Messages in this thread | | | Date | Sun, 18 Nov 2007 22:34:27 +0100 | From | Sam Ravnborg <> | Subject | Re: [PATCH] Time-based RFC 4122 UUID generator |
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On Sun, Nov 18, 2007 at 01:05:03PM -0800, Andrew Morton wrote: > On Sun, 18 Nov 2007 20:38:21 +0100 Helge Deller <deller@gmx.de> wrote: > > > Title: Add time-based RFC 4122 UUID generator > > > > The current Linux kernel currently contains the generate_random_uuid() > > function, which creates - based on RFC 4122 - truly random UUIDs and > > provides them to userspace through /proc/sys/kernel/random/boot_id and > > /proc/sys/kernel/random/uuid. > > > > This patch additionally adds the "Time-based UUID" variant of RFC 4122, > > with which userspace applications can easily get real unique time-based > > UUIDs through /proc/sys/kernel/random/uuid_time. > > A new /proc/sys/kernel/random/uuid_time_clockseq sysfs entry is available, > > so that the clock_seq value can be retained across system bootups (which > > is required by RFC 4122). > > > > The attached implementation uses getnstimeofday() to get very fine-grained > > granularity. This helps, so that userspace tools can get a lot more UUIDs > > (if needed) per time than before. > > A mutex takes care of the proper locking against a mistaken double creation > > of UUIDs for simultanious running processes. > > Who will use this feature, and for what? > > (In fact, who uses the existing UUID generators, and for what?)
I use libuuid and I assume libuuid uses some uuid generator support from the kernel. libuuid comes from a package that Ted's maintain IIRC.
I (my company) use uuid to uniquely identify objects in a distributed database. [Proprietary closed source stuff].
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