I/O trace that was observed when you did the following, a complete output of dumpe2fs on the file system, and a debugfs stat output on the test file? - Ted P.S. I did read the Crashmonkey paper, so I'm aware of what Crashmonkey does. I'm just confused about your workload, since the 120 second sleep should have meant there was a barrier followed by nothing else, making for a *very* boring crashmonkey replay.
