Projects/Replay cache improvements
Existing race condition when creating (or replacing on corruption). [krbdev.mit.edu #3498]
Possible file corruption due to lack of locking and not using O_APPEND [krbdev.mit.edu #1671]. Probable mechanism is two processes nearly simultaneously writing at the same file offset, which will cause overlapping writes unless O_APPEND is set.
Use of fsync() can cause performance problems. [krbdev.mit.edu #372]