2009/8/28 Schwab,Wilhelm K <[email protected]>:
> Sig,
>
> I must disagree, because there is more to what I am saying than simply to 
> skip cleanup (I am saying to do it in two parts, each at the correct time and 
> only at the correct time).  Further, the current behavior has nothing to do 
> with shutdown - it is done pre and post snapshot.  Dolphin has it right; we 
> should borrow the idea.
>

Oh, yes, i mistaken. I by shutdown i meant snapshot.
Its just from current Squeak POV shutdown is always performed before snapshot.


> Bill
>
>
> -----Original Message-----
> From: [email protected] 
> [mailto:[email protected]] On Behalf Of Igor 
> Stasenko
> Sent: Thursday, August 27, 2009 8:26 PM
> To: [email protected]
> Subject: Re: [Pharo-project] Startup/shutdown
>
> As a compromise, i suggest to introduce 2 different shutdown modes:
>  - with cleanup
>  - without cleanup
>
> and then reflect it in UI, or
> in system preferences.
> Case closed :)
>
> 2009/8/28 Schwab,Wilhelm K <[email protected]>:
>> I am not so sure it will not be a big deal.  With an open system, there is 
>> no reason not to use development tools to make changes on production 
>> machines, and saving the image would be part of that process; every 
>> occurance would clobber all sockets, all web users, all database 
>> connections, etc.  It's something that just feels wrong in capital letters, 
>> and we are trying to fix things.
>>
>> It definitely smells bad from a scientific computation perspective where 
>> external connections and saving the image are very common.
>>
>> Bill
>>
>>
>>
>> -----Original Message-----
>> From: [email protected]
>> [mailto:[email protected]] On Behalf Of
>> Miguel Enrique Cobá Martinez
>> Sent: Thursday, August 27, 2009 7:57 PM
>> To: [email protected]
>> Subject: Re: [Pharo-project] Startup/shutdown
>>
>> El jue, 27-08-2009 a las 20:23 -0400, Schwab,Wilhelm K escribió:
>>> Hello all,
>>>
>>> I am doing some more porting and hitting some trouble spots - no real 
>>> surprise that they exist.  However, I am struck by a strong belief that 
>>> Dolphin has a lot of things right, and startup and shutdown is very high on 
>>> that list.
>>>
>>> No offense to Nicolas, who has been quite helpful, let's consider a 
>>> somewhat extrmeme example.  Suppose a server is using an ORB to do SSL 
>>> protected communications with various servers and clients, some Seaside 
>>> work, and has a few database connections open.  Are we content with having 
>>> to close and reopen all of that just to save the image?  I submit that this 
>>> is a flawed design.  Worst case, the vm knows when it loads an image and 
>>> could tell the image that it happened.  From there, a lot of extra work 
>>> could be dumped.
>>>
>>> Nicolas is quite right that step (2) below must be done carefully, but it 
>>> has been handled nicely in Dolphin by registering potential offenders in 
>>> the startup triggers and doing the cleanup at that time.  External 
>>> resources are released on a shutdown trigger, but not image save.  This 
>>> will strike again with native windows, as the current approach would (stop 
>>> me if this is a fallacy) have everything released and reopened on image 
>>> save, which would be very inefficient.
>>>
>>> I have code that expects a class called SessionManager, and I am seriously 
>>> thinking of creating it.  It would trigger events for starup and shutdown, 
>>> help with logging, etc.  Can it be donw without hacking the vm?
>>>
>>
>> Just a question, what is the big deal with this, as you most often save on a 
>> development environment and not in a production environment. And as the 
>> number of saves on a production environment are seldom, it isn't a problem I 
>> think.
>> In the dev enviroment you are pointing to dev services and you have few open 
>> conections/whatever so that is not a big deal either.
>>
>>
>>> Bill
>>>
>>>
>>>
>>> ===========================================================
>>>
>>> [Pharo-project] Save and quit vs. Save - a clue to performance???
>>> Nicolas Cellier nicolas.cellier.aka.nice at gmail.com Thu Jul 16
>>> 22:48:34 CEST 2009
>>>
>>>     * Previous message: [Pharo-project] Save and quit vs. Save - a clue to 
>>> performance???
>>>     * Next message: [Pharo-project] Save and quit vs. Save - a clue to 
>>> performance???
>>>     * Messages sorted by: [ date ] [ thread ] [ subject ] [ author ]
>>>
>>> Current policy is to cleanup before saving, and reconnect after
>>> saving as if a fresh startup occured As you seem to suggest, a
>>> possible alternative without using fork would be to:
>>> 1) distinguish whether this is a newly restarted image (primSnapshot
>>> returning true or false...)
>>> 2) perform all the clean-ups at startup if newly restarted image
>>> 3) rely on the process exit() to perform required resource clean-up
>>> in case we quit (or let a self aboutToQuit do some)
>>>
>>> Step 2) would deserve great care, any unprotected access to an
>>> uninitialized pointer of the old image would crash or trash memory...
>>>
>>> Nicolas
>>>
>>> 2009/7/16 Schwab,Wilhelm K <bschwab at anest.ufl.edu>:
>>> > Nicolas,
>>> >
>>> > One thing I forgot to mention: thread safety???  IIRC, Dolphin triggers 
>>> > startup events, and all external resources clear pointers then (though 
>>> > they will release on shutdown, not image saving) to force a lazy 
>>> > connection.
>>> >
>>> > I see why, absent help from the vm, the image does not know when it 
>>> > starts and stops.  What I do not get is why the vm does not tell it.  If 
>>> > it did, I _think_ we could clean all of this up.  Sometimes the truth 
>>> > hurts though, so please find any faults in my logic (or lack thereof).
>>> >
>>> > Bill
>>>
>>>
>>> _______________________________________________
>>> Pharo-project mailing list
>>> [email protected]
>>> http://lists.gforge.inria.fr/cgi-bin/mailman/listinfo/pharo-project
>> --
>> Miguel Cobá
>> http://miguel.leugim.com.mx
>>
>>
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>
>
>
> --
> Best regards,
> Igor Stasenko AKA sig.
>
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-- 
Best regards,
Igor Stasenko AKA sig.

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