I sent a message out a while back:
>
> In the past when I have used the stop <variable> command in dbx or
> decladebug, the performance is very slow due to implementing the watch
> point via single stepping. The fast "set watch" command implemented
> in VMS debug and some debuggers available on other Unix
> implementations, can nail done bugs in no time. Are there any
> debuggers available on DEC Unix that have a fast watch point feature?
> If not, has anyone heard a rational from DEC on why they have not
> implemented one?
>
> I'll post a summary to the responses I receive.
>
> Thanks,
>
> Doug Gilmore
> AIG Financial Products.
To which I got two replies:
From: "Steven W. Orr" <steveo_at_uniprise.com>
Subject: Re: Though this might interest you
In-reply-to: <9511031620.AA22535_at_calvin>
X-Sender: steveo_at_thor.dev.uniprise.com
To: "Jim Johnson - UniPrise Systems - 617.229.1105" <jj_at_uniprise.com>
Cc: GILMORE_at_aigfpc.com
Message-id: <Pine.OSF.3.91.951103112533.7678A-100000_at_thor.dev.uniprise.com>
...
Vaxen and 80[3456]86 processors have a set of registers that can be set
to implement watchpointing in hardware. I don't know (I think they don't)
if Alpha's have such support. Without it, you're SOOL.
However, I have heard that execution while a watch point is set in DEBUG running
on Alpha VMS is significantly faster than when "stop if (expr)" is specified
under dbx, though I have not been able to verify this.
Also:
From: Mike Palmer <mpalmer_at_encore.com>
Subject: Re: Fast watch points in DEC Unix debuggers?
...
Encore Computer Corporation has a debugging and program analysis product called
Parasight that can be used on real-time (or dynamic) applications without
stopping them.
It allows you to monitor the data (global or local) in any program while it is
running. Global data monitoring is totally non-intrusive. Local monitoring
is minimally intrusive.
Parasight also allows dynamic program execution analysis, permitting on the fly
placement of instrumentation points throughout your programs - again while they
are running - and you can see the results of the instrumentation immediately -
in graphical from - and again without stopping the programs being instrumented.
You can find out more about Parasight on our www page:
http://www.encore.com
and can even download a demo version of Parasight from:
ftp.encore.comi/pub/development/demos/alpha
Please let me know if you have any difficulty obtaining or running the demo copy.
Thanks for the help!
Doug Gilmore
AIG Financial Products
Received on Tue Nov 21 1995 - 00:41:13 NZDT