1958 US–UK Mutual Defence Agreement as an atomic spy, caused the proposal to be dropped. The June 1951 defection of Donald Maclean, who had served as a British member of the Combined Policy Committee from January 1947 to August 1948, reinforced the Americans' distrust of British security arrangements. The first British atomic bomb was successfully tested in Operation Hurricane on 3 October 1952, but although it was more advanced than the American bombs of 1946, Britain was still several years behind in nuclear weapons technology. The United States conducted Ivy Mike, the first nuclear test of a true thermonuclear device (also known as a hydrogen
Journaling block device Journaling block device JBD, or journaling block device, is a generic block device journaling layer in the Linux kernel written by Stephen C. Tweedie from Red Hat. The Journaling Block Device (JBD) provides a filesystem-independent interface for filesystem journaling. ext3, ext4 and OCFS2 are known to use JBD. OCFS2 starting from Linux 2.6.28 and ext4 use a fork of JBD called "JBD2". An atomic handle is basically a collection of all the low-level changes that occur during a single high-level atomic update to the file system. The atomic handle guarantees that the high-level update either happens or not, because the