By Henk Vandenbergh on Jul 15, 2011
After elapsed=nn seconds, Vdbench tells its slaves to terminate the current run, and waits for them to do so. If that takes more than 30 seconds Vdbench displays this message: "SlaveList.waitForSlaveWorkCompletion()".
Why could it take more than 30 seconds? At the end of a run no new i/o is generated by Vdbench, but it still has to wait for i/o that is already outstanding to complete. But why can that take more than 30 seconds? There can be multiple reasons for that.
- One reason can be that the storage device is dead or dying, something I hope you won't see out there in the real user world.
- An other reason is that we specified such a huge amount of Vdbench thread count that the amount of i/o outstanding at run termination time is so overwhelming that indeed it can't finish within 30 seconds.
- One more reason: you are running against a file system (or a cached volume, e.g. /dev/dsk instead of /dev/rdsk) and flushing all the remaining dirty blocks from cache takes very long.