| Date | Fri, 19 Sep 2008 14:42:58 -0700 | From | Randy Dunlap <> | Subject | Re: Unified tracing buffer |
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On Fri, 19 Sep 2008 14:33:42 -0700 Martin Bligh wrote:
> STORAGE > ------- > > We will support multiple buffers for different tracing systems, with > separate names, event id spaces. > Event ids are 16 bit, dynamically allocated.
What are these (like)?
> A "one line of text" print function will be provided for each event, > or use the default (probably hex printf) > Will provide a "flight data recorder" mode, and a "spool to disk" mode. > > Circular buffer per cpu, protected by per-cpu spinlock_irq > Word aligned records.
Arch-specific "word"? or some fixed-size-for-all-systems (so that trace buffers can be shared/used on other systems?) Preferably the latter.
> Variable record length, header will start with length record. > Timestamps in fixed timebase, monotonically increasing (across all CPUs)
what timestamp resolution?
--- ~Randy
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