path: root/extras
diff options
authorAnand Avati <>2012-09-13 22:26:59 -0700
committerAnand Avati <>2012-10-01 12:45:18 -0700
commitc903de38da917239fe905fc6efa1f413d120fc04 (patch)
tree6387677f13c700305e704dad7d274f656526287b /extras
parentdd8eb06e26138e149252365043706067782416af (diff)
write-behind: implement causal ordering and other cleanup
Rules of causal ordering implemented: - If request A arrives after the acknowledgement (to the app, i.e, STACK_UNWIND) of another request B, then request B is said to have 'caused' request A. - (corollary) Two requests, which at any point of time, are unacknowledged simultaneously in the system can never 'cause' each other (wb_inode->gen is based on this) - If request A is caused by request B, AND request A's region has an overlap with request B's region, then then the fulfillment of request A is guaranteed to happen after the fulfillment of B. - FD of origin is not considered for the determination of causal ordering. - Append operation's region is considered the whole file. Other cleanup: - wb_file_t not required any more. - wb_local_t not required any more. - O_RDONLY fd's operations now go through the queue to make sure writes in the requested region get fulfilled before getting processed. - O_SYNC fd's operations now go through the queue to make sure previously acknowledged writes on the file (via other fds) are fulfilled before getting processed. - Option to not honor O_SYNC is now removed. - Option to ignore O_DIRECT is added (useful when running a VM and the drive appears with NCQ/TCQ or WCE=1 for the guest.) - Option to disable_first_nbytes is removed (as the cause of the bug which required this was diagnosed to be missing TCP_NODELAY.) - General cleanup and better conformance to coding style and convention. Change-Id: Ib44fb72da3727246b4a85174cb568c2f0231f6de BUG: 857673 Signed-off-by: Anand Avati <> Reviewed-on: Tested-by: Gluster Build System <> Reviewed-by: Jeff Darcy <> Reviewed-by: Amar Tumballi <>
Diffstat (limited to 'extras')
0 files changed, 0 insertions, 0 deletions