[test] periodic failure in import_export sparse image test
#2 Updated by Jason Dillaman about 1 year ago
It appears that the new "access timestamp" logic exposes an existing race condition in the rbd CLI export action. Previously, all librbd callbacks were serialized since only a single thread could invoke the callback (the cache finisher thread or the librados AIO finisher thread if the cache was disabled). Now, if the access timestamp needs to be updated, it's possible for concurrent callbacks to the rbd CLI export logic so the seek operations stomp on one another.