allow channel programs to be stopped via signals
ZFS Channel program scripts currently require a timeout, so that hung or long-running scripts return a timeout error instead of causing ZFS to get wedged. This limit can currently be set up to 100 million Lua instructions. Even with a limit in place, it would be desirable to have a sys admin (support engineer) be able to cancel a script that is taking a long time.
Make it possible to abort a channel program by sending an interrupt signal.In the underlying txg_wait_sync function, switch the cv_wait to a cv_wait_sig to catch the signal. Once a signal is encountered, the dsl_sync_task function can install a Lua hook that will get called before the Lua interpreter executes a new line of code. The dsl_sync_task can resume with a standard txg_wait_sync call and wait for the txg to complete. Meanwhile, the hook will abort the script and indicate that the channel program was canceled. The kernel returns a EINTR to indicate that the channel program run was canceled.
Updated by Electric Monk almost 3 years ago
- Status changed from New to Closed
- % Done changed from 0 to 100
commit d0cb1fb92629bc0283c88d4719df7285c1612700 Author: Don Brady <firstname.lastname@example.org> Date: 2019-02-20T18:05:08.000Z 9425 allow channel programs to be stopped via signals Reviewed by: Sebastien Roy <email@example.com> Reviewed by: Serapheim Dimitropoulos <firstname.lastname@example.org> Reviewed by: Matt Ahrens <email@example.com> Approved by: Robert Mustacchi <firstname.lastname@example.org>