Messages in this thread | | | Date | Tue, 23 Sep 2008 23:36:26 +0900 (JST) | From | KOSAKI Motohiro <> | Subject | Re: Unified tracing buffer |
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> By the way, systemtap uses two modes; > > - single-channel mode > In this mode, all cpus share one buffer channel to write and read. > each writer locks spinlock and write a probe-local data to buffer. > > - per-cpu buffer mode > In this mode, we use an atomic sequential number for ordering data. If > user doesn't need it(because they have their own timestamps), they can > choose not to use that seq-number.
I can't imazine a merit of the single-channel mode. Could you please explain it?
Because some architecture don't have fine grained timestamp? if so, could you explain which architecture don't have it?
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