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From: Steve Simon <steve@quintile.net>
To: tuhs@tuhs.org
Subject: [TUHS] kernel debugging in analogue
Date: Sat, 2 Jul 2022 00:38:11 +0100	[thread overview]
Message-ID: <D50BAA95-98D3-435A-B9D4-F11E5B0C9F88@quintile.net> (raw)


i remember a fellow student debugging an lsi11 kernel using a form of analogue vectorscope.

i think it had a pair of DACs attached to the upper bits of the address bus. it generated a 2d pattern which you could recognise as particular code - interrupts are here, userspace is there, etc.

the brightness of the spot indicated the time spent, so you got a bit of profiling too - and deadlocks became obvious.

anyone remember these, what where they called? i think it was an HP or Tek product.

-Steve


             reply	other threads:[~2022-07-01 23:41 UTC|newest]

Thread overview: 6+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2022-07-01 23:38 Steve Simon [this message]
2022-07-02  1:52 ` [TUHS] " Al Kossow
2022-07-02  1:57   ` Al Kossow
2022-07-02  2:45   ` Grant Taylor via TUHS
2022-07-02  2:50     ` Al Kossow
2022-07-02  6:20       ` Grant Taylor via TUHS

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