[IGSTK-Developers] Crash recovery?

[Tina Kapur]

Thanks, David, Andy.

Like you said, David, systems crashes can be independent of the robustness
of the application software, and for whatever reason (stress photons?) they
happen frequently in the OR.  In my experience with various types of
surgeries/IGS systems, while a system crash is considered a
fact-of-life-that-leads-to-delay, a system unable to recover its state is a
bad thing.  For example,  typical neurosurgery IGS applications use
point-based registration that is performed at the start of the procedure,
before the patient is draped. If this system were to crash well after the
patient has been draped and the sterile field set up, without crash recovery
capability, the surgeon will have to abandon use of the system completely
for the rest of the case because even if they were willing to start over, at
this point in the surgery they can no longer access points/landmarks on the
patient's skin. This will make the surgeon less willing to put in the
upfront effort of doing the registration and generally using IGS the next
time.

And yes, logging specific information about all steps that are perfomed
(data loading, all registrations, image manipulation) would need to be
stored, if you were to do this.

Finally, if the goal is to have an application use IGSTK as one of it's
components, it makes sense to leave crash recovery to the individual
application writers.  However, if applications will be written using IGSTK
only, it might be worth planning this in.

-Tina

>-----Original Message-----
>From: David Gobbi [mailto:dgobbi at atamai.com] 
>Sent: Thursday, September 08, 2005 3:39 PM
>To: Tina Kapur
>Cc: 'IGSTK Developers'
>Subject: Re: [IGSTK-Developers] Crash recovery?
>
>Hi Tina,
>
>So far we've focused on crash avoidance, but crash recovery is 
>definitely a good thing too.  Crashes can't be completely 
>avoided (at least not on Windows or Linux, which are the 
>target operating systems).
>
>Right now the way that igstk object do their logging isn't 
>suitable for recovery, the loggers are being used to keep 
>track of method calls, state changes, etc.
>
>What we would need is to keep a log of specific information 
>that can be used for crash recovery, e.g. which data sets have 
>been loaded, what the result of most recent patient 
>registration was, etc. 
>
>There are no plans to support this in the current iteration, 
>but since the Reader and Registration classes have just been 
>added, it's probably worth considering how those classes can 
>log some info that can be use for recovery.
>
> - David
>
>
>Tina Kapur wrote:
>
>>Hi,
>>
>>Does IGSTK have a mechanism for crash recovery?  I was making a wish 
>>list of what such a toolkit should have, and I can see how 
>the logging 
>>mechanism could be used for recovery from a mid surgery 
>crash, but just 
>>wanted to check if the feature was planned for anytime in the 
>near future.
>>
>>Thanks.
>>-Tina
>>
>>
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>>
>
>
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